Hi everyone, my name is Sean and this is my first post here so hello!
I do not own a bus (sorry), but I do own a commercial vehicle that I am converting to an RV.
I joined this board because countless Google searches pointed to this board as a place where many people have experience with the DD 6-71 motor that my rig is powered by, and also because I am doing a RV conversion (just not from a bus).
To start with, I would like to ask some questions that would have generic answers, but keep the spec's of my rig and it's purpose in mind also.
My "rig" is as such:
1983 Hendrickson / Calumet Coach
39' long
Tandem axle (with inter-axle lockout)
22.5" tires
Curb weight: 34,500lbs
Detroit Diesel 6-71 turbo (not inter or after cooled that i can tell) horizontally mounted near the center of the truck.
Allison 5 speed auto
Engine reported by seller to have been rebuilt in 2000 with around 145,000 current miles.
My experience with Diesel trucks is limited to owning:
1999 Dodge 3500 w Cummins
1990 International Crew hauler with DT466(T)
2000 Freightliner FL-60 with 3126 (300hp/980@12,000lbs)
Plus rentals and other people's diesel trucks I've driven over the years.
I mention these so you know where I'm at.
Now the reason I'm asking the question is because this rig is a dog. Even in the lowest powered diesel I've owned (the DT466), my driving skill allowed me to negotiate the highways. This vehicle seems so underpowered to me that I feel I need to find the problem, or if there isn't one, find a way to get at least another 20% out of the motor just to be safe.
I am not trying to "hot rod" the motor, or pass the semi's on the passes, and fuel economy matters to me, but there is a point where needing more power is a very mature thing to require.
Currently, the motor seems to run fine. This is my first two stroke, so "running fine" is just a guess, but it goes pretty smooth without much smoke unless you're flooring it going slow enough to see it.
It hunts at startup for about 20 seconds and calms down to a nice idle (although high at about 2k).
There doesn't seem to be anything obviously wrong with it (noises, vibrations, leaks..etc), but it just feels so underpowered that I can't imagine a truck manufacturer letting it go out the door like this.
It is currently getting about 7mpg avg, but mostly highway (calculated from the 800mi trip it took to get it home). This, again, is at 34,000lbs.
In the passes, I am by far the slowest thing on the road (well there was that cyclist I passed once). I have to fight even low percentage grades (1-2 even).
It's embarrassing and frustrating having obviously loaded Class 8's have to struggle to pass you to keep their 10mph, and I know they're tugging 70 plus.
Now the CAT 3126 in my FL-60 would have pulled this entire truck and the Sportchassis together faster, but from my reading, this turbocharged DD should be putting out similar power (300ish).
This is going to be a long first post...sorry...
One thing I noticed on my other TD's was a lot more turbo whine than I'm hearing with this one. In fact, I can't hear the turbo running at all (and there's no boost gauge as found). Of course, the motor and the turbo are mid-vehicle, so there's that.
Suspecting this, I pulled over on my first voyage and pulled the intake hoses and did verify that the impeller turns smoothly, and was indeed spinning even at idle...so hmm.
it felt ok for what a big beast it is (man...like twice the size of the one on my CAT).
800mi of sheer torture later, I have it home and have been on the conversion for a couple months, but in the back of my head I'm knowing that I'm going to have to address this power issue before it goes back on the road (and I may end up living in it for awhile so it matters).
Ok, Ok, so here we are (and thanks).
Some Googling about increasing the power of the DD led me to understand that increasing the injector size was the most common route (no idea what I have... I think I have moped injectors). This in turn provides more boost because of more combustion.
Right off the bat, this strikes me as an antiquated way of increasing power.
You see, every TD I've had (well I own a 300hp gas turbo bike too) utilizes a waste gate in it's turbo setup. I've never owned a TD engine that didn't.
The idea is that you can over boost the engine to increase horsepower and then manage egt's and such as required.
Nobody in my former world just dumps more fuel in to see a resulting boost increase after the fact. That seems so wasteful (or waste-gate-less) in my eyes.
While I wish I could give you numbers, I haven't yet installed a boost gauge or an EGT gauge (I will), but man... it feels like the truck didn't come with them because there was no point in it (i.e.... so little boost that it wouldn't matter)
I am used to a healthy diesel screaming away up a grade... making dogs wince miles away...etc. With this I hear nada, and that makes me wonder?
I did ask a friend about this who is a diesel freak, and he said the DD's don't whine much. My logic tells me that there isn't really a way to make a hard working turbocharger "not whine much", but maybe a lethargic one?
Again, sadly, I have to compare with the CAT 3126. That motor was getting 10-15 pulling 24k, and as much as 18 unloaded.
Taking a motor that's getting 7mph and slow as heck, and just dumping more fuel in...I'm really hoping isn't the best answer.
We are all living in a world now where our MPG matters quite a bit.
That said... first actual question...
Is there a way to increase and manage the boost to the DD 6-71?
I had wondered if there were waste gate turbos that could be installed, and possibly some electronics added for management? Could one use a 8-71 turbo...do those put out more air?
Secondly, I'm looking at both water/methanol and propane injection.
Being an in-progress RV conversion, I already have a 30gal propane tank ready to install.
Thirdly, maybe there is something wrong with my motor (as in some system in it not functioning and causing sluggish power or ?
The question here is how does one find that one-eyed master of all things DD who knows what's wrong with the system as you're pulling up?
Simply taking it to the local shop, I suspect would end up being pricey and without satisfaction. Where is the guy who knows how to get the most out of this motor?
With so many around for so many years, there must be one in each state?
(I'm on the west coast by the way).
What I'm looking for is a path... change this, add intercooler from a Kenworth... get this kit, add water... chant... whatever.
I figured some bus owners have discovered out how to get these things to pull a hill without worsening the fuel economy so here I am!
Thanks for listening!
Sean
hello and welcome. Was that a medical coach? as in Mobile CT Scanning Coach I have seen them used that way it should make a good house car :)
Check the tag on the valve cover the injector size should be there if not pull the valve cover and check the tag on a injector The 6L71T with 75 injectors was 275 to 290 hp with 801 ft lbs of torque 80's will get you close to 300hp, if you have 70's or 65 it will be in the 260 hp range the inter cooler will help but you will need to change turbos or you defeat the purpose of the inter cooler
Where on the west coast are you located those little guys lose 2% hp for every 1000 ft above sea level fwiw
good luck
Robsedona,
Correct! Ex- CT scan mobile.
However, there's a lot to converting these things (and what you end up with), that isn't obvious when you first jump in.
Time will tell if I will decide that converting a bus was a better idea.
Aside from the very odd layouts and onboard systems, they are lead lined (and it's not removable), so they're heavy. Also... no windows!
I'm all good for the post apocalyptic fallout though... I suppose.
What they DO have that makes it work for me is a side lift gate (patient gate), and I have an aging Great Dane who appreciates this, as well as a motorcycle that rides along.
Beyond that, it's a beast. It's the testosterone RV of the park... if you're willing to be open minded and deal with some odd looks, a different RV experience, and some major hurdles in doing a conversion.
Anyway...good guess!
Luvrbus,
Thanks for the response but I'm so new to this that I wouldn't know *what* to change the turbo *to*.
:)
(edit: I'm on the coast...Southern Oregon for the moment)
What is the serial number of the engine it may have a after cooler a 6L71T does not a 6L71TA does
good luck
Luvrbus,
I don't have that printed anywhere, and it's dark out now, so crawling under there will have to wait until light.
However, having inspected the engine, I have not come across anything that looked like a air/water heat exchanger. The intake is pretty straight forward... air cleaner / Turbo / manifold unless they hid something in there pretty good.
I appreciate the info' on the injectors, and I will find out. Still, that seems to be the standard route of increasing power with these, and to this I am shocked. I mean, this is a very popular engine even today simply because of the #'s of them out there and I have a hard time believing there isn't some aftermarket system that does more than dump more fuel into it.
Honestly, I can't wait to install a boost gauge... but then again, my perceptions of boost come from the 4 stroke world, and I wouldn't even know how a 2 stroke would react to being force inducted beyond what was considered practical at the time?
I mean... if I install a sensor and it's reading +2psi, I wouldn't know if that's right, or even if adding more would grenade a 2 stroke.
What I do know is that generally the most powerful and fuel efficient engines are getting some serious air, and it doesn't feel like this is, so that's why I started with the questions about alternative turbochargers and perhaps waste gated ones.
If that's not an option, then I'll look at methanol or propane, or whatever anybody else uses to get up the hill.
:)
Sean
Sean,
Welcome to the RV conversion madness ;D There are members on this board that know the Detroit Diesel 2 stroke engines inside and out.
If you haven't done so already, check the throttle linkage. I had the same symptoms on my bus-- constant high idle and very little power under load. The throttle linkage was binding causing the throttle to not open past 50% and then not return to idle. The Detroit Deisels got a bad reputation for being under powered when the real problem was often poor throttle adjustment.
It may also be worth checking the fuel lines for a partial blockage. It is possible the pick up tube inside the fuel tank picked up a piece of rust. A partial blockage can have the same affect as a stuck throttle that only opens 50%. If you do check the fuel lines, the fuel system will need to be primed before the engine will start again. Also, keep in mind there are one way check valves on the lines and an orifice on the return line.
Another thing to check-- Make sure the fuel shutoff lever is fully open when the engine is running.
When diagnosing a problem that can have a million different causes, it is best to start with the inexpensive basics then work your way up as you gather more evidence. It would be foolish to turn up the HP if it is not getting enough fuel because of a poorly adjusted throttle, half closed fuel shutoff, or a piece of rust stuck in the pickup tube.
Edit: Also, the tubo won't make much boost if the engine is only getting enough fuel to operate at half throttle. You really should be able to hear the turbo working on a long steep grade.
~Spark
Thanks spark'
I will check all of those.
The thing is though... I'm getting 7mpg highway, and I more or less have the thing floored to get to 60mph on a flat, so that fuel is going somewhere.
I don't know how the busses compare to my 34,000lbs and MPG, but maybe that's normal? Ack... I hope not.
What I'm afraid of...either by changing the injectors, or freeing up the throttle linkage or lines... is that somehow it's possible to get even less MPG that I currently am. Right? I mean "it's fixed", and I can get up a hill, but I'm getting 5mpg?
Put another way, it is the combination of lethargic performance *combined* with poor fuel economy that makes me hope the solution is air related, not fuel. Seems to me if things were in order, then at 7mpg, I'd be flying up the hills even at 34k (I would be in my FL-60).
Now I don't want to come on here and ask the impossible. If that's how the DD is, then that's how it is, but I have been on other boards where the ol' truckers claim to be pulling 80k up the grades at *almost* what the 4 strokes were doing, and I can tell you that if this rig weighed 80k it would be going backwards only. :)
The marine guys report 435hp out of these things, but they never say exactly how they are achieving it. MPG (or GPM in that case) is important even there. Are they just over fueling them as well?
I guess I was hoping someone would say "Oh yeah...Banks Power has a kit... 100+hp... we all use it". Remember, I came from Dodge/Cummins where you threw in a chip.
One thing though... you say that you hear your turbo. I don't. It's part of the reason I really need a gauge. Because of the placement of the engine, combined with the fact that I'm basically sitting on top of a whining hydraulic fan motor, I can't really be sure.
Trust me, I've stuck my head out the window on the highway and listened for that pitch, but I can't be sure.
I know the class 8's have boost gauges in their 6-71 powered tractors... does anyone know what the "normal" boost range is, and has anyone ever replaced the turbo with something that made more?
I know that my understanding of TD's is that if you give it more fuel, it should be getting more air....usually first... not after the burn.
By the way Spark'... going down the road, I can floor it and max out, but then I can *stand on it* and get a little more, so that throttle linkage sounds like it might be an issue and I'll check. Still.... 7mpg/34k/slow/flat?
Here is the vehicle we are talking about.
I will have a lot of interesting stuff to share about it in return for everyone's gracious help.
I call this photo "Top Speed"
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Sean -
Most 40-foot coaches with 2-stroke Detroits and Allison automatics average 5.5 - 6.5 mpg, both in revenue and RV service.
Thus your rig is in the fuel mileage ballpark.
Torque is what gets you "out of the hole" and "up the mountain" - and a 6L71T is lacking compared to 4-stroke motors.
Marine HP ratings of the 6L71T are accomplished with huge injectors, big turbos and a whole lot more cooling capacity than you could ever stuff in your rig - it's called the ocean!
Rear axle final drive ratio will have an effect on fuel mileage, any idea what you've got?
Wind resistance plays a rather large role, especially when you're trying to push a vehicle with the aerodynamics of a brick thru the air at 65-70 mph.
The combination of 34,000 lbs, an in-line six with no torque and a slushbox transmission = 20 - 25 mph up Rocky Top. Simple physics.
Depending on the turbo, some produce as little as 5 psi on a 2-stroke (smoke turbo), others can produce 25+ psi of boost. More boost = more heat = more cooling capacity needed.
Sorry to be the bearer of depressing news, but such is life in the two-stroke Detroit world.
FWIW & HTH. . .
;)
Most interesting, at this point, I am leaning toward finding a shop/mechanic who KNOWS how to work on the 6-71T engine, it is true, they tend to be on the weak swide, that does not mean dead, yours sounds closer to dead.
Things I would be interested in are why does it idle at 2,000 rpm ? :o
What is the rear gear ratio.
Your 34,000 lb should not be such a slug, have driven 6-71 non turbo, with 48' trailer, yes it was not pulling grades like a 350 Cummins, but it was not all that bad as your describing, why I feel a proper mechanic is highly needed.
I know it can be made better with the factory standard parts (injectors), would also be looking at the plumbing of turbo, make sure all the exhaust is going thru the turbo, and all the pressurized output if getting into the airbox and no leaks. Any leaks would surely kill the performance, A boost gauge is nice to see what is going on, Exhaust temp gauge is not a big need at this point.
Everyone has ideas, but being a Detroit Diesel lover, I know it is suffering from poor mechanics.
Good luck
Dave M
Hi Sean,
You have all the systems of a less than good performing exhaust track.
Tie a ten gallon garbage bag over the exhaust pipe end. Have someone hit the starter - you should immediately see the bag fill.
If not, begin your search just before the muffler.
Sean, Some of our buses came with a damper valve plumbed in the air intake for shutting down a runaway engine. It could be partially closed or getting sucked closed under heavy throttle. Again, it is worth checking as many possible external problem sources before diving into the internals of the engine. Like the others have said, a hole in the intake or exhaust can create as much of a problem as a blockage. When you have eliminated everything simple and cheap, it will be time to hire a set of experienced hands for checking compression, injector adjustment, and power balance. An oil sample test can give you clues about the condition of the engine before opening it up. One word of caution, stay out of the governor box. Messing with the governor will cause more harm than good.
By the way, your RV conversion looks like it is ready for battle. I am jelly ;D
~ Spark
My propane injection on my 6v71 is amazing on hills and grades for keeping speed and actually passing vehicles. The full install is on my site. Here is a video Home made detroit diesel 71 series propane injection system (http://www.youtube.com/watch?v=vShXGzxuOko&sns=em#)
It's not a risk free solution but I love it on my little 6v71N, a T install should perform even better.
Your are going to need the injector and turbo number that engine should have the 3 numbers 1 letter injector like 7C75 and something like S4H-005 for the turbo get those numbers or serial number and we can help with engine power. The after-cooler if equipped is under the blower hard to spot but that year model should have one fwiw it could be 245 hp one never knows without numbers Unlike your Cat engine the 6L71 the peak torque is 1600 rpm or above so keep the rpm up @ 7 mpg it doesn't seem like it needing much attention it is probably a CA smog engine if the truck was based in CA
The marine world does do 450 hp with a 6L71 problem they are 2000 hr engines which gets you 80,000 miles on the open road.If you are close to Bakersfield Ca ,my friend Don Fairchild can help you he is in the process of moving now so it make be awhile I would stay away from the propane with a turbo 6L71
A 200 kw generator on the 6-71T at 345 hp does well with good radiator cooling, we service a few of these, they are now dated, but keep on keeping on.
Dave M
Unlike a boat or a generator you are not chasing hp the torque is what you are after
Agree, but one interesting point of any DDC 2 stroke 71 or 92 series doing a generator load bank testing, they make the Cat, Cummins and the 60 series look like wannabee contenders when the block load test happens, the 2 stroker only has a very mini blimp in rpm, where the "Big boys" fall on their face big tine, from 1800 rpm 60 hertz down to under 43 hertz. Opps HP or Torque, I call it immediate available HP/Torque, that demo will make a believer out of a hard core Cat/Cummins fan ;D
The big boys can handle the load as long as it is step loaded, not 100% in one step like the 71&92 can handle so nice.
Dave M
I like the 149 series on a generator load those babies up they don't even change tunes
Wow, it's great waking up to a ton of useful information...thanks everyone!
First, ok... now I know that my 7mpg is not *half* of what this rig should get. That helps.
Then I read the part about my 2000rpm idle and thought "wtf is he talking about?". Ooops..typo. My bad. It idles about *1200* rpm. Sorry about that. I guess I'm excited!
Also, forgive me for using the measurement of hp. That's just being lazy. Usually I try to use "power", but I'm aware that it's mostly torque getting me down the road.
I'm kind of getting my feet on solid ground about where to start. Ya know, this motor is unlike any TD I've owned...even to look at it.
I crawl under there and it's sideways (and cramped)... it's got 3 times the hoses and filter housings, and unfamiliar steampunk looking devices on it than I've ever had. There's really a lot of it and it's hard to tell what is motor related vs motor dependent (hydraulics and such).
Luvrbus, I will get under there as soon as possible for those numbers.
I'm actually pretty mechanically inclined (in case anyone cares). I'm a machinist and a fabricator (I own a machine shop). I've done many engine swaps and mod's...etc etc. I'm just telling you that if it helps you gauge my ability to work on things and so that when I say things like "this engine has all this stuff I'm unfamiliar with", that comes from a person who has worked on his own diesels (things like changing injector pumps...etc), not from a soccer mom.
Luvrbus, I purchased this rig in CA, but I don't know if it was originally a CA truck... probably so, and I would be interested in meeting this mechanic.
I would trade an 80'000mi lifespan for 425hp by the way. I estimate 5000 miles per year of driving tops, and 16 years of pulling hard would be longer than I've ever owned a vehicle. What I couldn't trade in that equation is if it were getting less than 5mpg, and I would imagine that comes with the deal?
The same formula kind of applies for the idea of adding water/methanol or propane. I have heard stories that either can eat a turbo, or perhaps affect the valves, but if those also would get 80k down the road before servicing, I could stomach that.
I will tell you that I won't go 10kmi down the road the way it is without doing some kind of mod's if it's otherwise functioning properly.
In other words, if I get it to someone with experience, and they find the air leak, or bang on the mystery box until it unsticks, and get it running as it should, then I will do *something* to it if "as it should" is close to this.
Maybe this will help... running from Los Angeles to Oregon, there wasn't a bus that didn't pass me on any grade, and most of them pulling trailers. Some of them likely had older DD's so I'm just "feeling" that I'm underpowered.
It's hard to determine "normal" on a new rig...unfamiliar engine... odd chassis and purpose...etc.
I also understand that you guys are giving 100% to try to do the impossible, which is diagnose my issue without standing in front of, driving, or having any experience with the rig, or me as a person. For all you know, it could just be me. I really appreciate that effort and I know what's it's like because I've done the same thing helping people with things I do know a lot about.
It might very well just be a combination of things.... CA truck.. the gearing...ridiculously large full time running hydraulic fan, stock injectors, too many auxiliary systems...etc. I mean, this truck was set up to haul a CT scan machine from hospital to hospital...likely without much freeway time. It was built by people who build fire trucks and airport emergency vehicles with no regard for the cost of fuel in those equations, nor "giddy up".
So where I stand now with your help is that I'm going to check some stuff as suggested, get some numbers, get to a mechanic who knows the DD like the back of his hand, and get it fixed or Ok'd, and work from there on ways to improve the performance beyond stock if still required.
My experience with the commercial diesels is that getting down the road often has as much to do with the transmission as with the motor.
My 3126 CAT for instance just kind of did its thing while the 6 speed Allison in that rig did all the work. The tranny made up for a marginally strong motor which is a very efficient setup. I will have to look into this as well, that the tranny is making good use of the power the 6-71 comes with.
I would like to research the different injectors once I have my baseline. I've read there is a series that atomizes better.
Also, I'm curious about the blower (err..sucker), which if indeed in an exhaust scavenger, would be a limiting factor in the usefulness of applying more boost prior to combustion.
Oh, to address some comments on exhaust restriction... I don't need to put a trash bag over the exhaust and watch it fill. Starting the truck makes enough smoke for the 1st 30 seconds until it stops hunting that I could probably fill a box of trash bags. Plenty of air moving both in, and out. No run-away damper that I can find (I have a stainless steel bowl that fits the intake just in case).
One other thing that I'd like to say while I'm here is that I am surprised at the lack of "upgrades" obviously available to this motor.
I don't mean that to sound like a whine, but as an observation. With so many years of service, I was expecting to see at least a few "kits" or "packages" available on the open market. Rebuild kits with stronger components that let you get that 425 with some longevity...etc.
It's just something I wanted to mention.
I better get back to it. I'll have so many more questions as I learn my way around. Thanks everyone!
Sean
Luvrbus,
I managed to slide this plate off the valve cover. Maybe it helps?
I can't read any #'s off the turbo yet, but I'll get in there with better light and try soon.
Thanks
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well the data tag says the turbo is 701
the injectors are 7G75
6A0432271
Model 10678642
My guess is you are not geared for speed.
I think that those numbers will aid the guys who have that info in their back pocket.
PS guard that tag with your life.
Note also outfits like Banks are not any use to you...DD is where you'll find what you need or guys like Clifford or Don Fairchild
Engine model # decoder: Note 42 is not a standard 40 = pre 1991 motor and 45 =firetruck
http://2-cycle.mtu-online.com/extras/engine-model-number-decoder (http://2-cycle.mtu-online.com/extras/engine-model-number-decoder)
Your engine details:
1-Engine Series: 71
06-Number of Cylinders: 6 Cylinder
7-Application: FF-Auto
8-Rotation & Type: RD
6-Design Variations: TA
40-Specific Model: Pre-1991 Engine
42-?
45-Fire Apparatus
Heres a better one:
http://engine.od.ua/ufiles/DETROIT-Model-Serial-number.pdf (http://engine.od.ua/ufiles/DETROIT-Model-Serial-number.pdf)
The serial # confirms that it is probably the original motor
6A0432271
431867 being the first produced motor in 1983'
I'm thinking I'd be looking for a metal tag stamped with oversize rebuild data....or think about doing one.
More than ever, I strongly suggest he find soneome who loves the DDC 2 strokes, it will then wake up.
I went (15 years ago) over a 6-71 in a 4104 that had about 1500 miles since the big tubeup at Steward Stevenson in Houston, 4 valve head, valve clearence varied from .010 to .032 bridges not close, rack would not fully open etc etc, He claimed it was very weak. Next time I saw him, he complained about the poor fuel mileage, but it ran & he could pass trucks! Asked if he wanted me to set back to way it was ? HELL NO, I rest my case.
Dave M
You say you want to install a turbo boost gauge. I did this last year for my 6V92TAC (that's the Californicated version of the TA) - I bought a VDO 30PSI gauge from Summit Racing, ran half a mile of 1/4" plain nylon airline from a convenient 1/4" FPT outlet on the side of the blower below the turbo all the way to the gauge, and got a kick from seeing it show 26PSI boost under full load. At least, until two weeks ago when I was driving along I-15 to Buses Gone Wild 6 for our annual get-together, when there was a loud PSSSST, and after the initial panic of thinking my brake system was kaput I realized that the gauge was showing no boost. The reason was because the very hot air had melted the DOT fitting's O-ring and the nylon airline. Doh! I've now put in a compression fitting (no O-rings to soften) and ten feet of copper tube before the nylon airline, to hopefully cool the air enough that it won't melt the plastic airline. We live and learn!
FYI, my friend's mid-engine Crown tandem with a 270HP 6-71TA and a non-overdrive 10-speed and 4.1 axles gets 10MPG, but it weighs only in the mid-20s now. It climbed up Tehachapi out of Bakersfield in 8th and 9th gear, passing every truck on the climb. As others have said, you have to keep a 6-71 singing - it bogs down below about 1500 RPM, so you need to manually shift an automatic to keep it happy (and cool).
John
Sean,it is 285 hp with a after cooler and you have the good injectors the G's are used with std timing no need to advance the cam gear the timing is built into the injectors.
I would have a tune up done making sure they do the governor setting even the starting aid, with the spring loaded fuel rods the governor should not be hunting as it is called.
Tune it up set the rpm @2500 so it does not faint looking at a up coming grade or hill drive it till croaks and that maybe a long time with a 6L71. The exhaust temp (EGT) will tell you a lot about the engine if you have a good IR temperature gun lay or stand up a board at the exhaust pipe not covering the pipe run it @ 2100 rpm you should have a reading of 760 to 780 degrees
good luck
Your coach sounds like it may have some Crown Supercoach or Gillig pedigree. Have you considered taking the Cheap and Maybe Easy way out of this power dilemma and repowering your coach with a suitable ex Crown Supercoach pancake Cummins engine?
Reason I ask is that right now in California, again lots of Crown Supercoach ex school buses are being placed out of service. Some have perfectly good 250-290 hp/ 800 tor Cummins Big Cam or NTC type pancake engines. Four stroke 855 models. Available $CHEAP$.
An older Big Cam 2 pancake engine can be easily re configured with factory used parts to as much as 475hp/1500 tor. With a different turbo and some intake, radiator, charge cooler and exhaust mods, you can get an $easy$ and safe 550 hp/1650 tor. A tranny change required.
Edit; I meant a 600 series Allison and NOT a 6000 series. My bo bo. Proof reading comes to mind, which I did not. Sorry for the error.
A 6000 series Allison will not hold up. You need a HD740 Allison. Or...with some modifications, a properly sized New World 6 speed with two overdrives will work and free up some driveshaft length also, plus greatly increase your road speed. PEM if 'ya wanna. HB of CJ (old coot)
I think the rig has actually some relationship to Oshkosh...probably the most overbuilt chassis imaginable. It sure looks Oshkosh by gosh to me :)
John, I'll be looking for that fitting myself soon. Gauges make the truck go faster!
Luvrbus, I'll be right over, how much beer should I bring? Errr.... how much beer do I need to bring to get 375 with no fuel economy or longevity hit? ;)
HB, I was looking around at what the repower options were for this "L" motor. Even having done many automobile swaps though, 2 minutes under this truck and I let that fantasy go. It's just so integrated in there that it would be immense reengineering. The plumbing alone is daughting. That said, what is the model of Cummins you speak of? I might consider it when i blow this one by not listening to Luvrbus's advice (which everyone tells me is a good idea to do) ;)
A couple quickies...
Are there any electronics in this motor? I've read about the DDEC motors. Advantages/Disadvantages? Conversions?
I have a 701 turbo I guess... which means nothing to me. Is this the best one? Is there a "best one"?
Also (this should be it's own thread), my hydraulic fan comes on all the time. However it is "controlled". After I start the motor, there is a delay of between maybe 3-30 seconds and it kicks in (and it's loud like my forklift steering). It's pretty random and I can't tie the trigger to anything.
It never shuts off though and it's a big mutha', so I know I'm losing some fuel there.
What is odd to me is that it is controlled, yet comes on and stays on when the engine is cold, warm, hot, whenever.
Before I start tracing this maze of hydraulic lines and magic boxes that they connect to, is there a reason why the fan would be intentionally on all the time instead of thermostatically controlled?
I'm looking for this to be a problem to fix, but I don't want to get it kicking in at 200 degrees just to find out that it needed to be on all the time to cool something else (like the Allison). Could it have been set that way because it was a CA truck in hot weather that they didn't care about the fuel economy? Thoughts?
Henry,I think you have typo in the 6000 series won't hold up those are a monster off road transmissions 5 ft long and weigh about 3,000 lbs I am guessing you meant 600 series ?
good luck
Quote from: eagle19952 on June 08, 2014, 07:30:24 PM
I think the rig has actually some relationship to Oshkosh...probably the most overbuilt chassis imaginable. It sure looks Oshkosh by gosh to me :)
...or at least designers that went to the Ruski military school of truck design.
Actually I have a lot of fun with it. I get questioned all the time. People even pull over when I'm fueling and ask "um..what is that??".
My best friend says I need to buy a white anti-exposure suit with the positive pressure ventilation tank and pull up in front of outdoor cafe's and jump out pointing some geiger counter looking device at everyone, then say to my wrist "still below fatal levels", and jump back in and drive off! LOL.
I'm such a jokester in real life that I've started doing it when people walk up.
The last time I was fueling and a guy walked up and asked about it, I said it was a FEMA radiation interdiction vehicle and that he shouldn't get too close because it was mildly radioactive.
He took off so fast that I actually had to chase him across the station and tell him I was kidding...and apologize.
In person it's a pretty intimidating vehicle. No windows...13' tall, and it is definitely built Oshkosh-like. The two massive HVAC's on the back look like jet packs or some kind of transformers. You can make up just about any story you like (So far I've done CIA, NSA, FEMA...etc), and not once has anyone got the joke. I need to stop! :)
If I end up full timing for a bit in it, maybe it will keep the Walmart security from wanting to approach?
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fimg.photobucket.com%2Falbums%2Fv500%2Ftwomarbles%2FIMG_3907.jpg&hash=55a0ca63f3b54fb40007567ea3d77e37c5c32a68)
The 701 is the group number it will be S4H-005 unless it has been changed with a A/R of 0.96 it's good for low end and mid range power not much on the high end for power and torque Call Don @ 661-391-4520 Monday he is close and he knows the 6L71 one of his favorite engines,he will take time to talk to you
I looked at that setup before on a unit for sale here a engine swap not for me they look like the built the truck around the 6L71 ;D
good luck
Quote from: luvrbus on June 08, 2014, 07:59:34 PM
I looked at that setup before on a unit for sale here a engine swap not for me they look like the built the truck around the 6L71 ;D
Exactly, and thanks for the #. I will get ahold of him, but it will be a month or so since I'm in the middle of moving.
I look forward to meeting Don and will tell him you sent me.
LOL may work for both he is in the middle of moving his shop
Liftgate service for tuning? Hmm... I was a machinery dealer and have my own machine shop I'm loading (10 tons loaded, 20 tons left).
Maybe I should call him :-)
While I figure out the right place to post this, maybe you guys will find this mildly entertaining...
I figure it sort of fits here since this is my introduction thread.
I hope you will still talk to me after seeing this!
Trimmed2 (http://www.youtube.com/watch?v=Hwdjh9sIpbQ&feature=youtube_gdata_player#)
Cheers!
That is a nice looking rig!
Next time you are asked what it is, put on a suspicious look and answer: "Did you see the Men in Black movie?
In my humble opinion, you might lose several tons of that useless lead ballast, which would boost your power and mpg. Also losing weight might allow you to run only two tires on your rear axle, as opposed to 4, which would also reduce weight and drag. There has to be a way to get it out. There always is.
And if you post an idea of your location, I am sure somebody around these awesome forums can help you out with some ideas.
Quote from: Mex-Busnut on June 08, 2014, 08:51:18 PM
That is a nice looking rig!
Next time you are asked what it is, put on a suspicious look and answer: "Did you see the Men in Black movie?
In my humble opinion, you might lose several tons of that useless lead ballast, which would boost your power and mpg. Also losing weight might allow you to run only two tires on your rear axle, as opposed to 4, which would also reduce weight and drag. There has to be a way to get it out. There always is.
And if you post an idea of your location, I am sure somebody around these awesome forums can help you out with some ideas.
Well you're right about that. I've looked into it and it's bonded and difficult to remove.
I've decided to wait until the whole Russia/Ukraine thing settles down before removing the lead shielding (I'm a little nuts as you'll learn).
I would post my location, but I was sued over a night club I was opening and lost my house...which led me to buy this thing because I have no idea where I'm going to live in a couple months. As soon as I land, I will attach that to my profile :)
The last build of the 8V-71TA from Detroit was 400hp with 1200lb/ft torque. That used 7G80 injectors-which would be the biggest I would go with an automatic. That would translate in your 6-71TA to 300hp and 900ft/lb torque. Couple of things-does the engine have a bypass blower? If it is a TA (Turbocharged Aftercooled) you could remove the aftercooler and use instead an air to air intercooler. I did that on my 8V-71-just went from 65 to 75 injectors and it really woke up the engine.
Also make sure your Allison torque converter is locking up. Depending on the model, either in 2nd or 3rd. With your turbo engine, you probably have the MT647 that locks up in 2nd gear. And just like the bigger 700 series, you can have a manual lockup solenoid installed (I have one on mine) so you can also get torque converter lockup in 1st and 2nd-great for mountain driving. Good Luck, TomC
Sean,
It's a brick aerodynamically. At steady-state road speeds above 25 (yes, I said twenty-five) miles per hour, your fuel consumption will get steadily worse as speed increases. This is not a straight-line function, so you won't notice a major change till 40-45 mph. At 60 mph, fuel consumption is going to suck and it doesn't matter what you do to the current engine or if you change engines.
I am curious about the complex plumbing you describe and all the auxiliary systems the vehicle has -- are all these things being powered by the 6L71 in addition to motivating you down the road ? That could make quite a bit of difference.
edward
Quote from: shelled on June 08, 2014, 09:27:05 PM
Sean,
It's a brick aerodynamically. At steady-state road speeds above 25 (yes, I said twenty-five) miles per hour, your fuel consumption will get steadily worse as speed increases. This is not a straight-line function, so you won't notice a major change till 40-45 mph. At 60 mph, fuel consumption is going to suck and it doesn't matter what you do to the current engine or if you change engines.
I am curious about the complex plumbing you describe and all the auxiliary systems the vehicle has -- are all these things being powered by the 6L71 in addition to motivating you down the road ? That could make quite a bit of difference.
edward
A brick it is. No argument there.
I wish I could describe the aux' systems... I'm intentionally being vague because I haven't had the time to trace it all out and determine what it is.
I will give you an example though... the hydraulic line for the fan and PS has at least 5 individual hoses that go through at least 3 boxes, 2 of them mechanical at one solenoid based. There's T's that split off that go rearward to who knows what? It's overbuilt, and over complicated.
I suspect it's pressure relief or bypass valves...and diverters...ugh. They are all black..lol! I think the hydraulics have their own filters too.
That's just to power what i can only guess is only the PS and fan. It gets worse. Then there's the hydraulics for the gate and levelers (which is an independent system). Everything under there is serious. The levelers will lift the entire truck (all 10 wheels) right off the ground without straining. Then there was all the stuff left over from the CT scanner installation... miles of wires, 300a 480v service and transfer switches and transformers, and line controls You could power a residential block with what I've already pulled out. The shore power cable weighs over 200lbs!
This thing is an exercise in ridiculousness that I can only imagine would be matched by a fire pumper truck.
The confession I have to make though is that I dig that it's built like this. Months of fun figuring it out!
After I discovered a couple chips in this white paint, I realized and confirmed that the entire outer skin of the truck is stainless steel (rivets too), as well as a good deal of the inside. The door seals are all "Sea-Lok" commercial stuff.
I don't really expect it to ever be "lively". It is a brick, and a tank, and obviously was designed to carry this massive magnetic machine over mostly surface streets, but I got a great deal on it, and it's in great shape, and it scares me a little...which is fun.
:)
Quote from: Audiomaker on June 08, 2014, 07:33:17 PM
HB, I was looking around at what the repower options were for this "L" motor. Even having done many automobile swaps though, 2 minutes under this truck and I let that fantasy go. It's just so integrated in there that it would be immense reengineering. The plumbing alone is daughting. That said, what is the model of Cummins you speak of? I might consider it when i blow this one by not listening to Luvrbus's advice (which everyone tells me is a good idea to do) ;)
Sean,
That thing is definitely a project for the for the advanced RV converter/maniac! ;D ;D I say that as someone who has done a few of those myself. The two happiest days of your life with that will be the day you acquired it and the day you get rid of it. ;D
A little free, unasked for, but I hope heeded, advice:
This board & some others have people that represent over a thousand years of experience (collectively) with DDs, buses, trucks, and machinery in general. I myself have 50 years of experience, and there are others who are equal or better.
That said, Clifford (Luvrbus) and Don Fairchild have forgotten more than I and a lot of the rest of us will ever know about DDs. Hook up with one or both and take their advice on engines. It will save you a world of money and time.
There have probably been folks that have asked you to machine or fabricate something for them in your shop that you knew would not work as they hoped; but, they insisted and you complied. Your experience and knowledge could have saved them time and money. Use Clifford & Don's knowledge and experience to save yourself some disappointment; AND use your experience and knowledge in other areas to save us some!
On another note, I have a used Motosat DataStorm F2 satallite dish I will sell you cheap if you REALLY want to freak people out. ;D It comes with a brand new, yellow radiation warning sign! :o :o :o
Have fun!
TOM
Quote from: oldmansax on June 09, 2014, 05:01:49 AM
Sean,
That thing is definitely a project for the for the advanced RV converter/maniac! ;D ;D I say that as someone who has done a few of those myself. The two happiest days of your life with that will be the day you acquired it and the day you get rid of it. ;D
A little free, unasked for, but I hope heeded, advice:
This board & some others have people that represent over a thousand years of experience (collectively) with DDs, buses, trucks, and machinery in general. I myself have 50 years of experience, and there are others who are equal or better.
That said, Clifford (Luvrbus) and Don Fairchild have forgotten more than I and a lot of the rest of us will ever know about DDs. Hook up with one or both and take their advice on engines. It will save you a world of money and time.
There have probably been folks that have asked you to machine or fabricate something for them in your shop that you knew would not work as they hoped; but, they insisted and you complied. Your experience and knowledge could have saved them time and money. Use Clifford & Don's knowledge and experience to save yourself some disappointment; AND use your experience and knowledge in other areas to save us some!
On another note, I have a used Motosat DataStorm F2 satallite dish I will sell you cheap if you REALLY want to freak people out. ;D It comes with a brand new, yellow radiation warning sign! :o :o :o
Have fun!
TOM
I totally agree Tom, and I hope my questions don't come off like the new kid who has to be contrary to everything....including tried wisdom.
At the same time, on the BBS's, a little devils advocating is not only social, but helps me (and the newbies that read these threads later) have a better grasp on how things work (or don't) because they heard all the arguments for and against. Unfortunately that is often tedious to those who have well earned their status as "being in the know".
For myself, I try to at least back up my thoughts. I have a good quarter mil' invested in a machine shop that isn't for hire. It only lets me create what falls out of my head so when my head goes "can we do it this way?", I can try it if so compelled.
I guess what I'm saying there is that there are some who ponder the alternatives endlessly because it's free to do so, and for the most part, it is free to tap the minds of others on the net who have already invested. Those people are often met with rolled eyes because it's the 5 year old repeating the word "why?" to every response.
I kind of come from the angle that I really need to understand something fully to accept it, but once understood, I'll help others to understand, or create a new way to do it, or prototype a new product to consider.
If you really want to increase horsepower on a 6/71. You need to make your way to Mill Springs North Carolina and see Gene Russell.
uncle ned
Just how fast are you willing to afford ? Its just a $$$$$ thing.
Local wacko balanced his 8V-92, cleaned up heads, port matched exhaust manifolds, 145 injectors, unknown turbo that make massive boost, Governor at 2800 rpm, in a Senicrusier.
How bad do you want the big power ?
Dave M
Quote from: wg4t50 on June 09, 2014, 11:41:58 AM
Just how fast are you willing to afford ? Its just a $$$$$ thing.
Local wacko balanced his 8V-92, cleaned up heads, port matched exhaust manifolds, 145 injectors, unknown turbo that make massive boost, Governor at 2800 rpm, in a Senicrusier.
How bad do you want the big power ?
Dave M
Sitting in my driveway I could care less. Having to pee for 2 hours on a 6% and I'm ready to sell the wheels.
Browsing the net, I'm not the first guy to roll along wishing the DD had a little more go, and I doubt I'll be the last.
Nobody expects these things to haul butt up a hill, and in fact, like most drivers pulling large trailers, or heavy loads, I expect to come to a crawl at times and throw the flashers on.
There is a point though where it borders on not being drivable. It's the point where you've moved out of the slow lane onto the shoulder and the 80,000lb-ers are having to exit the shoulder back onto the road to get around you. I'd say dropping under 10mph on a 6% or so.
Best guess... from moving a DT466 from 220 to 250hp, and moving a CAT 3126 from 250hp to 300hp, and having towed 45' trailers loaded with each... I think this thing needs about 350 to get in the game, and 375 to make it pleasant.
That's still under the 400 or 450 danger zones for this engine from what I'm understanding, and it doesn't have to be a dummy light engine (ie...I don't mind watching a EGT on the panel). Yeah... about 350-375 in the 900-1000lb/ft range would work, and be worth a few mod's without going too crazy (including mod's that preserve the motor at that rating).
Luvrbus pointed out a housing with a different A/R that might be better suited since he implied it worked better at the top end...which is currently where I'm always at now. 2000rpm on the hill, 2000 rpm @ 60mph... just turn it on and put it at 2000rpm until you get there really.
A tad more air and maybe some injectors sounds like a good solution. I can't yet bring myself to more injector without more air (I'm still fighting that in my head).
Still no word on water/methanol injection for the DD. I have some questions about that into the manufacturers regarding any problems with that system on a 2 stroke.
Like I said before, maybe I'll blow this one up in a year or two messing around. If I still like the truck at that point, maybe a balanced and blueprinted hot motor might go in? Gotta see where life takes ya. :)
Agree on slow & needing to pee ! However as I get the picture, your vehicle is suffering from lack of a mechanic, nothing in good order will run the speed your talking about. Hell a 318 DDC with 73,280 lbs runs 28 mph on mountains, that is slow, not " under 10 mph".
Don't think you can wish your way to running better, find a shop that likes DDC engines and geterdone, you will be happier. Forget the 425 hp outa that critter, that is a dream.
Dave M
Quote from: wg4t50 on June 09, 2014, 04:19:30 PM
Agree on slow & needing to pee ! However as I get the picture, your vehicle is suffering from lack of a mechanic, nothing in good order will run the speed your talking about. Hell a 318 DDC with 73,280 lbs runs 28 mph on mountains, that is slow, not " under 10 mph".
Don't think you can wish your way to running better, find a shop that likes DDC engines and geterdone, you will be happier. Forget the 425 hp outa that critter, that is a dream.
Dave M
Yep... will get in touch with "Don" asap. I might be headed through his area soon.
Don't think I ever said anything about 425hp tho'. 375? 350?
And yeah... 10mph up the grapevine outta Los Angeles. I think there's a 7% grade in there somewhere. Floored at 2000rpm in whatever gear would keep me moving. Kept my speed most of the time with the loaded trailers. You always know the heavy trucks, but yeah, they're pulling 80k with the same fight that I'm pulling 34k. Never overheated though... I'll say that.
Quote from: Audiomaker on June 08, 2014, 09:58:46 AM
I don't mean that to sound like a whine, but as an observation. With so many years of service, I was expecting to see at least a few "kits" or "packages" available on the open market. Rebuild kits with stronger components that let you get that 425 with some longevity...etc.
It's just something I wanted to mention.
Sean
I think is where I got the idea about the 425 hp dream ?
Agree, get it to a known mechanic indeed.
good luck
Dave M
Quote from: wg4t50 on June 09, 2014, 05:28:04 PM
I think is where I got the idea about the 425 hp dream ?
Agree, get it to a known mechanic indeed.
good luck
Dave M
Ah yes. Sorry, that was what I was expecting to find on the market since such things are available for other engines. It was just leading to the idea that for such a popular engine, there doesn't seem to be a lot available pre packaged for this one.
As for my actual idea of what makes the truck serviceable... about 50-75 more than what it already has... whether that be by fixing it, or adding to it, and I only mention those numbers to get feedback on whether that is a big custom job to get, or just a couple tweaks (I'm trying to prepare myself and my budget).
Cheers!
Here's my take:
If you do twelve things at once you'll never know where the improvement came from.
Get/check a tune up, that'll set your baseline: valves and injectors settings
Be sure and short the injectors while your there, listen for gross difference...no difference then you found a weak cyl.< (injector, valve or rings/piston or all of the above)
Go drive it.
Set the governor up another 2-250 rpm no load.
Drive it.
Still not happy twist the gov to 2325 max.
If there is no remarkable/noticeable improvement Re-gear it
Having said that I wouldn't even touch the motor until you've told us what the final gear ratio is.
If it's as low as I think it is your wasting your time until you re-gear.
Then after you know the gearing, start thinking about the turbo.
AND BEFORE ALL THAT...well consider that a 1983 model motor just might need rebuilt, My 1978 is no virgin and as much as it sounds like that motor has spent against the governor I'm willing to bet it needs some TLC.
I have never seem a DD motor that did not have at least the oversize rod bearings stamped some where on a heavy metal coupon that would stick out like a sore thumb.(Every rebuild I have done or saw has it)
If it ain't there That motor has to be tired there is no way that it can't be.
what are the gear ratio.
Quote from: eagle19952 on June 09, 2014, 07:19:31 PM
Here's my take:
If you do twelve things at once you'll never know where the improvement came from.
Get/check a tune up, that'll set your baseline: valves and injectors settings
Be sure and short the injectors while your there, listen for gross difference...no difference then you found a weak cyl.< (injector, valve or rings/piston or all of the above)
Go drive it.
Set the governor up another 2-250 rpm no load.
Drive it.
Still not happy twist the gov to 2325 max.
If there is no remarkable/noticeable improvement Re-gear it
Having said that I wouldn't even touch the motor until you've told us what the final gear ratio is.
If it's as low as I think it is your wasting your time until you re-gear.
Then after you know the gearing, start thinking about the turbo.
AND BEFORE ALL THAT...well consider that a 1983 model motor just might need rebuilt, My 1978 is no virgin and as much as it sounds like that motor has spent against the governor I'm willing to bet it needs some TLC.
I have never seem a DD motor that did not have at least the oversize rod bearings stamped some where on a heavy metal coupon that would stick out like a sore thumb.(Every rebuild I have done or saw has it)
If it ain't there That motor has to be tired there is no way that it can't be.
what are the gear ratio.
Eagle, I am in complete agreement, and as others have said, the first step should be to get it to a wise DD specialist.
The problem is that I'm moving and I have at least another month involved in completing it. Add to this that there's a time limit to get my shop and stuff moved because the reason I'm moving its that I lost a lawsuit (over a commercial lease), and they are taking my house I paid cash for in full out from under me (ugh).
Just so everyone knows, I'm basically living in this thing parked outside of the house I'm trying to move from... in preparation... and I'm trying to also covert the very basics of this truck to live in because that's all I'll have time for before the sherif comes.
To make matters worse, my "house" is an old school, and it's 33,000sqft including a 8000sqft machine shop, and I'm doing it by myself...which is really slow going.
Being as forthcoming as I can, I agree with everyone here that I should get this truck to a mechanic to find a baseline, but all I can do for the moment is read as much as I can, and ask you guys questions.
I'm getting a lot of great information here. I'm figuring out about where my truck should be... about what can be done to it simply... about what my expectations should be...etc. I'm very grateful. If nothing else, at least when I get to that mechanic I will have a vague understanding of what he's telling me.
Anyway, as for the rebuild, I was told it was rebuilt in 2000. They did not have paperwork. I bought it from a mega-million dollar medical imaging company who really didn't seem to have too much interest in the sale of this truck. So little interest in fact that it doesn't seem like they'd lie about the rebuild. Everything else they described to me about the truck before picking it up in person has been better... in fact much better than described so I wouldn't be amazed to find that rebuild tag under there somewhere.
Also, the truck doesn't feel like the engine is tired. My DT466 was a tired motor...smoked...vibrated randomly..etc. This starts right up and is pretty clean when running. I dunno.
I just found another tag...
The transmission is a MT-654CR
The tag also has the engine model (6L-71TA), so after all that Sherlocking, it was right there. I feel like a boob. Just overwhelmed folks.
No gearing information on that one, but I'll hunt around some more in the daytime when I can.
And again... I'm sorry for asking all the questions about propane and methanol and such. It doesn't mean that I'm going to rush out an do that stuff without following the correct path first. I'm just curious and wanting to learn everything I can as soon as I can.
Regards
Sean
In the meantime... maybe this will help...
Around 1900-2000 @ 60. Almost can hit 70 on a flat given cool air, 10 minutes tryin', and an RPM of about 2100ish.
?
:)
Quote from: Audiomaker on June 09, 2014, 08:09:22 PM
In the meantime... maybe this will help...
Around 1900-2000 @ 60. Almost can hit 70 on a flat given cool air, 10 minutes tryin', and an RPM of about 2100ish.
?
:)
That sounds like 4.1 axles. I get 67 MPH at 2100 RPM with a 4.1 and 12R22.5 tires. At least your transmission ratios are slightly closer than a regular MT transmission's.
Get that lead outa there. You need to put your bruck on a diet.
John
Quote from: Iceni John on June 09, 2014, 08:35:18 PM
That sounds like 4.1 axles. I get 67 MPH at 2100 RPM with a 4.1 and 12R22.5 tires. At least your transmission ratios are slightly closer than a regular MT transmission's.
Get that lead outa there. You need to put your bruck on a diet.
John
I will. I am going to need to install another door soon to create an inverter compartment, and at that point I'll be sawing into the side of the rig and will get to see how "stuck" this stuff is (this is encapsulated lead sheeting used by hospitals and such...reported to be safe).
I think I'll have to approach it a section at a time from the interior. It's all riveted...yay. Will have to drill out the rivets in a panel to open it...uninstall electrics and such that run over it... pry it out or whatever, cut insulation and reinstall.
If I just took off with a drill right now I probably wouldn't have much of a rig left to live in, so I'll either do it a panel at a time, or wait until I have a shop again.
Emphasizing the positive, it's a nice resounding "thud" to close a 150lb entry door ;) Feels very solid.
Should have mentioned about the 28 mph on mtn with the 318, that is exactly why I installed the 12V-71 in the MC7, never found a mountain after that.
Never been a happier kid with clothes on ;D
Dave M
To get really crazy, you could pull the lay down 6-71TA and install two 4-71's end to end with a HT740 (shorter then your transmission). Then you could safely have 400hp and 1200lb/ft torque.
Some will say that doesn't work as exampled by the first drive train in the PD4501's. But you have to remember, the Scenicruiser was running the two engines side by side with a hydraulic coupler. You'd be running the engines end to end drive shaft attached as one engine.
Detroit during WWII made a quad 6-71 marine engine. It was rated at 900hp max and 650hp continuous. What was unique was that you could throw the clutch, turn off one engine while the other three were still running. Good Luck, TomC
Agree, the DDC combinations are near endless and beautiful setups, have sperience with a twin 6-71 common gearbox with Twin Disk clutch setup, could run the generator on one while servicing the other. The fun was matching them for hp, exhaust temp etc. Another good old days memory, maybe the beginning of my DDC joys.
Dave M
Quote from: TomC on June 10, 2014, 08:38:10 AM
To get really crazy, you could pull the lay down 6-71TA and install two 4-71's end to end with a HT740 (shorter then your transmission). Then you could safely have 400hp and 1200lb/ft torque.
Some will say that doesn't work as exampled by the first drive train in the PD4501's. But you have to remember, the Scenicruiser was running the two engines side by side with a hydraulic coupler. You'd be running the engines end to end drive shaft attached as one engine.
Detroit during WWII made a quad 6-71 marine engine. It was rated at 900hp max and 650hp continuous. What was unique was that you could throw the clutch, turn off one engine while the other three were still running. Good Luck, TomC
Tranny change? Uh oh.... let me guess... MT-645CR is only rated to 286hp? (1 extra)...lol.
If this gets any worse, I'm gonna build an island in my galley (which is right over the motor), and stand a CAT up in there.
Designers really need to stop under powering commercial trucks. I've been through this before.
I think your problem is the engine is not getting full throttle they will reach full rpm and still not be getting full rack and your first Detroit is going to take a few driving lessons for you to get the hang of it IMO ::)
good luck
Thanks Luvrbus. I have this feeling that once it's gone through and a few gremlins are caught, that I'm going to love this motor.
All the whining is just me being social ;)
Hate to cross post, but in parallel to figuring out the motor, I'm also having to work on the other aspects of making this a conversion.
I just started a thread in the "projects" forum if you guys want to see what this motor will be pulling around.
https://www.busconversions.com/bbs/index.php?topic=27527.0 (https://www.busconversions.com/bbs/index.php?topic=27527.0)
Thanks Everyone!
Donald, I thought those were built by the Crane Carrier Co in Tulsa OK
Do not think I ever saw a CCC that could be under 50,000 or 25,000lb cab & chassis, always under some real heavy trucks, like the FWD & Oshkosh. ;D
Dave M
Donald, I thought those were built by the Crane Carrier Co in Tulsa OK
maybe but I was thinking that Hendrickson provide the chassis which I thought was affiliated with Oshkosh...maybe not in 1983
he says it's a Hendrickson/Calumet....I am guessing it has walking beam suspension...whoever made it .. it looks Oshkoshy to me.. complicated by engineers...
These kinds of rigs never get built by users or drivers...they always send the freaking book keeper...:) and the guy inside doing the medical stuff probably follows along in a limo...:)
from google:
In 2001, AK Associates acquisitioned one of its competitors Calumet Coach Company to forming Oshkosh Specialty Vehicles, the largest mobile medical manufacturer in the world.....Calumet City, IL.
from Hendrickson...
Other truck manufacturers come to Hendrickson for truck sub-assemblies, or even the entire vehicle with the customer's own label. The new Ryder truck is one of these. The Manitowoc crane carrier is another. The Cline Truck Company of Kansas City, Missouri, bought some of Hendrickson's sheet metal for its trucks. Hendrickson also built chassis for International fire engines.all custom-engineered and hand-built. Lifetime production of Hendrickson (trademarked) trucks is estimated at 5500 units.
But I have been known to not know the whole story...:)
I saw some crazy stuff coming out of CCC in Tulsa in 30 years like the Mack garbage trucks with the Scania engine and the Dinia funny looking oil field cab over truck and some I never heard of going to Turkey and the mid east
This is a shot of the suspension...as well as I can get my phone to take it....
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fimg.photobucket.com%2Falbums%2Fv500%2Ftwomarbles%2FIMG_4594.jpg&hash=8b2cd8ce4bd3af0eea6b4e3ae8cf4d4d5f1cfa9a)
you know what, you might post pictures of your dash controls...looks like some kind of axle inter lock....need more info. you might be driving 2 axles in places you only need one...
I forgot about the hydraulic leveling jacks those had I see one in the photo
That's Neway air suspension. Usually rated at 46,000lbs for the tandem. Great suspension in that it has an upper trailing link that prevents torque up of the axle. The only draw back is the arms are low to the ground and getting hung up on a curb is not out of the question.
Your idea of making a stand up engine maybe the best. There was a mid engined motorhome chassis for using on garage motorhomes. It used a Cummins ISL at 450hp and 1250lb/ft torque. And actually, it didn't stick into the cab. The interior reminded me of a boat since there was a hatch in the floor for top of engine access. Good Luck,TomC
Quote from: eagle19952 on June 10, 2014, 03:28:42 PM
you know what, you might post pictures of your dash controls...looks like some kind of axle inter lock....need more info. you might be driving 2 axles in places you only need one...
Yes... does have. The switch seems to work (Light when you turn it on... PShhhhh...when you turn it off). I keep it off course, but if it were possible that it weren't releasing... that's one to keep in mind.
Quote from: TomC on June 10, 2014, 06:18:28 PM
That's Neway air suspension. Usually rated at 46,000lbs for the tandem. Great suspension in that it has an upper trailing link that prevents torque up of the axle. The only draw back is the arms are low to the ground and getting hung up on a curb is not out of the question.
Your idea of making a stand up engine maybe the best. There was a mid engined motorhome chassis for using on garage motorhomes. It used a Cummins ISL at 450hp and 1250lb/ft torque. And actually, it didn't stick into the cab. The interior reminded me of a boat since there was a hatch in the floor for top of engine access. Good Luck,TomC
That's good to know TomC. It does hang low, but then again, so does the motor. Probably take out the oil pan first.
Quote from: Audiomaker on June 10, 2014, 07:20:06 PM
Yes... does have. The switch seems to work (Light when you turn it on... PShhhhh...when you turn it off). I keep it off course, but if it were possible that it weren't releasing... that's one to keep in mind.
well that is being used properly:
http://www2.dana.com/pdf/AXDR-0130.pdf (http://www2.dana.com/pdf/AXDR-0130.pdf)
I meant to say "I keep it off of course".
Taking "of" out gives a whole new meaning ;)
Your pinion seal is leaking pretty good, add that to the list.
Quote from: TomC on June 10, 2014, 06:18:28 PM
That's Neway air suspension. Usually rated at 46,000lbs for the tandem. Great suspension in that it has an upper trailing link that prevents torque up of the axle. The only draw back is the arms are low to the ground and getting hung up on a curb is not out of the question.
Your idea of making a stand up engine maybe the best. There was a mid engined motorhome chassis for using on garage motorhomes. It used a Cummins ISL at 450hp and 1250lb/ft torque. And actually, it didn't stick into the cab. The interior reminded me of a boat since there was a hatch in the floor for top of engine access. Good Luck,TomC
Walking around the truck checking my jacks.... look between the rears and yep... Neway casted in.
The rear has a surprisingly soft ride...even by air standards.
If the front is just leaf springs, there is a two air bag (small) kit made that has a cab mounted valve that you can adjust going down the road. In this way, you adjust the pressure until you get the best ride. I'll be putting these on my truck conversion. Look at http://www.donvel.com/ (http://www.donvel.com/) Good Luck, TomC
Quote from: TomC on June 12, 2014, 07:29:28 AM
If the front is just leaf springs, there is a two air bag (small) kit made that has a cab mounted valve that you can adjust going down the road. In this way, you adjust the pressure until you get the best ride. I'll be putting these on my truck conversion. Look at http://www.donvel.com/ (http://www.donvel.com/) Good Luck, TomC
Thanks for that link, Tom. Just what I've been looking for!
Quote from: TomC on June 12, 2014, 07:29:28 AM
If the front is just leaf springs, there is a two air bag (small) kit made that has a cab mounted valve that you can adjust going down the road. In this way, you adjust the pressure until you get the best ride. I'll be putting these on my truck conversion. Look at http://www.donvel.com/ (http://www.donvel.com/) Good Luck, TomC
Yes it is. The ride is actually pretty good as stands. On it's maiden-to-me voyage, I drove 900mi without any discomfort on pretty hard non-air ride seats and was surprised. I suppose you bus guys are used to it, but the front seat ride is a little different sitting a good 3' in front of the axle.
I have a set of air ride seat bases I pulled from a toter I used to own prior to selling it. Those will be going in once I have decent seats to go with them. The link you provided has an "anti bounce attachment for those, so thanks!
We'll see after awhile if I want to do some mod's to the front suspension. I have often toyed with the idea of semi-air in the front (removing about half the springs and installing bags (which I also have extras of). As for "control", I'm not really having any issues... I'd hate to introduce any. The big old thing tracks pretty straight even over rough highway.
What I *will* want to do is get under there and see if there's maximum travel limit on the steering (that's adjustable). A little tighter turning radius would be great.