Coach Cooling System Modification

[WorkingOnWise]

tekebird wrote "you will not gain any appreciable efficeincy running at 195-205 even if you don't crack your heads."

Thats what I'm going for, increased efficiency.

"Don't you think the big room full of engineers might have an edge on you as well as the rest of us in the engineering department."
I thing a group of engineers had an advantage over the general population 60 years ago, but no, I don't think that the group of engineers that designed the 6V71 engines 60+ years ago have any advantage over us today. We have so much more information, information that simply didn't exist then, to draw from now. They did awesome with what they had to work with. We have much more to work with now, and we can do better.
It's not cocky to think that way, or derogatory to them. It is just the nature of how knowledge increases.

[tekebird]

I saidf you WILL NOT gain any noticable effiiciency.

as for the room full of engineeres 60 years aaago.......that would be about the same time that the SR-71, and the XB70 as well as a whole bunch of very advanced aircraft were designed.........true they did not care about efficiency then.........

but you can't ahve both worlds......simplicity and efficiency do not go hand in hand normally.........that is why they have  computer controlled things with $400.00 sensors and you need a $2000.00 code reader to find out what is wrong.

How do you intend on making your 4519 to test prior to youu adding on to it?  Are you also going to fabricate all the appropriate test jigs and telemeetry sensors so you do it right?

With what you intend, there are two options that make more sense

1/ Buty a straigh truck with a box....easily insulated and you can stretch a truck frame easily...and it will still tow any trailer you want.

2. Build from the ground up using components from the 4519

you have yet to enlighten us to your engineering background, fabrication abilities etc.

I am sure a bunch are curious.......as you are not the only person who has ever popped in with grand ideas........most have disappeared...likely after they had a mental breakdown after spending all their money and a bunch of their life building something that either could not be built....or was well beyond the scope of their abilities.

I will be curious to see your results.

[pvcces]

WorkingOnWise, do you have any idea how many horsepower the fan takes? What do you think you will use for electrical power to run that 25 hp fan?

That's why it's so heavy. It also has a big effect on fuel economy. The two stroke will need 1 1/2 gallons per hour of fuel at full power governed speed just to run the fan in the factory setup.

This is one reason why the fuel mileage doesn't fall more than it does when running the coach in near freezing weather; while it takes more effort to push the coach in cooler weather, it takes less effort running the fan.

Our coach got 10 mpg on two of the fillings on our last trip. We were running 65 mph, so we were burning 6.5 gph. At 140,000 btu per gallon, we were producing some 910,000 btu per hour, with around 300,000 btu going into the cooling system.

With no ram effect over the radiator, it takes a lot of energy to pull enough air over the radiator to get rid of the heat. What do you suppose will happen if we hit a mountain grade and start burning 14 gph while climbing?

That's what the big fan and radiator are there for.

Good luck with your project.

Tom Caffrey

[WorkingOnWise]

tekebird...the SR71? It leaked worse than a DD 2 stroke when it was on the ground! Engineers today would be able to build it so it didn't leak fuel as a normal operating mode! Thanks for making My point.

"you have yet to enlighten us to your engineering background, fabrication abilities etc.

I am sure a bunch are curious.......as you are not the only person who has ever popped in with grand ideas........most have disappeared...likely after they had a mental breakdown after spending all their money and a bunch of their life building something that either could not be built....or was well beyond the scope of their abilities."

I came here with grand ideas, yes. And grand questions. Looking for Grand and honest, and Informed answers. And a willingness to listen and consider each one.
So what is your coach like? Cookie-cutter copy a a thousand others with a personalized engraved plate on the dash?

Do not try to belittle my skills or ideas unless you have the drive to get out of you own little comfy box first.


pvcces - I would like to learn more about the fuel consumption you discussed. Is there a link you can give me? Or is this personal experience? It almost sounds like I should lose the fan and replace it with a pair of electrics, because the fans can be off when running down the highway if I duct the radiator properly, and let the electrics do the work at low\no speeds. This soulds like a way to save fuel, is I understand you correctly, that the fan consumes about 1.5 gph at highway speed.  Did I miss something?

[tekebird]

First nobody is trying to belittle your skills.  Just trying to get you to think resonably.

The SR 71 was designed to leak...and if designed today it would leak by design too.....the DD was not and a properly maintained one does not.  What about the Xb70...it didn't leak.

Drive to get out of my box........I think thow should not talk bullshit untill you produce product my freind.

pretty much everyone who has replied has told you the problems with your ideas...and offered good solutions......if you are such the engineer you should not need any links for the Fuel use  PVCCES discusses....and you ought to read......as the electrical draw for the fans you intend to use are huge....and thus also cost fuel, and are less reliable than a mechanical fan system......

No Need to reply to any of this as I have lost interest and desire to give you any logical guidance

[TomC]

On the transmission and rear end.  I am a new truck salesman for Freightliner and have many factory reps to lean on for my bus project.  I too wanted to have a two speed rear end, but the bottom line is that Rockwell, now Meritor, just did not make one.  And there is not enough room between your trans and axle for one.  I highly recommend that you chuck the 2spd trans in favor of the Allison V730- that is still in use today with parts still being made.  Remember-when travelling, there is nothing worse than breaking down but to find that the broken part is obsolete.  Whereas the V730 is simple and can be worked on by any Allison dealer.  When you get tired of going 10-20mph up the hills and overheating your engine, I'm quite sure you'll change you engine to the 6V-92TA with the V730.  You can take just so much humiliation and embarrassment with a slow bus being honked at going up the hill.  Plan on adding 2-3000lb to the bus for the conversion.  Good Luck, TomC

[niles500]

WOW - the reason you are getting a number of Nay votes on some of your ideas is because many of these people have already attempted some of the things you are trying to do and failed (not due to their knowledge and ability) and many Newbies have said dam the torpedoes I'm gonna do it anyway, never to be heard from again - these people, more than any you will find anywhere else, are here to help you fulfill your dreams (if possible) - they are merely trying to enlighten you on large hills (figuratively) you will have to climb to attain your goal - no one will tell you it can't be done (because many of them have and a whole lot more) - Here are some of the issues they are trying to enlighten you on;

1) you have a bus that may be underpowered for your intended use

2) your tranny may not be suitable for your intended use

3) the configuration of your drive train (not a V) may be a hinderance to the ability to find/install a 2 speed differential

4) the structure of your bus does not lend itself to slide installations

5) the structure and drive train of your bus does not lend itself to the towing of large trailers

6) the structure of your bus does not lend itself easily to any "stretching"

7) the initial cost of the vehicle pales in the amount of time and money needed to alter it from its initial intended use and capabilities

Please don't let this post be another Nay vote but just a little food for thought, and when you do decide to attempt these projects the people who are enlightening you now will be the same ones trying to help yout out of whatever jam you are in at the moment - some have posted an interest in your project and may be willing to lend a hand in your "experiment" - take them up on amy such offers as there is a wealth of knowledge and hands on experience to be gained from this group - HTH

[tucsontattoo]

Don't know much about all the streching and cooling system changes but I will say this. I have a 4106 w/ 8v71 w/ 75 injectors, 730 allison ( with more than 2 speeds) a trans cooler that i can turn on when pulling a grade. The air cleaners have been changed to paper element that I stay carefully on top of cleaning or changing. A pristene radaitor and rebuilt fan clutch. This engine has about 40,000 miles since its last major overhaul and runs sweet.
That said, when I leave Tucson headed for the beach with full fule tank and water tank (100 gals.) I have to fight her to keep her under 70 on flat ground. Making that pull coming up from the desert at octilla to Cajone ( the sign says 6% I figure it, based on milage and elevation to be more like 7 1/2 ) I'm in low at the top running about 25 mph watching my trans temp start to move into the yellow range (250) and my engine temp up to about 200. But if a fish bowl with a 671 and a 2 speed allison ever blows past me on that road i'll figure it was yours.
My thoughts. you have a fine coach there and your into it for almost nothing. fix every thing important, brakes, suspention, rebuild what you have. I could buy a bigger engine and trans, I could buy a bigger coach if i wanted to, then I could spend more time at work paying for it all.

 When I first got my bus I had alot of thoughts of doing alot of racey stuff to her, Now were use to each other and  I spend all my spare time driving her. We have put on about 15000 miles since last fall and are getting ready to do about 5000 more this summer. You could do like we do, plan you route on roads that don't have tough grades( we will be talking the 10 into California and staying off the 8 when we add the toad this summer) and the only  I,m thinking about addingbigger is the ice chest..........

           For what its worth.........................Tucson

[WorkingOnWise]

TomC, 2 to 3k lbs to convert from a 6v71/VS2 to a 6V92/V730? Wow that seems like a big penalty in weight. Where is the bulk of the extra weight from, the engine or the trans? I have had it in the back of my mind to look into another trans because the one I have has seen much better days. Slips bad in 1st...vert bad. Right now, it would not even move if I put it against a 4" curb. I'd have to get a little run at it, so the trans it a reasonable upgrade in my eyes because I am sure this one needs major attention. The engine however, has only 25k miles on it since its last overhaul.

niles500, I welcome the nays, as long as they are followed with some thought and reason, like yours are. Saying that it wont work because  really smart guys 60 years ago didn't get it to work isn't helpful. Thanks for your thoughts. They are helpful.

About the trans. I looked up the v730 after I read TomC's post about it being still produced and readily serviceable, and good parts availability. Seems like Allison got that trans right. I see it was used at least as far back as 1982. Thats a lifespan of 25 years. Impressive! I also see that the v730 was used in the Fishbowls with a 6v71, so it seems that I can put it into my coach, and if I still am not happy with it, I can slip in a 6V92T at a later date. Does that sound right?
If so, where do I look for good info on the v730 and purchasing one for my coach.

[Sojourner]

WorkingOnWise......you quoted "......you have the drive to get out of you own little comfy box first" (unquote).....I am with you......I've been there & still am. I don't believe in not trying to do to make it better than it was in the past. Am not afraid to challenge anything in working with fabricates & machining metal, plastic, wood, electrical, plumbing and cad drawing. It is fun to see the outcome.

Experience is the name everyone gives to their mistakes.
Oscar Wilde (1854 - 1900), Lady Windermere's Fan, 1892, Act III
.

About radiator:
Tom is correct about "With no ram effect over the radiator,"
There is air wave on side of bus like ocean wave.....the faster travel the larger. Another word high pressure wave & low pressure wave areas along full length. Depending on traveling speed, it varies in pressure wave in radiator area. It is not like normal truck frontal area which is given more freely flow of air.

I agree to improve better air flow but electric motor has to be big enough to equal the OEM spec or greater air flow. Alternator will be robbing more energy than mechanical design system. DD 2-cycle is about ¼+ more BTU than 4-cycle.

FWIW

Sojourn for Christ, Jerry

[TomC]

I apologize, my post was a bit unclear.  Converting your engine/transmission from the 6V-71N/VS2 to the 6V-92TA/V730 will be at the most a few hundred pounds difference-mainly to upgrade the radiator, muffler, and air cleaner.
The 2-3000lb weight reference was to the total conversion of the bus.  My bus weighed 28,000lb without seats before starting.  After insulating, and all (including the generator), now weighs 31,000lb-so I added 3,000lb to the bus.  Considering my bus has a 36,000lb gvw (gross vehicle weight) rating, I'm still 5,000lb from capacity! (compare that to the nearly overloaded sticks and staples when you buy them, before adding a ton of personal stuff).  Hence, with my 11R-24.5 tires, I only run 90psi in them, and still that is a bit high.
Once again on my soap box- If you want the best ride, tire life, etc, weigh you bus in traveling form per axle.  Then look up on the tire inflation guide for your specific tire size and manufacturer for the correct tire pressure.  Those of you that are running using the maximum tire pressure printed on the side of the tire are just getting a fork lift ride-or better put-your ride would be much better at the proper inflation.  Good Luck, TomC

[WorkingOnWise]

Whew! Thanks for clearing that up TomC! I had visions of my coach doing wheels with all that extra weight hanging out past the rear wheels! LOL.

We have figured that we will be adding 5500lbs to the coach, which based on how many people I have seen theses things carry day in and day out when I rode them as a kid going to school, that's not a bad number. I don't have numbers on gvw so I am basing my numbers on bus weight with full fuel-all the seats and rails+all the stuff we want to add+full fuel and potable water=coach weight. As long as that number is less that bus weight with full fuel+(60 people*150lbs), we are fine. I choose the number 60 because for years I rode these busses in Detroit and they ran for several hours each day with that many people. And their performance was great, even with that load.

[prevost82]

Quote from Niles
[WOW - the reason you are getting a number of Nay votes on some of your ideas is because many of these people have already attempted some of the things you are trying to do and failed (not due to their knowledge and ability) and many Newbies have said dam the torpedoes I'm gonna do it anyway, never to be heard from again]

me thinks this is another one....

You bought a $100 bus and you are going to put $80K into and it will still be a $100 bus.

You have no idea (you probably think you do) on the hours, effort and money required, to complete a project this large. I have over 6000 hrs and $80K into mine and it's not done yet, and I didn't put any slideouts in or do any structual changes to it, other that to raise the roof, but none of the changes that you are suggesting .... I did my convertion in 2 yrs, working on it 8 hrs a day, 7 days a week, and worked my 8 hr day job as well. I haven't done anything to the bus in 2 yrs. I'm too burnt out to work on it, but it is 90% done for us to enjoy and will complete it in the nexst 2 yrs.

So many don't realize how large of a project converting a bus is .... I certainly didn't after the 1st month, all I had done was strip out the seats, washrm and floor ... I had to have a talk with myself and came to the conclusion that I had to work at this way harder to get it to a state where we could use it. (read ... so my wife wouldn't kill me for dumping 80K into something that we couldn't use or sell for more than 20K, because it wasn't completed).

If I were doing it now, from what I've learnt, I would buy that Prevost Marathon on eBay ... at the time I did my convertion that bus would have been double the price it's selling for now, so it was out of my price range. I believe prices of bus convertions have fallen considerably in the last few years.

You can find alot of these examples (uncompleted buses) on eBay for time to time and it's sad to see how much money the seller will lose because he bit off more than he could chew and couldn't complete the project.

Good luck with your project, but watch how much you bit off you may drown in it.

Ron

[tekebird]

glad I am not the only one that is thinking sensibly

[WorkingOnWise]

prevost82- Thanks for the thoughtful words. I do know that the reality of the project will not match the idea of the project. That's y we have spent 18 months doing research and study on these matters....to minimize the bumps and blocks we will run into.

I'm not trying to be confrontational, but I have an observation.
I have heard many people here and other places say how undoable what we want to do is, but no one has ever stated something like " I tried that and this is what happened." Every person who has said the structural changes I have proposed are not reasonable, even foolhardy, has based it on their own theory and learning, but none on real experience. Yes it is risky to totally redesign a proven machine, to try to make it into something it was not intended to be.
We here all understand enough about diesel engines to know that running it on veggie oil is at least possible. We don't need to do it to know it can be done. Many have tried and failed, but many have tried and succeeded. Even with all that, do you have any idea how many people told me I was gonna make a storage shed out of my coach after I blew the heads off or some other death event before I actually ran my coach on the stuff? Lots! None had ever tried it. They just figured that a diesel engine burns diesel fuel, and anything else was instant death. Of course, they didn't know that the first "diesel fuel" was actually peanut oil.
I have done things all my life that others have said are foolish, dangerous, and destructive. Sometimes they were right, sometimes not. My experience has been this. The ones that were right had some experience in the matter, and the ones that were wrong didn't, usually. There have been times that the ones with no direct experience were right, and vicea versa, but it is the exception, not the rule.

I want to hear from the wacko's that tried it and ended up with a $30k storage shed!

As for the 2spd diff, yeah, that will be interesting. ou all are right in that there is no room for one under my bus using existing geometry and off-the-shelf parts. I'm not sure I want a 2spd diff bad enough to design one, and then build it. It is definitely a phase 2 project priority!

With all that said, I am still 6 months from starting up the sawsall, so if there are still corrections to my plans needs, I have time. And I am listening. Even to you tekebird, even if you do think my meds need to be adjusted!  =)