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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Geom on June 05, 2016, 02:28:45 AM

Title: Weird heat issue
Post by: Geom on June 05, 2016, 02:28:45 AM
At least it's weird to me...

We've ventured forth into the mountains (after spending far too many months in relative lowlands). Making our way to CO, I've noticed an odd heat issue.
I've been monitoring the engine temps pretty closely on the bus and usually she runs about 185-190ish -when working moderately, climbing to shy of 195 when working hard (climbing a 6% grade on an 80 degree day for example).

Now that we've started this climb (somewhere near eastern KS), I've noticed that we've been running consistently at just shy of 190, a lot. Granted the days have been hotter (86 degree day for example), but it seems to be doing it even on 75 degree days -just not quite as often.

The temps seem to be directly related to speed, almost entirely.
If I slow down, the temps cool way down and I actually get to 180ish territory.
So at about 60 mph I'm at 190, but going even to 63,64 etc is enough to cause it to creep closer to 195 territory.
As we've been driving around, we've been pulling over a few times in a trip, both out of typical "trip" type stuff, along with trying to keep things cooler.
The second we pull into a rest stop or even pull over at an off ramp, the temps plummet.

We kept managing things this way and have actually done quite well. We covered a lot of terrain in a couple of days driving.
No complaints other than the temp issue. Although I have noticed an increase in oil consumption. Along with a few wet spots at rest stops. Nothing too terribly outrageous, I don't think.
Oil is around a quart every 200-250 miles. Sometimes more, sometimes less.
Overflow/blowby oil container thing is usually mostly empty.
I dump it occasionally and get maybe a solid trickle for a few seconds.
But that engine is dirty! As it does leak oil, a lot I think. It's unfortunate, but it is, and were managing. One "trick" to reducing oil use is by keeping the oil half-way between full and low (sometimes lower). That seems to significantly reduce usage and overall ... Splatter.

Today, however something new happened that has me more concerned. We'd made it into Denver and were just a few miles from our exit.
We were climbing what seemed like a fairly small hill (compared to some of the more formidable ones so far), and the temps climbed..
On to 195 in a hurry, then past 195...
Hmm, ok it's done this rarely before, even on this trip, but usually something like 196-197.
And it cools off right after its "hard workout" is done and comes back down pretty well.
This just kept going and now I was becoming concerned.

Navigating the serpentine uphill road, while trying to find a "suitable" exit and place to stop, and trying to control the temps, was certainly a harrowing experience.
I slowed way down, and down shifted to second.
I was pulling about 57-58mph and holding decent temps at first.
The grade did change upward, although not seemingly that much. But after shifting to second, I was doing about 45mph and about 1900ish rpm, and the temps just kept climbing.
Outside temps were low to mid 70s.
Fortunately, our intended exit was on a slow downhill.
I was able to back off of the throttle, pretty much entirely.
The temps started to come down quickly and we made the exit and navigated those serpentine and climbing roads, to our campsite, without much issue -albeit at much lower speeds of 15-20mph.

So that's what happened.
The temp ranges, overall all are not new. It's been pretty much this way since we bought it.
It's never really gone this far to the "wrong" side of the temps (195) before.
I don't think anything too terrible has happened and it eventually cooled right down after it got probably to 200-201.

What I want to know is, is this normal? Am I doing something wrong that I should be changing? Why does it seem to be so... temperamental?
And most importantly, why this new behavior?

I check coolant level fairly regularly -every trip.
And the surge tank is always at the right level.
We had the coolant (and a bunch of other fluids) changed at our last maintenance visit (In TN).
Used a ~55/45 mix of coolant and distilled water.
There are auxiliary cooling fans on the engine.
One is attached blowing air toward the radiator, and on into the engine bay.
Another is on the opposite side sucking air away from the transmission bell housing.
Another draws air from the top of the engine bay toward the bottom with 12v duct/fans (which move an impressive amount of air out).
So I would think there's ample "fresh air" movement happening.
Although turning the fans on/off doesn't seem to make that much of a difference when it's "working hard" -albeit some.
It certainly cools things way faster when we slow down or take an off ramp.

The transmission temps, on the other hand seem ridiculously low (below 140), often below gauge range. Hard to tell if that's sensor error or real. Sometimes it likes to climb to 160ish, when "working hard". But that is not an often occurrence, even at high rpm, or pulling a grade, etc.
The sender is attached to an oil return line and not actually *in* the transmission directly. That return line comes from an external cooler.
There is a secondary oil cooler/radiator attached to the main radiator (over the main radiator). 
That has the inbound aux fan blowing on it, then onto the main radiator underneath it, and then on toward the block.
Transmission oil is routed through that secondary cooler and back to the transmission housing.

Anyway, I'm going to dig into this some more tomorrow, -Checking different fluid levels, etc.
I suspect the coolant will be fine, and the oil might be closer to low; but we'll see.

Your thoughts, ideas, etc on this are appreciated, as always.
Thanks
George


Title: Re: Weird heat issue
Post by: niles500 on June 05, 2016, 06:35:22 AM
Check to see if your Tstats are functioning properly (fully opening) what type of coolant are you using? You are using straight 40 wt. Cf-2 oil? With all the auxiliary fans and coolers you have it is an indication that your bus has had cooling problems for quite some time - HTH
Title: Re: Weird heat issue
Post by: Runcutter on June 05, 2016, 08:25:07 AM
Do you, by any chance, have a "mud flap" under the rear bumper?  GM put flaps behind the rear axle, not under the bumper, to help create a low pressure area for heat to exhaust.  Some folks put a flap under the bumper to keep their towed vehicle clean, but that traps hot air.

Arthur
Title: Re: Weird heat issue
Post by: Dave5Cs on June 05, 2016, 08:29:39 AM
Hi George, are the gauges working correctly and does the one at the dash the same as the one in the engine bay as far as readings? Did you use a final charge coolant or just regular antifreeze? When going up grades do you down shift and keep the revs up or does it lug because that would let the heat raise. I always watch the tailpipe exhaust when climbing and if it is black smoke coming out then I shift from 3rd down to 2nd or even 1st and back off on the peddle, because it just ads fuel and heat with no real increase in speed. That will kill an engine faster than anything.
The oil problem you said that you lose less when between marks not fully full. You might check the marks on your stick. It should be about 1 inch below the top of the pan to engine block line. If you have to much oil in it the engine wants to get rid of it and throws it out. If your marks are off then you could just be refilling the overage amount.
Used to live in Colorado Springs for 10 years. Lots to see in the state. If you get up there go see Garden of the Gods, and Manitou springs. ;D
Dave5Cs
Title: Re: Weird heat issue
Post by: HB of CJ on June 05, 2016, 01:33:47 PM
Automatic or manual?  You indicated very low trans temps of 145F?  If an automatic then there is your clue.  Consider bad senders or gages?  Sender locations?  Wiring?  Your auto tranny should be cooking right along with the engine and usually take longer to cool.
Title: Re: Weird heat issue
Post by: TomC on June 05, 2016, 06:48:00 PM
Your temps are not too high.
Title: Re: Weird heat issue
Post by: oltrunt on June 05, 2016, 08:11:41 PM
I don';t really know very much but, on my MCI 8V92, I kept having the engine shut down for "over temp" and went nuts trying to figure it out.  It turned out to be that the nut securing the water pump impeller had loosened and the impeller wasn't turning-- the bus was cooling by "convection".  Jack
Title: Re: Weird heat issue
Post by: luvrbus on June 05, 2016, 08:31:29 PM
You muffler and air cleaner system can cause a 2 stroke to run warm,since it is a transplanted engine I would check the CFM on the exhaust and air cleaner
Title: Re: Weird heat issue
Post by: Geom on June 05, 2016, 10:19:07 PM
Thanks all for the ideas and suggestions.
Here's a summary of some of the questions/follow ups

The tstat appears to be working ok. It can sit and idle forever and not break a sweat (hi-idle). Even after running a bit hot it cools right down when no longer "working hard". So it seems like something is not keeping up, instead of a thermostat staying shut or open... To me anyway.
Is there ankther way to test the thermostat that I can try?

I'm using "conventional" full strength "heavy duty" ethelene glycol (whatever heavy duty means). But it's the stuff my mechanic uses in everything, Detroit included. It's diluted to a 55/45 mix with water.

Use delo 100 40wt oil, and have since we got it.

I do have the mud-flap(s) installed ahead of the engine bay and not under the bumper.

I believe the gauge (up front) is working. The one in the engine bay, however, is InOp. It's connected correctly to the probe, but never registers a temp. Never has. I've spent some time troubleshooting it in the past and haven't found out why. It's directly attached but I'm not sure if there's an electrical component to it I'm missing. If there is, I don't see it.

I've endlessly continued to try and cipher through the mystic runes of the sages, on what "not lugging a Detroit" actually means exactly. Along with "drive it like you stole it" or "drive it like you're mad at it", "how to push a screaming jimmy", etc, etc.
So I've settled on this. At no point does it ever smoke when I apply throttle, no matter how much I ask of it, except when starting from a dead stop. Then it smokes for a healthy puff and then all is clear. Otherwise I can mash the pedal and always get more power.
So what I've been using is speed to rpm. If I mash the pedal and I'm not able to maintain 57-58 with the rpm creeping below 1500, I slow down and force it into second. It will not stay in second and will up shift automatically at about 58-59. So when the situation calls for it, I just keep it around 54-55. That gets the rpm to about 1900-1950. Sometimes that seems to help cool it down, but surprisingly sometimes staying in 3rd and having it "pull" that tiny just long enough to be annoying little hill, doing 60-61 in 3rd; actually works better.
It just really depends on the length of the grade and what she feels like doing at that moment.
If that makes sense.
Bigger more obvious hills I always downshift and keep the speed ~55 (or slower depending on how steep, 45).

But generally I maintain about 1600-1800 rpm as long as she's got power to provide.

We looked into the oil capacity thing and I think the stick is right. We put in about 6 gallons of oil (and then maybe another .5 gallons) and that was enough for the filter. That shows the stick at half-way between. Putting more than halfway really does seem to make it spit (more) though. But regardless it's always got oil all around it.

It is a an automatic, v730. Sometimes the trans temp gauge will "hop" when it's working really hard. But usually it's just silent. It's mounted directly into the return line coming back from that cooler, and I wonder what the temp of that is at that point and whether it is a location error or gauge error. A new sender (and subsequent replacement effort thereof) are on "the list". I checked the wiring and it seems good and solid. I can directly tap the sender wire to ground and actuate the gauge up front just fine.

I'm intrigued by the water pump possibility. That might explain why it behaves so well under moderate load, but not heavier loads. I don't know how I'd test that. I do know that the water pump is capable of rotating the water through the front defrost core without issue. I would suspect convection alone wouldn't accomplish that?? Not sure if there's another water pump test?

The muffler (and other exhaust bits) is enclosed in a (very professional looking) heat wrap blanket to keep heat out of the engine bay. I'm not sure how I can test the muffler or air cleaner (I'm not sure where that even is). Any additional guidance there is appreciated on how to do so and what I'm looking for when I check it.


I did check the coolant and it is exactly where it has been since we refilled it weeks ago.
The oil was a little close to the low side of the stick. I suspect a 1/2qt will get it to the midway point again. Maybe a bit more than that.

I'll continue looking and take some of the suggestions above and do some more digging.

I also plan on moving that intake electric fan up a bit more and get it blowing more directly on the main radiator and not so much on the secondary transmission cooler. It seems like the trans is getting getting plenty of cooling with the external oil cooler along with the usual heat-exchanger cooler inside the engine bay...
But there's not currently a way to be certain with the gauge readings so far.

Thanks again,
George




Title: Re: Weird heat issue
Post by: eagle19952 on June 05, 2016, 10:42:16 PM
if you do not have an operational over-temp shut down... you will probably regret it soon or some day... if you do not..why not ?

you will definitely sleep better and type less if you do :)




Quote from: Geom on June 05, 2016, 10:19:07 PM
Thanks all for the ideas and suggestions.
Here's a summary of some of the questions/follow ups

The tstat appears to be working ok. It can sit and idle forever and not break a sweat (hi-idle). Even after running a bit hot it cools right down when no longer "working hard". So it seems like something is not keeping up, instead of a thermostat staying shut or open... To me anyway.
Is there ankther way to test the thermostat that I can try?

I'm using "conventional" full strength "heavy duty" ethelene glycol (whatever heavy duty means). But it's the stuff my mechanic uses in everything, Detroit included. It's diluted to a 55/45 mix with water.

Use delo 100 40wt oil, and have since we got it.

I do have the mud-flap(s) installed ahead of the engine bay and not under the bumper.

I believe the gauge (up front) is working. The one in the engine bay, however, is InOp. It's connected correctly to the probe, but never registers a temp. Never has. I've spent some time troubleshooting it in the past and haven't found out why. It's directly attached but I'm not sure if there's an electrical component to it I'm missing. If there is, I don't see it.

I've endlessly continued for try and cipher through the mystic runes of the sages, on what "not lugging a Detroit" actually means exactly. Along with "drive it like you stole it" or "drive it like you're mad at it", "how to push a screaming jimmy", etc, etc.
So I've settled on this. At no point does it ever smoke when I apply throttle, no matter how much I ask of it, except when starting from a dead stop. Then it smokes for a healthy puff and then all is clear. Otherwise I can mash the pedal and always get more power.
So what I've been using is speed to rpm. If I mash the pedal and I'm not able to maintain 57-58 with the rpm creeping below 1500, I slow down and force it into second. It will not stay in second and will up shift automatically at about 58-59. So when the situation calls for it, I just keep it around 54-55. That gets the rpm to about 1900-1950. Sometimes that seems to help cool it down, but surprisingly sometimes staying in 3rd and having it "pull" that tiny just long enough to be annoying little hill, doing 60-61 in 3rd; actually works better.
It just really depends on the length of the grade and what she feels like doing at that moment.
If that makes sense.
Bigger more obvious hills I always downshift and keep the speed ~55 (or slower depending on how steep, 45).

But generally I maintain about 1600-1800 rpm as long as she's got power to provide.

We looked into the oil capacity thing and I think the stick is right. We put in about 6 gallons of oil (and then maybe another .5 gallons) and that was enough for the filter. That shows the stick at half-way between. Putting more than halfway really does seem to make it spit (more) though. But regardless it's always got oil all around it.

It is a an automatic, v730. Sometimes the trans temp gauge will "hop" when it's working really hard. But usually it's just silent. It's mounted directly into the return line coming back from that cooler, and I wonder what the temp of that is at that point and whether it is a location error or gauge error. A new sender (and subsequent replacement effort thereof) are on "the list". I checked the wiring and it seems good and solid. I can directly tap the sender wire to ground and actuate the gauge up front just fine.

I'm intrigued by the water pump possibility. That might explain why it behaves so well under moderate load, but not heavier loads. I don't know how I'd test that. I do know that the water pump is capable of rotating the water through the front defrost core without issue. I would suspect convection alone wouldn't accomplish that?? Not sure if there's another water pump test?

The muffler (and other exhaust bits) is enclosed in a (very professional looking) heat wrap blanket to keep heat out of the engine bay. I'm not sure how I can test the muffler or air cleaner (I'm not sure where that even is). Any additional guidance there is appreciated on how to do so and what I'm looking for when I check it.


I did check the coolant and it is exactly where it has been since we refilled it weeks ago.
The oil was a little close to the low side of the stick. I suspect a 1/2qt will get it to the midway point again. Maybe a bit more than that.

I'll continue looking and take some of the suggestions above and do some more digging.

I also plan on moving that intake electric fan up a bit more and get it blowing more directly on the main radiator and not so much on the secondary transmission cooler. It seems like the trans is getting getting plenty of cooling with the external oil cooler along with the usual heat-exchanger cooler inside the engine bay...
But there's not currently a way to be certain with the gauge readings so far.

Thanks again,
George





Title: Re: Weird heat issue
Post by: TomC on June 06, 2016, 07:44:37 AM
When I increased my power on the 8V-71 from 300hp @ 800 torque to 375hp and 1125 torque by turbocharging, air to air intercooling, and increasing the injectors from N65 to 7G75, I had the radiator recored from 5 row straight fin to 6 row serpentine, increased the air cleaner from 6" to 7", changed the muffler to a turbo muffler, added an oil to air transmission cooler with thermostatically controlled electric fan before the normal shell cooler to take out heat that would be sent to the radiator. I still can over heat pulling a hill on over 85 degree day. I added essentially 2 misters that are drilled out to 1/16" that will bring the temp down in about 2 minutes of water. Not afraid to go anywhere now-mainly because I had almost stalled out a couple of times in the mountains-now no power worries. Good Luck, TomC
Title: Re: Weird heat issue
Post by: opus on June 06, 2016, 08:25:03 AM
Are you sure you have thermostats installed?
Title: Re: Weird heat issue
Post by: buswarrior on June 06, 2016, 10:11:41 AM
Air cleaner obstruction?

The higher you go, the harder it is to breathe, a less than clean air cleaner will raise engine temps.

Get an IR heat temp gun to confirm dash gauge. Open engine access inside, find the hot coolant pipe, shoot while underway, compare readings.

It will be noisey and windy back there with the lid open.

It is useless worrying any more, until you can be sure what the temps really are.
My MC8 shows 10 degrees rise on the dash when it's only 5 degrees rise at the engine, discovered this way.

happy coaching!
buswarrior
Title: Re: Weird heat issue
Post by: Cary and Don on June 06, 2016, 06:35:28 PM
I wouldn't move that fan.  If you move it it will be blowing against one side of the engine fan. The oil comes out of the transmission, past the temp sensor, to the cooler in front of the radiator, to the original cooler on the compartment wall, and then back to the transmission. The cooler on the wall will prevent the transmission from running too cool because the engine water runs through it and will warm the oil.

You need to take into consideration your altitude on these climbs. The higher you go, the harder the climb is for it and the hotter it gets. Have you used your misters when it climbs over 195 degrees?  If you get to 5000 feet you will notice a difference in the temps and power. We would flip those misters on if the temps got over 190 and we knew there was still hill to climb. Just flip them on and turn them off when the temps start to drop again. They feed from your fresh water tank.  There is a switch by the driver for the misters.

It has always spit oil if full so we kept in at half way between fill and full on the stick.

Don and Cary

Title: Re: Weird heat issue
Post by: oltrunt on June 06, 2016, 07:51:29 PM
Ditto on the over temp shut down!
Title: Re: Weird heat issue
Post by: Geom on June 06, 2016, 07:54:28 PM
Tom, thanks file the info on your situation. So that makes me feel quite a bit better. It had actually been running ok and manageable until that time it decided to just keep heating up.
We too have misters installed. They're currently InOp because of an earlier water tank snafu and replacement. I haven't replumbed them back yet, because we haven't really needed them... until now. But I had always intended on getting them functional "just in case", and I guess that case is now :)

When folks refer to the "air cleaner" is that the intake air filter/canister? If so, we replaced that at our last maintenance visit with a new one. So it should be ok, assuming no other unusual failure event. And it runs great otherwise so I doubt the filter medium/etc failed or collapsed or similar. But I suppose I can pull the intake on the turbo and take a quick peek.

I had been wanting to get an IR snapshot of the engine while running and post-shutdown for a while now. So I suppose now is as good a time as any. I'm assuming the best place to get an idea of temps is to shoot the return (top) water pipe going back to the radiator??

Don/Cary, thanks for the info on the tranny rad and the fluid flow. I had it backwards in my head. So if fluid is flowing out of the bell housing, into that line running to the rad (past the sender), then back around to the heat-exchanger in the bay; then in theory that should be the hottest point for that fluid (if not directly in the bell housing). Sometimes it... hops and reports a temp, fairly steadily (only when working hard), then quickly goes back down below guage scale range. So it's probably just a bad sender. I'll elevate the priority on swapping that out.
Thanks for the guidance on not moving the fan. I guess my thought there was to push more fresh air to the portion of the engine rad that doesn't have the tranny cooler in front of it, to better aid that section cool more. But that sounds like it might be a bad idea?
I plan on getting the misters working again. I'm going to replumb the way they were sourcing off of the fresh tank. We've since replaced the fresh tank, and I (intentionally) didn't hook that back in for a few reasons. But I did/do want the mister working, so my thought was to plumb in a one gallon water reservoir for the pump to draw from, instead of from the fresh tank as it used to before. That's on the agenda this week.

I've also been tossing around the idea of building some louvers, that I can position over the side cover of the radiator area, and angle them into the wind to draw more air and force it toward the rad. I'm thinking of maybe 2 or 3 angled pieces of plastic, or wood, or aluminum about 2 inches wide by 36 inches long, angled sticking about 1-2 inches up.
Thoughts on that?

We plan on making our way toward Colorado Springs next week and I'll for sure complete the mister project by then.
The louvers might take longer. I don't want them looking cheesy, so I'll undoubtably spend countless hours in analysis paralysis on it :)

Also, the InOp temp guage in the bay is simply a directly attached mechanical gauge. It has no linkage to the over-heat system, which appears to be intact and working to me.
I have a replacement on order, but won't be at a place where I can work on potential-coolant-leaking-out projects for a while.
I'm assuming that the overheat system has a different trigger in the engine (according to the manual it's a dedicated sensor/switch).

Thanks again all,
George


Title: Re: Weird heat issue
Post by: Cary and Don on June 06, 2016, 08:59:27 PM
Don't waste your time with the louvers. It had a set when we got it and they didn't make a bit of difference. And they were UGLY.

We plumbed the misters to the tank because we had a five gallon tank mounted down by the water pump for the misters. It went dry too fast. One gallon isn't going to get you very far. The mister heads didn't put out enough volume to work. We put those two little sprinkler heads on because it would drop the temp fast. The mister type heads we tried first tended to be so fine that the water didn't get to the radiator. It just blew away.

Better to have too much water on a hot day than not enough. Don't want to get stuck going down the road with the temp over 200 and no where to stop.

It does sound like the temp sender might be bad. The transmission should be about 10 degrees higher than the motor. If it's jumping, that sounds more like a wire. Those don't cost that much, just take it to a heavy  duty parts store.

Don and Cary
Title: Re: Weird heat issue
Post by: Seangie on June 06, 2016, 10:27:21 PM
I think you got plenty of info here.  If you are not breaking 200 you are not running over temp.  Especially at altitude...  over 5000 feet.

We are currently on the other side of the rockies (Durango) and when I get in the mountains I always have a hard time.  Usually because I cant always tell how steep the climb is.  Sometimes it will seem like Im on a flat yet Im losing speed and temps are rising.  I just had a heck of a time going through Santa Fe at 85 degrees in direct sun trying to keep my bus from hitting 205.

What Ive learned to do is to stop trying to figure it out and let the bus drive itself.  The most important thing is the higher the RPM the cooler the engine. 

Ive got a 6v92 turbo with a 740 auto.  If Im running at 55mph the 740 will naturally have me in 4th gear but my rpms will be low, like 1800 (Im guessing here as I dont have a working tach, just good ears).  If I have the slightest bit of incline, in 4th gear at that rpm itll start adding heat.  Not always alot (depends on the incline) but it will run warmer if I cant get those rpms up.  If I drop it into 3rd there at 55 Ill be at the very top of 3rd (22 -2400 rpm?) 

Now I can do 55 all day without adding heat until I start to lose speed... I dont force it.  Ill back off the pedal until I get to the point where it just barely starts to slow down and hold it there and let it decelerate naturally.  Someone told me to drive it like theres a raw egg under the pedal.  That helped me to understand it better. 

When it slows down to 37 - 36 mph, Ill kick it into 2nd and again the rpms are up keeping it cool.  If its a hot day you just let off the accelerator and let it drop to the next downshift.  No sense trying to push more heat out of the engjne.  Usually if I lose speed through second down past 27mph Ill just let it coast down to 19mph and kick it jnto first and troll up the hill at 19-20 mph with the engine running against the governor till I get to the top.

1. Get a gun.  Itll tell you all the secrets of your bus, hub temps, brakes, tranny, tstats.  It doesnt lie.

2. Run your bus without adding oil until you get to the low mark.  I used to overfill mine not realizing it.  Once I stopped adding oil it stopped burning oil and now I dont add any but maybe a quart once every 1000 miles.

3. Breaking the ice - Ive learned that there is a magical temp your bus will run fine at (like 190) and once you break that temp you just have a heck of a time losing the heat.  Sometimes its better to just pull off and run the high idle, reset so to speak, let it cool down and then head out again.  Its weird.  Mine will run fine up to 195 but once I break that I just cant get it back down until Im headed downhill again so I try to keep the rpms up once I approach that 195 mark.

4. Hills will play tricks on you.  I remeber heading south out of Denver last year and I was in 4th gear pulling 58-60 mph and rpms were right where they should be and it kept getting hot.  Couldnt figure it out.  It seemed like we were on the flats but it was a slight incline over 15-20 miles and the heat just caught up to us.

5.  Altitude, like the guys said earlier... when you start getting up to 5000-6000 feet your bus is gonna do weird things like smoke and run hot.  Lack of air will do that.  Those are issues I have...  not enough air intake.

Have a good trip.

-Sean
Title: Re: Weird heat issue
Post by: Lin on June 06, 2016, 10:35:45 PM
As mentioned, make sure your gauge is accurate.  Both the sensor and gauge itself could have problems.  Also make sure the gauge is well grounded. 
Title: Re: Weird heat issue
Post by: DMoedave on June 07, 2016, 08:25:39 AM
I have a small level next to the driver window to help me with the inclines. sometimes you think your going level but your not!! it helps me.
Title: Re: Weird heat issue
Post by: Cary and Don on June 07, 2016, 09:31:24 AM
On the determining the grade. Going into Las Vegas didn't look all that steep. But the Eagle got slower and slower. That was a very long grade and it caught up with us pretty fast and it goes on for miles. It also started at some altitude.

We use the GPS to keep track of climbs and speed. The GPS really tells us how fast we were climbing. We watch the GPS for altitude. Usually you start a climb before you realize it. Then you are playing catch up. We use the misters on and off over most of it if the temps start to rise. It's just easier on the engine.

We did Hwy50 through Nevada to Utah. Those climbs didn't look like that much, like from 5000 feet to 6000. But starting out that high made the climb a lot harder. That 1000 feet of climb at sea level is nothing for the Eagle. The ones starting at 6000 feet and going to 7500 feet were even slower.

Welcome to the West. LOL
Title: Re: Weird heat issue
Post by: luvrbus on June 07, 2016, 09:36:01 AM
One great thing about owning a Eagle the radiators are so easy to upgrade where they can handle the heat then you don't need the misters
Title: Re: Weird heat issue
Post by: chessie4905 on June 07, 2016, 10:16:04 AM
#1. Buy a surplus altimeter or set your GPS in the corner setting to altitude if it is available on yours.
#2  INSTALL MISTERS!!!!! Sure, a good cooling system doesn't need them, etc,etc....but they are easily installed and are inexpensive and can save an engine or cracked heads in those occasional times like you are experiencing, which is common with two cycle owners, especially in GMC's, most of which have been upgraded for more power. Diesels, especially two cycle Detroit's are NOT tolerant of overheating. Many times the damage doesn't show up till a couple hundred miles later, depending on how severe.
Title: Re: Weird heat issue
Post by: eagle19952 on June 07, 2016, 10:53:52 AM
still ignoring the shutdown system ?

cheap way to save $30,000.00.
Title: Re: Weird heat issue
Post by: edvanland on June 11, 2016, 06:12:36 PM
I am having the same problem on my MCI 7 and I have done way more than you to try to keep it cool. By the way my misters are made using drip irrigation 1/2" tubing with 180 degree nozzles it works really well. I am going to check on a turbo muffler for mine as suggested, see if that helps. Good luck I live in central AZ and any time I leave home I have form a 7 mile 6 percent grade to a 17 mile, if I am really daring and going east I have about a 40mile one, I don't go that way. Good luck and welcome to the high county and over 100 degree heat on a cool day.