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Topic: Overheating 1992 U240 with Cat 3208 (Read 2978 times) previous topic - next topic - Topic derived from 94 8.3 Cummins overhe...

Overheating 1992 U240 with Cat 3208

I also have an overheating problem. I think I have a Cat motor. I have only had this coach about 2 years, and when I purchased it the previous owner had just had a brand new radiator installed, apparently he was also having temp problems and failed to mention it to me.

My problem is it heats up on the slightest uphill grade. We are in AZ, and I have only made one short 400 mile trip with it. Can some of you guys please tell this dumb OLD (84yrs) Cowboy where to start looking for the problem??
Any and all help/suggestions truly appreciated.

Rick

Re: Re: 94 8.3 Cummins overheating

Reply #1 –
We need to know which Cat engine,miles on engine the more info the better we can help,which oil,etc,when filters were changed.
Do you have a infared gun to verify the temps?

Re: Re: 94 8.3 Cummins overheating

Reply #2 –
Quote from: Karl Shurtleff –
It is running well over 210 and confirmed with a laser thermometer. I will look for a more accurate laser as I am not sure of the accuracy of the one that I have.

Boil a thin metal container of water.  Turn off the heat and aim your infrared pyrometer at the side.  If it read 212F you're in the USA, 100C you're in Canada.

Art

Re: Re: 94 8.3 Cummins overheating

Reply #3 –
A leaking head gasket can cause overheating. Easy to check for products of combustion with the radiator cap off. Read here: 8 Essential Cooling System Checks and How to Perform Them

Check the air cleaner. Restricted air cleaner may cause the engine to be overfueled with increased heat.

Marginal cooling will be worse at high altitudes.

Drop a gear and keep RPM up on grades.

Pierce

Re: Re: 94 8.3 Cummins overheating

Reply #4 –
Rick, how about downshifting and going slower up hills. This was our answer to heat gain.

Re: Re: 94 8.3 Cummins overheating

Reply #5 –
Wowwwww, thanks for all the great suggestions. Here is what I know and what I don't know at this point.

HERE IS WHAT I KNOW
The motor is a 3208-T Cat as Mike & Pamela mentioned.
The motor has 182,671 miles on it.
The radiator is in the rear of the coach.
There are two (2) small air scoopes on each side to bring air into the motor compartment but do not know if they are factory installed or add on's.
We took it in to the Napa dealer and had all the filters and fluids changed right when we purchased it.
The radiator was brand new when I purchased the coach.

WHAT I DON'T KNOW
Have not checked to see what the thermostat looks like, and do not know if a new one was installed when the radiator was replaced.
Do not know the temp of the engine, but will by Friday as I have ordered an infared gun and a antifreeze/water coolent hydrometer.
Have not checked the fan belt, the rotation and speed of the fan blade, nor have I checked to see if it is pulling or pushing the air as I read about in another post.

MIKE
What pictures should I take and post?

Thanks again guys for all helpful advice. I was also wondering, should I start a NEW post as have kinda hijacked this one and don't wan to step on any toes !

Rick


Re: Re: 94 8.3 Cummins overheating

Reply #6 –
Quote from: RevRick –
MIKE
What pictures should I take and post?
Rick,

I was just wanting you to post a pic. of the engine if you weren't sure what engine you have. That way we could see, as a pic. is worth like a lot of words. With you knowing it is a 3208 then there is no need to post a pic of the engine.

Mike

Re: Re: 94 8.3 Cummins overheating

Reply #7 –
Oh, got it Mike... Thanks

Re: Overheating 1992 U240 with Cat 3208

Reply #8 –
I have split this topic off, as it is not related to overheating of a Cummins 8.3 with side radiator.

Re: Overheating 1992 U240 with Cat 3208

Reply #9 –
Quote from: wolfe10 –
I have split this topic off, as it is not related to overheating of a Cummins 8.3 with side radiator.

I was worried that might be the case, thanks for the split Brett, I really appreciate it.

Rick

Re: Overheating 1992 U240 with Cat 3208

Reply #10 –
When I worked for Foretravel in Florida we were having overheating issues with the 240 with the 3116 engines. We had to add much belting material around the radiator to make sure that the air didn't bypass the radiator and that seemed to help.

Re: Overheating 1992 U240 with Cat 3208

Reply #11 –
Make sure your rear radiator isn't plugged up. Oil and other liquids (rain off the road, etc.) get pushed into the fins and act like a dirt magnet. My 1981 Foretravel had a 3208 and a rear radiator that was filthy when I bought it. I had problem with heat.
Simple green and a couple hours at the car wash solved the problem and I made a habit of repeating that process on a regular basis.
If you flatten a plastic straw and insert it between your radiator fins you may be surprised at how much crap is in there. Keep washing until it is clean.
I also do this on my 1993 U225's rear radiator.
As for climbing grades, get in the right lane, downshift, put on your flashers and watch your temp gauge.

Re: Overheating 1992 U240 with Cat 3208

Reply #12 –
To be clear, on a rear radiator, it MUST be cleaned from the front.

The front of the CAC is where most of the dirt and debris will be deposited.

Re: Overheating 1992 U240 with Cat 3208

Reply #13 –
The 2 belts that drive the fan can be a little loose and slip enough to result in this symptom.
The  T stat is probably ok as it runs fine until high loading  . 
If there is black smoke at  high power , maybe the fuel pump is turned up for more power and resulting heat .  The pump has a safety wire on it from the factory. Maybe it has been turned up.
If the oe muffler is still there, that will add to the heat.
  I found that the coolant can be low and the temp can creep up.    Top it up , it will overflow until it's at a happy level .
Mine had no recovery bottle but I added one.
The cap should be a 9 or 13  #  . Mine is 9  .
 

Re: Overheating 1992 U240 with Cat 3208

Reply #14 –
You may also remove the rear door and see how much it helps. It drops my temp by 10 f

 Also. , verify that the oe shroud  is intact . It allows the fan to do its job. Slim chance that it was left out when the new rad was te installed.

Re: Overheating 1992 U240 with Cat 3208

Reply #15 –
Boy what a bunch of all great ideas and suggestions. I will take every one of them into account tomorrow when I get back home in the afternoon. Don't mind working outside now that the temperature is going to be back down in the lower 100's. Was 114 outside on the back porch today, in the shade of course!!

Thanks to each and everyone of you.
Rick

Re: Overheating 1992 U240 with Cat 3208

Reply #16 –
Have had pros and cons thruout the years but if everything above is in working order I would change to synthetic oil and see if
that helps,the Amsoil 10w40 does run cooler then dino oil,I have never seen 210 degrees,on some downhills I have seen 180 and below,most of the time we run at 180 degrees,also have it in the hyd system.

Re: Overheating 1992 U240 with Cat 3208

Reply #17 –
Would it be ok to plug in a separate temp gage to double check the one in the dash? Does anyone know where the temperature sender is on my Cat 3208 motor, and the FT part number?

Rick

Re: Overheating 1992 U240 with Cat 3208

Reply #18 –
While I agree that having an accurate temperature gauge would be a good idea.

But, since your gauge shows a temperature rise "on the slightest grade",  you KNOW you have an engine temperature issue/inadequate cooling even though you may not know the exact temperature.

BTW, my suggested absolute first step is to replace the thermostat(s) (Cat calls them regulators) and gasket(s). You could even consider this routing preventive maintenance.

Same for cleaning the front of your CAC, again ASSUMING you have a rear radiator.

Re: Overheating 1992 U240 with Cat 3208

Reply #19 –
Mine does not have a CAC
The 300 should , but with side radiator?
Maybe the build date is late 88.