1990 over heating-best approach

[jjohn]

The young guy I sold my 90 to called me yesterday asking about over heating. It always ran on the hot side in the summer heat, but I never towed much with it and it was never limiting to my use. He has on the other hand put a 2000 LB popup camper on it and has overheating issues on 70 degree days on Colorado mountain passes. I’m thinking he should just upgrade the radiator to a cross flow type. He is in a hurry as he is suppose to leave on a trip in four days. What do you think guys doable? what would it take? He is a nice kid, I would like to help him out.

 

[Gary - K7GLD]

Adapt and swap in a '93 radiator - runs about $300 in parts...

 

[jjohn]

Gary

Thanks Gary do you have a parts list from your converstion. . tips maybe? am I on track with the following, 93 radiator, 93 upper hose, 93 shroud modified to 90 fan in some way am I missing anything.

 

[AlK]

Just a thought - is the thermostat opening all the way or is it stuck?

 

[jjohn]

Alk

Thanks, I asked him that also, he said he tried running it without the thermostat and I believe a new one also. 70 degrees, 2000lbs and a mountain pass doesn't seem like enough to hit an extreme like this 90 degrees maybe.

 

[KEENO]

search is back....

Hey Jim!



I can't seem to find the exact posting that I went in search of... ... You know - The one with part numbers!



How about these:



Radiator info



more Radiator stuff



some more Radiator stuff



still some more Radiator stuff



I hope this helps... .



KEENO (The guy w/ the really cool expandable camper)

 

[rwinslow]

1990 Overheating

Some more ideas - I had an overheating problem on my early 91 a couple of years ago and correcteded it perfroming the following:



1) Cummins / Fleetguard used to sell a coolant additive that cleaned the radiator and engine of soft deposits, it worked very well and was safe for the engine and radiator. Refill with Fleetguard anti-freeze and distilled water or use the Fleetguard pre-mix.



2) Remember that heat transfer capabilities of ethylene glycol and water mixture drop off significantly if there is more than 50% ethylene glycol in the mix.



3) Clean the bugs, dust, and dirt out of the radiator fins.



4) If memory serves me correct, operation without a thermostat can lead to overheating due to recirculation problems.



5) Use a Cummins or Chrysler thermostat. I had used a NAPA 'direct replacement' thermostat and it resulted in overheating.



6) If the truck is a 5 speed, run the pass in 4th gear - this will keep the water pump RPM's up and lower EGT's and water temperature.



7) Check that the idler pulley is providing adeqate tension and that the belt is not glazed or slipping.



I now regularly tow 8,000 lb loads with 1,500 lbs in the bed over 10% grade, 10,000 foot passes at 85 F without any overheating problems.

 

[jjohn]

Thanks Guys

Really Kool Keeno, I searched on everything but radiator. . Duh.



rwinslow, Good tips to check I have been passing on this info to his answering machine I hope he is getting them. By the way Cummins Rocky mountain did a cooling system clean out - power flush to this truck right before I sold it to this guy.

 

[jjohn]

Thought you guys might like to know

Thought you guys might like to know what the problem ended up being... Bad head gasket was heating up water? There is a lot more to this story and Cummins Rocky Mountain took care of this guy and his new wife. Big time!