Overheating Problems Towing Heavy Loads.

[tuckerd1]

Thought you guys might want to know. Check them thermostats.

My truck has been running a little warmer than normal for quite some time now, but it has been tolerable. But, with my 32' horse trailer with 5 horses, it was starting to get scary when pulling long steep grades. Almost peg temp gauge and hi-temp idiot lite would come on. Never boiled over though.

I replaced the fan clutch and radiator but no improvement. Finally got to the thermostat. Bought new one, removed old one and could not believe the difference in the opening size between the two.

The old had an opening about the size of a quarter. The new had an opening almost as big as the thermostat housing. BIG DIFF! Thermostat may have been sticking some also.

I no longer have a cooling problem. Down right cold running now!

 

[david85]

Where did you get your thermostats from? Ford or international are the only ones that are safe for our engines. Autoparts stores will not have something reliable for our trucks.

 

[tuckerd1]

I bought this one at Advance Auto made by Stant. They been in the t'stat business as long as I can remember. They probably make the t'stat for Ford and International.

 

[david85]

A generic thermostat will not work because these engines have an internal bypass. I have't seen what you used, but you might already have one thats "close enough". Keep an eye on it...

 

[OLDBULL8]

I bought this one at Advance Auto made by Stant. They been in the t'stat business as long as I can remember. They probably make the t'stat for Ford and International.

Don't know about that.

Ya Stant makes good t'stat's for gasser's, but diesel's are a little different.
Without comparing the Stant to the IH or Motorcraft how would you know the difference, in fact the new 203* t'stat's are better for these diesel's, they should run 190*-195* for better overall efficiency. If you check the rad temp with a 195* t'stat ,you will see it's only running around 170*-175* on a normal run without load. If you have a Laser temp gun check it out for yourself. The IH and MC have a notch in the regulating plate that allows some circulation when cold to prevent hot spots in the engine, until the temp. reaches 112* then they start to open. Put one in a pan of water with a thermometer and watch it and the temp to start opening and full opening.

Depending on wether you have a cap at 13# or 16# the coolant won't boil til 250* to 270* anyhow. Unless you have a mechanical temp gauge you don't know what the temp really is.

 

[tuckerd1]

I never said I picked up a generic off the shelf t'stat. It was OE replacement for a 7.3 vin m. Double checked this at a couple more locations.

BTW, I checked and Stant supplies both Ford and International Trucks with many of their parts.

 

[towcat]

the one that's OE for our trucks is made by Robertshaw.

 

[icanfixall]

Its just as posted above.... By cheap and thats what you get. I test what I buy (and its always Ford or International stats) in boiling water. When the start to openthe temp is 192 +0 or -7 degrees. Fully open at 212 degrees. This is straight off the pages of my navistar shop manual. They must travle at least .026 for a fully open stat. If the stat you installed has a flat wqsher under it where the copper pellet is then its the wrong type. It can't close off the bypass hole thats drilled in the block under the seated thermostat. They must have the rubber seal around the body also. I cut that off so I have an unrestricted flow to the thermostat opening. Its simple.. Ford or International or nothing else... We do have a member thats running an aftermarket stat now for years without any trouble. Its up to that person to speak out on this. There is no outing on this board... I just feel good running what I have found to work for me. I also know how to make a thermostat to open sooner and to a bigger opening but its kinda complicated to post it here. I will deminstrate it at the ralley.....

 

[oldmisterbill]

I had an aftermarket thermostat in an engine that was installed by the rebuilder-iy got 20 miles and started to over heat.I went back left it with him asked him if he used an oem stat-yupper he said-left the truck with him.I picked it up the next day went from Maine to WV and in the hills cooked the engine.He had left the aftermarket one in-a tow bill and another engine later he was a believer.

 

[tuckerd1]

Everyone to his own opinion. A name on a box is just that. Now who put the part in the box and the name on the box is a different story.

I towed 32' horse trailer loaded over 700 miles last week and the t'stat performed great. No more overheating.

BTW, I got to thinking about when my overheating issues started. It was back in a very busy period and my water pump went bad. I didn't have time to repair it myself. I let the dealership do it. They also put a new t'stat in it.

Do you think they put the wrong one in then? So much for Ford reliability.

 

[icanfixall]

I sure would like to see the thermostat that you installed. Its great you are able to tow now without overheating. Do you have a part number for the Autozone stat and what did they charge you for it.

 

[Dsl_Dog_Treat]

Got one from Napa and haven't had problems with it yet, but is not daily driven anymore.

 

[tuckerd1]

Stant 14399. It was over $20. Looks like the one Ron posted. I was in the parts store last night after something else and checked for a bypass hole which is there.

You remove the rubber seal around the flange before installation.

 

[Diezel_Cowboy]

I'm with tuckerd on this one. I also put the stant in my truck and have had no problems with it. My truck also runs cooler than it did with the old thermostat. It runs down where I think it should run with the new thermostat.

 

[icanfixall]

Ok... Both of those thermostats have the same looks as the factory thermostats. I may go out and buy one just to compare it demensionally to the factory recommended stat. What is the opening temp on these...