engine temps slowly climb and climb and climb

[mywhite89]

After doing all the engine work to the car we have a engine cooling problem. Cooling fans kick on when I see around 198f at the housing. The longer you drive whether you drive nice or not the engine temps keep climbing past M. After it gets that hot I see 215-220f at the t-stat housing. Run the heater on high when it gets their and that helps contain it.

Initially today, it seemed as though my problem was with the cooling system building pressure because I took the cap off when hot and there was no pressure. I elevated the front of the car and made sure any possible air pocket at left the system. Drove the car, still getting hot and now it does have good pressure when I released the cap a bit. No air that I could hear escape just fluid.

I'm letting the car cool and I'm going to pull the 180F t-stat to test it. I have a new 180 to go in. I have tested both coolant sensors and replaced the dummy gauge one, they are both fine and prove similar temps that I see at the housing.

What do you think we have going on? I'm pretty sure I installed correctly, springs go toward the engine. Kind of acts like the stat opens but not all the way. Hope I can find it, otherwise we race one at a time and let it cool for a bit.

Chris

[XR7 Dave]

Make sure that you have a high flow 180 deg thermostat and confirm that it works.

Your FMIC is blocking a lot of air. Make sure you have enough airflow. Do you have dual fans?

Make sure you have no air pockets. Jacking the front of the car up is not the way to do this. Install a lever release 13lb radiator cap. Then cycle the motor warm, then lift the lever to allow air to escape into the overflow. Allow engine to cool and draw fluid back into the motor. Do this until no air bubbles come up in the overflow.

[mywhite89]

Originally Posted by XR7 Dave

Make sure that you have a high flow 180 deg thermostat and confirm that it works.

Your FMIC is blocking a lot of air. Make sure you have enough airflow. Do you have dual fans?

Make sure you have no air pockets. Jacking the front of the car up is not the way to do this. Install a lever release 13lb radiator cap. Then cycle the motor warm, then lift the lever to allow air to escape into the overflow. Allow engine to cool and draw fluid back into the motor. Do this until no air bubbles come up in the overflow.

Car has fan in front of radiator and another on the engine side of fmic. It used to have 2 fans fmic. I removed 1 fan along with removing 1 air restricting trans cooler and the ac condensor, decided that would even things out. This radiator is much better and has less restriction than the setup on my 89 car, not saying that solves my problem....

I got another 180 t-stat from napa which I compared with the old one. Both work the same. Not sure what a high flow 180 degree stat is, maybe thats what I have??? Here's a picture of what I have, heated up and open. Noticed some movement at 185-190 degrees

[mywhite89]

Ok, I looked up a high flow t-stat. Guess I need to find one tomorrow, but I didn't have the problem before with a regular so Im assuming I am fighting an air pocket in the system.

Dave what you are saying is I need to do several heat up and cool down cycles with the car level and see what happens? The radiator I have is aftermarket, hopefully I can find a cap to fit it. Just a stupid question, does this happen to you a lot on these cars? I havent ever had the problem on my 89 and I've had that system open more times than I care to think about.

Chris

[rzimmerl]

You can get a high flow tstat at Advance Auto, Mr. Gasket brand around 10 bucks.

[mywhite89]

Originally Posted by rzimmerl

You can get a high flow tstat at Advance Auto, Mr. Gasket brand around 10 bucks.

Thanks for the heads-up. I'll be grabbing one up today.

Chris

[David Neibert]

Originally Posted by rzimmerl

You can get a high flow tstat at Advance Auto, Mr. Gasket brand around 10 bucks.

That's the same thermostat I'm using. To make bleeding the air a little easier, I drilled a small hole in mine.

David

[mywhite89]

Ok, I drilled a 5/32 hole in the thing and have it back together now. Stuck a little rtv with the gasket, and I'm waiting for it to setup. Cross your fingers and pray for cold engine temps! Most importantly pray that the t-stat didn't slip down on the housing and create more problems!

[TbirdSCFan]

If you have experience underheating in the winter time and no cabin heat, swap out the thermostat for one w/o the bleed hole. Thats why I don't drill any additional holes through the thermostat.

[mywhite89]

Originally Posted by TbirdSCFan

If you have experience underheating in the winter time and no cabin heat, swap out the thermostat for one w/o the bleed hole. Thats why I don't drill any additional holes through the thermostat.

This car is scared of the cold!! lol

T-stat is replaced, car is running. As soon as it started it shredded a rib off the brand new belt. Decided the aluminum tensioner pulley was the problem, now we are back to missing one rib on the belt just the way the car likes it, and an ugly black tensioner is in place, but it does work and doesn't ruin belts.

Takes quite a bit longer but the engine temps still creep up, still working on making sure all the air pockets are gone, not convinced of that quite yet. I believe if this doesn't fix it, I have a restriction in the radiator or not good enough airflow through the radiator when driving, which is tough for me to accept being that I took restrictions off, and before that the car ran cool all the time. Then a again the fans fan all the time before also. He had them on seperate switches, I went back to stock computer control on the fans.

Chris

[TinManSC92]

shredding that one rib off the belt probably has more to do with the power steering pump than the idler pulley. I'll bet you had the p/s pump off and never quite got the power steering pulley perfectly flush with the shaft. Just my 2 cents.

[decipha]

a thermostat usually regulates the temp 15 degrees above rating

a 195 should run about 210

ideally you want at least 200 degrees in the engine, on all out race engines we usually regulate the engine temp around 230 for max power


the stewart/mr gasket tstats are very nice, only thermo's i use highly recommend

don't drill them they already have 3 bypass holes, don't forget to plug the bypass line on the tstat outlet

[jdsgallops]

Slowly building engine temps as you are seeing usually indicate inadaquate cooling capacity. IE plugged radiator, too many tubes removed from the radiator on a previous cleaning, airflow blockage. I would look at the FMIC again and make sure this is not the problem.

[90turbo1]

Originally Posted by jdsgallops

Slowly building engine temps as you are seeing usually indicate inadaquate cooling capacity. IE plugged radiator, too many tubes removed from the radiator on a previous cleaning, airflow blockage. I would look at the FMIC again and make sure this is not the problem.

i agree with this one, sounds to me like the radiator is partially plugged or something like that. everytime I get a car that slowly gets hotter and hotter it is most always the radiator is plugged with sedimate. worth a check or replacement.

also make sure the cap is good and if you can find a higher pressure one try that.

[mywhite89]

Originally Posted by TinManSC92

shredding that one rib off the belt probably has more to do with the power steering pump than the idler pulley. I'll bet you had the p/s pump off and never quite got the power steering pulley perfectly flush with the shaft. Just my 2 cents.

You could be right, this car does have an aluminum p/s pulley. I seem to have bad luck with aluminum pulleys. Squeaking belts or whatever it may be.