Flyin Brian
Member
- Joined
- Jun 18, 2011
Ok, here goes. Whenever the weather is warmer than 80 degrees out my car always seems to get up to 200 degrees no matter what. I know 200 is not that hot, my new Tahoe quickly goes to 210 and stays there every time I drive it but it is supposed to. I figure I should be able to get my car to stay closer to 180 if everything is working right. I am starting to suspect the radiator is not flowing as good as it should. I removed the radiator cap and removed fluid until I could see the top of the oil coolers and started it up. When the thermostat opened the water level dropped very quickly but was not exactly blasting back through the tube ends. Once it got hot enough that the thermostat was staying mostly open the water was flowing but not that fast. If I rev the engine it flows out a little better but not exactly blasting through like most people say it should. I guess my question is how good should the water be coming through the tubes when the thermostat opens? Should it immediately start shooting out of all of the visible tubes when the thermostat opens and the level drops??
I will now list my combination, history, and things I have tried that did not work. It will be lengthy but my main question is about the water flow as that is what I am suspecting is the problem.
Combo not listed in my sig.
Motor rebuilt 700 miles ago, ran hot on all previous rebuilds too.
GN1 super extreme front mount. I know that hurts cooling ability.
GN1 2.5" aluminum radiator. Had it for 4 years. Ran antifreeze and water for the first 3 years, switched to RMI 25 a year ago and it seemed to help a lot. Recently put a new bottle of RMI 25 in and it did not make any difference this time. Radiator has never been flushed. There is a small amount of visible corrosion on some of the tube ends near the radiator cap.
Dual SPAL fan setup that comes on at 170. Both fans moving a ton of air.
160 degree thermostat that I have checked several times. It opens fully at 160.
Stock auto store water pump that is 2 years old.
I am running the turbo saver and not using the motor oil cooler in the radiator.
Transmission fluid goes through the radiator first and then through a large external cooler. Transmission fluid temps eventually reach 200 as well. I don't like that either.
I am reading temperature on the power logger as well as a VDO gauge and they both read about the same.
Things I have tried that did not work.
I took the thermostat out last summer. Took longer to warm up but still got to 200.
Completely boxed in radiator. Did not make any difference, not even on the highway.
Removed the seal strip at the top of the firewall to let some heat out. Helped very little.
When I go for a drive I usually start with the AC on and go for a cruise. After the engine gets good and warm and the oil pressure drops to 20 at idle in drive I know everything is hot. Then the temp just starts creeping up until it gets to 200 to 205 and the trans fluid eventually reaches 200 as well. I am reading the trans fluid temp in the pan. My drives consist of both traffic and highway cruises. When everything is at 200 I turn the AC off and sometimes crank up the heater to try and help bring the temps down. I start heading home and taking it easy on the throttle. 10 minutes later I am home and the temp may have come down to 195 or 190 if it is not too hot outside (90). When I get home I open the hood and let it idle for a while. Fans run continuously and the car does not cool down much more until I turn it off. Top radiator hose is pressurized and stays that way for a long time after shutting off.
It seems like this car has always run hot. It ran hot with the stock radiator, stock fan, SLIC, and my first motor. I put in a new stock type radiator from Postons and that seemed to help a lot. I switched to the large FMIC, aluminum radiator, and dual fan setup at the same time but it still ran a little hot. I can't remember how hot as that was 4 years ago and I had less instrumentation back then.
I am thinking my next step is to remove the radiator and do a thorough cleaning and back flush to see if any crud comes out. Maybe borrow an inspection camera so I can look at the tube ends on the thermostat end of the radiator and see if there is any corrosion or blockage. Next I may consider a better water pump but historically whenever I had a car running hot and I put on a trick aluminum water pump it made no difference. I could go with a different radiator as well I guess if that would help. I would like to keep the FMIC as it works really well and I don't want to switch back.
Sorry for the length of this post but I just want to be able to cruise around on a hot summer day with the AC on and keep my temps closer to 180. I think this is possible?
Thanks.
I will now list my combination, history, and things I have tried that did not work. It will be lengthy but my main question is about the water flow as that is what I am suspecting is the problem.
Combo not listed in my sig.
Motor rebuilt 700 miles ago, ran hot on all previous rebuilds too.
GN1 super extreme front mount. I know that hurts cooling ability.
GN1 2.5" aluminum radiator. Had it for 4 years. Ran antifreeze and water for the first 3 years, switched to RMI 25 a year ago and it seemed to help a lot. Recently put a new bottle of RMI 25 in and it did not make any difference this time. Radiator has never been flushed. There is a small amount of visible corrosion on some of the tube ends near the radiator cap.
Dual SPAL fan setup that comes on at 170. Both fans moving a ton of air.
160 degree thermostat that I have checked several times. It opens fully at 160.
Stock auto store water pump that is 2 years old.
I am running the turbo saver and not using the motor oil cooler in the radiator.
Transmission fluid goes through the radiator first and then through a large external cooler. Transmission fluid temps eventually reach 200 as well. I don't like that either.
I am reading temperature on the power logger as well as a VDO gauge and they both read about the same.
Things I have tried that did not work.
I took the thermostat out last summer. Took longer to warm up but still got to 200.
Completely boxed in radiator. Did not make any difference, not even on the highway.
Removed the seal strip at the top of the firewall to let some heat out. Helped very little.
When I go for a drive I usually start with the AC on and go for a cruise. After the engine gets good and warm and the oil pressure drops to 20 at idle in drive I know everything is hot. Then the temp just starts creeping up until it gets to 200 to 205 and the trans fluid eventually reaches 200 as well. I am reading the trans fluid temp in the pan. My drives consist of both traffic and highway cruises. When everything is at 200 I turn the AC off and sometimes crank up the heater to try and help bring the temps down. I start heading home and taking it easy on the throttle. 10 minutes later I am home and the temp may have come down to 195 or 190 if it is not too hot outside (90). When I get home I open the hood and let it idle for a while. Fans run continuously and the car does not cool down much more until I turn it off. Top radiator hose is pressurized and stays that way for a long time after shutting off.
It seems like this car has always run hot. It ran hot with the stock radiator, stock fan, SLIC, and my first motor. I put in a new stock type radiator from Postons and that seemed to help a lot. I switched to the large FMIC, aluminum radiator, and dual fan setup at the same time but it still ran a little hot. I can't remember how hot as that was 4 years ago and I had less instrumentation back then.
I am thinking my next step is to remove the radiator and do a thorough cleaning and back flush to see if any crud comes out. Maybe borrow an inspection camera so I can look at the tube ends on the thermostat end of the radiator and see if there is any corrosion or blockage. Next I may consider a better water pump but historically whenever I had a car running hot and I put on a trick aluminum water pump it made no difference. I could go with a different radiator as well I guess if that would help. I would like to keep the FMIC as it works really well and I don't want to switch back.
Sorry for the length of this post but I just want to be able to cruise around on a hot summer day with the AC on and keep my temps closer to 180. I think this is possible?
Thanks.