Temp/Overheat Question
Thread Starter
Intermediate
Joined: May 2013
Posts: 28
Likes: 0
Temp/Overheat Question
Finally got to take the 80 out for a spin Saturday. It was not that hot (for Florida anyway) so we were not running the air. We were cruising at 60-65 for about an hr.
The gauge got up to approx. 220...would slowly climb the longer we drove.
It just did not seem right to us. Rad is flushed, new water pump, shroud and seals all good (seals new) air dam etc etc.
So tonight we shot the temp sensor with our IR gauge. At the sensor it reads 260. On the block it reads 175. Now I know the block is not an extremely accurate reading, but it would seem to me that it is much more accurate than the sensor in the head.
The gauge inside is reading approx 200-210. The car has been at idle now for 40 mins with the ac running.
Thoughts?
The gauge got up to approx. 220...would slowly climb the longer we drove.
It just did not seem right to us. Rad is flushed, new water pump, shroud and seals all good (seals new) air dam etc etc.
So tonight we shot the temp sensor with our IR gauge. At the sensor it reads 260. On the block it reads 175. Now I know the block is not an extremely accurate reading, but it would seem to me that it is much more accurate than the sensor in the head.
The gauge inside is reading approx 200-210. The car has been at idle now for 40 mins with the ac running.
Thoughts?
Burning Brakes
Joined: Apr 2013
Posts: 926
Likes: 2
From: Castle Rock CO
I would say drop a lower temp Thermostat into the water neck to get more water flow past the sensor. More water flow thru the rad the cooler the engine will run. The IR Temp gauge will read temps where you shoot it. The Water Neck on the engine is going to be you hottest point of temps because the water is flowed thru the radiator before it reaches the water neck and that is where the interior temp gauge is reading it from.
My next thought is Did you test the temp of the Radiator? Transmissions will cause the engine to get hot if they have not been serviced in a long time. Why because they use the Radiator to cool the transmission. Now this is just a guess and I would check the temps at the outlet on the water pump to confirm it but if the tranny is getting hot it will heat up the water in the radiator going back into the water neck on the top end of the engine where you got your hottest reading.
You may need to just have a new filter and a flush on your transmission to get the temps down.
The only reason I suggest this is because my tranny is heating up my engine and performing maintenance on the transmission has brought my engine temps down again.
My next thought is Did you test the temp of the Radiator? Transmissions will cause the engine to get hot if they have not been serviced in a long time. Why because they use the Radiator to cool the transmission. Now this is just a guess and I would check the temps at the outlet on the water pump to confirm it but if the tranny is getting hot it will heat up the water in the radiator going back into the water neck on the top end of the engine where you got your hottest reading.
You may need to just have a new filter and a flush on your transmission to get the temps down.
The only reason I suggest this is because my tranny is heating up my engine and performing maintenance on the transmission has brought my engine temps down again.
Last edited by MakoJoe; Jul 23, 2013 at 11:12 PM. Reason: More info
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Whats your timing set at? If its not advancing far enough it will run hot.
A cooler thermostat will not fix it unless the one you have is bad. The T-Stat sets the minimum operating temp. The cooling system isn't keeping up with the heat load so either too much heat going in or not enough cooling capacity (obvious I know).
So is the Air Dam in shape? Is it stable, not moving with the air flow? Sure about the rad to support seals? Tranny slipping? Those are the things that will make it run hot on the highway, might be others.
A cooler thermostat will not fix it unless the one you have is bad. The T-Stat sets the minimum operating temp. The cooling system isn't keeping up with the heat load so either too much heat going in or not enough cooling capacity (obvious I know).
So is the Air Dam in shape? Is it stable, not moving with the air flow? Sure about the rad to support seals? Tranny slipping? Those are the things that will make it run hot on the highway, might be others.
Thread Starter
Intermediate
Joined: May 2013
Posts: 28
Likes: 0
Thanks for the thoughts. Tranny has been done...flushed and new filter prior to this ride.
Yes, the seals are all good. We changed the rad support and replaced all seals at that time.
Timing is one thing that has not been "checked". We did replace the timing chain, and car appears to be running well...But we did not shoot the timing chain which we will do.
Hate to spend useless $$$ on new rad and fan set-up if really not needed. When these cars were built, I am sure they were not built to overheat!
Yes, the seals are all good. We changed the rad support and replaced all seals at that time.
Timing is one thing that has not been "checked". We did replace the timing chain, and car appears to be running well...But we did not shoot the timing chain which we will do.
Hate to spend useless $$$ on new rad and fan set-up if really not needed. When these cars were built, I am sure they were not built to overheat!
Thread Starter
Intermediate
Joined: May 2013
Posts: 28
Likes: 0
Okay...no not loosing coolant. But remember, AC was not running, nor was it a hot day. In fact temps were at 9PM.
Clutch fan is working correctly...that is the only fan on car. I am correct in my understanding that aux electric fan is only with L-82?
Clutch fan is working correctly...that is the only fan on car. I am correct in my understanding that aux electric fan is only with L-82?
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