Car running Hot

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sixty9xtc

sixty9xtc

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I have been driving my car for a couple weeks now since I got it done. Seem to be running just fine until a couple of days ago. It usually ran about 200 now it seems to be running at 220. I checked the engine at the water neck with a temp gun and it was reading 220 and then I checked the top of the radiator and it was reading 130. I think the thermostat is bad and not opening. Even thou I only have a few hundred miles on the car I would doubt the thermostat is bad. I plan on pulling out the thermostat and boiling it to see what temp it opens and make sure it opens up all the way. Any one have any different advice.

Thanks
 
Before you make any decisions based on the "temp gun" readings, you might want to measure with something else. I assume your "temp gun" is an optical type. They don't directly measure temperature, but rather the emitted infrared light. The reading depend on the emissivity of the surface (black vs white or reflective). A contact type sensor (thermocouple or RTD) would be more accurate, perhaps a cooking thermometer. If the top of the radiator is actually 130 F, you could hold your finger on it for several seconds.

If the temperatures are correct, then no coolant flow, which means either a thermostat stuck-closed or bad water pump. I have heard of water pump impellers coming off or the shaft breaking just before the impellor, though have never seen it. As a young child I recall a highway worker looking in the radiator cap of our 63 Valiant Slant Six which was over-heating and said "no water flow, must be a stuck thermostat", which proved true and he fixed in 5 minutes. I can never see the water flowing, so maybe those old radiators didn't have a baffle at the top.
 
I pulled out the stat and checked it in boiling water and it opened up fine. I got rid of the universal lower radiator hose and found a smooth one that fit with the radiator. Took it out and it still overheats. I guess my next question is how much timing affects how much the engine overheats. I have an MSD mechanical advance distributor with about 45 degrees of advance by 2500 rmp. It ran nice but now i changed out the springs so the total advance doesn't happen till about 4500 rpm. Can having too much timing advance heat up the engine.
 
Tell us everything about your cooling system and take pics if you can.

When exactly is it getting hot? Parked and running? In stop and go traffic? Does it get hot if you are doing a steady 60 mph on the highway?

Telling us that you car gets doesn't give us much to work with.
 
check to see that you have a temp. difference of roughly 30 degrees between the top rad hose and the bottom hose with the thermostat open using your infrared thermometer this will tell you if the radiator is clean and flowing . if you have that temp. drop than chances are you can rule out the rad as being the problem. then you can go to the water pump or check the timing. good luck.
 
Well I found out the shrowd I made was restricting the airflow at highway speeds so it was making the car run how. So i pulled the shrowd off and took off the electric fan and put back on the mechanical fan. Then the car was running great on the highway but running hot in town. So i mounted the electric fan out front and made it into a pusher. Now she runs at 190 all day long without a problem. The next step will be to refabricate the shrowd possibly put on a clutch for the fan to free up a little more horsepower.
 
Is there a reason why you have to fabricate a shroud and not use a stock one?
 
sixty9xtc said:
I pulled out the stat and checked it in boiling water and it opened up fine. I got rid of the universal lower radiator hose and found a smooth one that fit with the radiator. Took it out and it still overheats. I guess my next question is how much timing affects how much the engine overheats. I have an MSD mechanical advance distributor with about 45 degrees of advance by 2500 rmp. It ran nice but now i changed out the springs so the total advance doesn't happen till about 4500 rpm. Can having too much timing advance heat up the engine.
Click to expand...
All that timing probably has alot to do with it.
 
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