Hey, everyone I have a 72 FJ40 stock motor in it. H e i distributor i'm overheating out of nowwhwre... My radiator is 20° difference between enfeed out feed tested thermostat tested interior gauge flushed radiator found a plugged water jacket in the back with the drain I fixed that I do have a flex fan with a shroud. I'm still overheating. What else can it be? My timing is good at about 15° before top dead center..... Infrared heat gun shows about 170 all the way down the head.But my internal gauge is showing 230.... What else can I check and how
Another overheating post
- Thread starter Crusher 72
- Start date
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Your stock gauge can be off/not accurate. Take your IR gun & measure top of radiator & the bottom also. Measure the radiator fins & along both sides of the head on the engine.
You’ve got to get accurate information & your stock gauge might not be giving it to you.
You’ve got to get accurate information & your stock gauge might not be giving it to you.
- Thread starter
- #3
Hey John, thanks for the reply. I have a stock and an aftermarket gauge. I've put the negative to the motor and the gauge bottoms out. So I think my gauge is good.
The ir gun from the top of the radiator to the bottom shows twenty degrees difference , which I think is normal
- Thread starter
- #4
Should The head read the same as the Gage inside.When you're reading the head with an I r gun
Measure the top of the thermostat housing. It should be close to the rating of the thermostat, 180* or so.
Is it boiling over or just the gauge says its running hot? Do you run window screen in front of the radiator? It will keep bugs from blocking the air passages. Do a compression test to make sure the head gasket is still good.
Trust your IR temperatures from your IR gun…do not trust stock dash gauges.
Warm your engine up & post temps from your T Stat housing…using your IR gun.
Warm your engine up & post temps from your T Stat housing…using your IR gun.
- Thread starter
- #8
T stat is 142.....top rad.hose 130...bottom hose 110.....gauge reads 245.....when I ground the gauge out it bottoms out 260plus.....the gauge rises slowly....tested temp sensor resistance and it chamged with heat and cold....so temp sensor bad?