RAM916

I have replaced the thermostat on my 3.0L S2 but it is still overheating after about 3 miles. the hose to the new thermo is hot, and when i bleed the fluid is moving... seems bled; but sure enough after a few miles it boils over and I have to bleed all over again. Scratching my head... just noticed that when it overheats, the heat comes through the vents even though heat is off (yes I turn on max heat to bleed). So, heater valve sucking air? is there some magic to bleeding I'm not aware of?? Perplexed and frustrated...

pettybird

it takes a while. I let my S idle for more than an hour before it behaved. leave the bleed screw open on the outlet pipe and wait until it stop sputtering.

John_AZ

I replaced the thermofan switch on radiator. (match temp to thermostat you use).

GL
John

HJK

Assuming you dont have other issues, its a question of patience, they take time to get rid of the air as mentioned above. Frustrating process really, especially when in a hurry (like on track).
H

J Berk

Assuming you get rid of the air and its still hot....how old is the waterpump ?

last year, on the way back from the Hershey swap meet my car big-time overheated....was forced to travel at high rates of speed to keep engine temp down

It turned out that my car had one of the 'cheap' waterpumps with the plastic impellers. About 90% of the vanes on the impeller were gone so it was not moving much water.

Splurged for the OEM / 'spensive' waterpump with the metal vanes and she runs cool as a cucumber in july !

944Ross

I like the idea someone on here mentioned, get the cooling system pressure tester from AutoZone and pump up the system (cold) open the bleeder, while on as steep a slope (front up) as you can find.

North Coast Cab

Jack up the front, helps get the air out of the back of the head.

Jfrahm

What are the symptoms going back before the thermostat replacement? It sounds like you had an overheating problem and replaced the thermostat to no avail? I doubt you had a normal healthy car, the thermostat failed and then after replacing the thermostat you still have problems due to air in the system. More likely you have a spun waterpump impeller, fan or temp switch problem, or something like that.

The cooling system pressure cap can also fail but that does not usually cause overheating. the waterpump impeller is more likely.

-Joel.

dillon410021

lol