Overheating...

[1fast89]

Okay, now that we are getting into the hot part of the year my car is starting to run too hot.... I decided to check the water level. Shut the car off, let it cool down...crank it up with the cap off, and it looks okay. Then, the thermostat opens..... The water level goes down about 3-4 inches, and comes back up, down and up (and overflows at times). I have replaced my t-stat, my water pump and now a new radiator. What gives?? I don't see any water in the oil, no lack of power and the compression check came out good (180-185lbs), so I don't think that it is a blow h.g. Has anyone else ever experienced this?? It does it at various rpms...I set the idle to 750 and it does it... set it at 1000 and it does it....1200 and again!! Can someone give me some ideas of what else to check?? Thanks!!

BTW.. the car has been running hot (220-240 in a matter of 3-5 miles). The car can sit and idle forever with no problems. But, once I put the cap back on and drive it, it gets hot. I have tried a 180*, a 160* and now a 192* t-stat along with a new water pump, and a new radiator. Also, I'm running a MarkVIII fan...

Jim

 

[_jb_]

I had installed the wrong fan in my car. Instead of pulling air through the radiator it was pushing it. Maybe check that about.

 

[HISSIN50]

are you using an aftermarket gauge? i dont think someone could go from having a cold motor to having it runnin at 240* within 3-5 miles.

is the cooling system bled? stat oriented the right way? i might try a new cap, since the cap is what allows the system to keep from boiling over (when running it in the garage with no cap, there is no load on the motor).

good luck.

 

[TRWXXA]

i might try a new cap, since the cap is what allows the system to keep from boiling over (when running it in the garage with no cap, there is no load on the motor).

That's what I would suggest too. I've seen a bad cap lead to overheating problems. It's a cheap fix if it is the problem, and a good thing to replace even if it's not.

 

[Iwant5.0]

It also could be your temp sending unit. Probably not but its something else to check and bleed your cooling system

 

[beaver2489]

make sure your fan is blowing air not pulling, replace thermostat if you haven't yet and your radiator could be clogged. I just had the same problem with my new motor. I replaced the radiator and it stays cool no matter what now.