Cracked head gasket?????

I wonder is my overheating problem could be due to a cracked/blown head gasket? It has a new 180* thermostat, new radiator cap, new water pump, and new antifreeze. The radiator is unplugged and clean on the inside, yet it wants to get hot running at high rpm. The electric fan moves plenty of air over the radiator. I need opinions and options. thanks

 

Could very well be. I have the same problem right now and the Jeep still runs fine. At idle it doesn't overheat, but when you drive it it gets hot. No oil in water or water in oil, but still a blown head gasket.

 

Are you loosing coolant? If you have a cracked head gasket you would be either in the oil or on the ground. I had a recent problem with loosing coolant via the overflow even with a new thermostat and having the radiator rodded. I drilled a hole in the thermostat per the threads here and the problem has gone away.

 

Sounds like not enough radiator area to me. How do you know the fan is moving plenty of air?

JB

 

It could be a head gasket and not lose coolant. In my case, I have exhaust coming back in my coolant system and building up pressure in the radiator at higher rpms. I would try everything else first though, but it took me blowing the top out of my radiator before I figured out what my problem was.

 

did you have this problem before or after the electric fan was installed. it could very well be a head gsk problem but befor i condemn it, i would make sure your getting enough cmf thru your radiator. i installed an electric fan on mine and was blowing full speed and moving alot of air, the problem was it was only concentrated on a small portion of the radiator because the fan is too small of a diameter. i went with a larger diameter fan, and so far no overheat yet. (stays pretty cool even with the 304)

 

i'm having a similar problem. overheating at high rpm but fine at idle with my 69 4cyl. i dont see where or how i'm losing coolent but i am. i have installed a new 190 themostat. radiator seems to be fine as well as the amount of air being pulled in by the stock fan. i'm going to install a real temp guage to see some real numbers. does drilling the themostat really work?

 

One other thing I almost forgot about and something you might want to check if you are losing coolant. If it should happen to be a blown head gasket, you might check the exhaust for moisture.

Like it has been said though, it is sometimes best to check everything else before pulling the head.

 

My boy is having similar problems on his Chebby Geo. Water in the exhaust, overheating, water in the oil, etc. We haven't pulled the head yet, but the problem is most likely a blown head gasket or a warped head. If you run the engine with the radiator cap off and can hear gurgling in the radiator, or see bubbles flowing past the opening, it's usually one of the two problems above. My vote would be for the warped head, especially if it's aluminum. To eliminate the thermostat as the source, idle the engine with it removed. Also, if your dipstick looks like it's been dipped in a chocolate milkshake, then you definitely have water in your oil.

tommy b

 

New parts are not always good parts....

Pete