Hey guys, I just picked up an 89 wagon, it had a frozen alternator and cracked radiator. I fixed the alternator and changed out the radiator, hoses and thermostat. I did a compression check (all good) and bled that radiator according to Chilton manual. Checked the fan and it is working properly.

The problem I am having is it will sometimes run very hot to the point of overheating. I only notice it when the car is going up an incline or driving on the freeway over 55mph. When I am on the freeway, it doesn't start overheating for a good 30 miles, when I notice that the temp gauge started to rapidly rise I started to pull over, but noticed that when I was less than 55mph the temp goes down. So I drove it farther, it didn't start going up again till about 5 miles from my house. I did the same thing, I put it on neutral and coasted for about 1/8th mile, then the temp went down. I finally get off the freeway and went through stop and go traffic, and the temp never went up.

So I was wondering if anyone can suggest a reason for this, a solution or something I can do to fix it.

Thanks for all your inputs!

 

Thermostat bad? If its not opening it will overheat after a while.

 

Brand new thermostat! I also picked up the 180 degrees one instead of the 195.

 

Are you getting any white smoke out of the exhaust? Open the radiator and see if their are any bubbles coming out of the radiator. If their is either of these, then your head gasket is gone and the only way to fix it is to pull the head and replace it.

 

no big plooms of smoke from the tail pipe, and no bubbling from the radiator. I am not losing oil either or coolant.

If the water pump was bad, would it cause it to run hot??

 

Yes, bad water pump would make it hot, that could be it. Fins of pump wear over time and stop pumping well.