i got it running 2 days ago , and the thermostate wasnt opening at all!! so i took it out, and it will run for a good long while in the morning probly 40 min before it starts over heating,but once it overheats it just keeps getting hotter. it has new radiator and new water pump and its cerculatuing good when i take the cap off!! what can my problem me?

 

It will definitely overheat without a thermostat. It takes a while to get all the coolant up to temp, but once it does it won't stay in the rad long enough to cool off any. Also make sure the fans are working. Are you running water in the cooling system or 50-50 mix of coolant and water? Plain water has a much lower boiling point than antifreeze and will help it to overheat too. Good luck.

 

put a thermostat in there, it should help a little

jesse

 

Do what Scooter said, and put a new cap on the rad. if you havn't already. The pressure in the rad. and the antifreeze is what helps keep the temp. down. Running no thermostat is an old wifes tale and does not work. If the coolant isn't in he rad. long enough how is it going to be cooled down?

 

Do that and make sure the fans are running. Mine was doing the same turned out to be a fan gone bad.

 

Did you bleed the system when you put everything back together?

 

Check your hoses and make sure your water is circulating.
Remember it's reversed cooled.
I had a problem once where the waterpump blade actually spun on the shaft. This was a reconditioned waterpump that I bought from Napa. If that's not the case make sure your fans are properly coming on. Bleed the system as well.

 

Mine did that when I replaced the water pump because I didn't fill up the water pump with coolant before putting the thermostat in it. The waterpump blades were just spinning in the air and not producing any suction to pull the water out of the radiator and into the motor, so be sure its primed correctly.

I'm assuming it wasn't circulating when the thermostat was in.