overheating!!!! HELP!!!!

[69camarokid]

i have a 95 trans am lt1/t56 in a 69 camaro.
I had a blown head gasket. replaced it, head was checked out, all that fun jazz.

Got the whole engine back together this weekend, everything was replaced. I blead all the air out of the engine and have no coolant leaks, the fans work fine, but still i overheat past 250 degrees in just a few minutes time. How can this be. what could be causing this?

Any help or ideas at all would be greatly helpful, thanks

[Vegas69]

Sounds like an air pocket in the engine.....

[69camarokid]

how do i get rid of an air pocket if it is one

[Vegas69]

Take the radiator cap off and put the front tires on some 2x4's. If the temp gauge rises quickly it has to be an air pocket. I'd bring it up to temp with the cap off. Your upper radiator hose should be hot and coolant will be flowing through your radiator. The air pocket will work it's way out the radiator cap fill hole and you should be able to achieve a temp around your t stat. Then top it off and put on your radiator cap.

[Twentyover]

stuck stat?

[69camarokid]

how can i test to see if the thermostat is stuck

[69camarokid]

well, the thermostat seemed to be just fine, but i replaced it just to play it safe. when i took off radiator cap i noticed my radiator was almost empty. I had filled it before i left this morning so my overheating must have been caused by an ampty radiator. so the water/coolant must have leaked out somehow. or so i thought.

So i refilled the radiator, turned on the car, new thermostat and all. it sat ther at idle and within a few minutes it was past 200 and climbing. the 180 thermostat made no difference. I checked under the car.... no leaks of any kinds? the fans run full time. I dont understand how this overheating is happening!!!!

any other ideas?

[tumper93]

LT1's are hard to bleed all the air out unless you can pull a vacuum on the system when it is dry. The way I bleed them before I had the tool was to fill the radiator or surge tank until full, then open the bleeders until coolant comes out, sometimes it won't but the coolant level should drop. Close the bleeders and start the engine then open the bleeder at the water pump and see if any air escapes if only coolant come out, close bleeder, rev the motor to about 2k and even if the temp gets kind of high...say around 240 it will be okay as the bubble should quickly purge. Always seems that it gets kinda warm before it lets go but does do it with RPM up...it won''t if left at an idle.

[69camarokid]

LT1's are hard to bleed all the air out unless you can pull a vacuum on the system when it is dry. The way I bleed them before I had the tool was to fill the radiator or surge tank until full, then open the bleeders until coolant comes out, sometimes it won't but the coolant level should drop. Close the bleeders and start the engine then open the bleeder at the water pump and see if any air escapes if only coolant come out, close bleeder, rev the motor to about 2k and even if the temp gets kind of high...say around 240 it will be okay as the bubble should quickly purge. Always seems that it gets kinda warm before it lets go but does do it with RPM up...it won''t if left at an idle.

tried this, but to no avail. The car still over heats.
dont know what to do. I never had this problem before
Ive heard there is an impellor in the water pump and that if it is lined up incorrectly then it would cause overheating. anyone heard of this or know anything about it?

[67 ls1 vert]

Do you see water rushing by with the cap off the radiator with the water temp up at operating temp? If not, your radiator may need to be repaired.

Also, with the car running and the cap on, wear gloves and try to squeeze the upper hose. You might get the air bubble to dislodge.
Good luck.

[68BNUT]

This may be dumb, but Ive done it before. Did you put the gear drive piece (whatever its called) that drives the water pump back in after you put it all back together? I replaced my water pump and left that on the old one, took me all dang day to figure it out!!

[69camarokid]

so i didnt pull the water pump, but i removed my intake tubing and was able to see down behind the water pump. My shaft is spinning when the car is on. Is it possible that it could be spinning and not work.
OR does the fact that the shaft is spinning mean that my water pump is ok and that it is somehting else?