: overheating problem after changing water pump????

10-04-11, 09:19 PM
ok, saturday my low coolant light comes on so i pop the hood and look around, its coming out of the weep hole on the water pump. I get a new pepboys water pump as the one leaking has limited lifetime warranty. only reason I changed it was the leaking weep hole, no other issues.

today i swap it out, fill it up and cant get it to bleed off when cracking the bleeder screw. car started getting hot so i shut it down and checked things, nothing to be found. I got one of those coolant tools to vacuum the system down. several times and still nothing. swaped the thermostat. tried everything again, and nothing. when it gets hot it starts puking it out of the overflow bottle. the hoses get hot but the radiator is cold

"YES" the coupler on the camshaft is attached to the water pump.

since no problems before this im thinking its the new water pump, being pepboys and probably made in mexico, tomorrow im opening both of them and checking to see if its spinning the wrong way.

any ideas

10-04-11, 09:36 PM
Thermostat upside down? Remember, coolant flows backwards in the LT1...

10-04-11, 09:43 PM
the thermostat only goes in one way, if you put it upside down then the housing wont bolt onto the waterpump.

10-04-11, 10:14 PM
Try to burp the system you might have an air pocket, could also be a head gasket

10-04-11, 11:16 PM
i know about air in the system thats why i put that vacuum on the coolant system. I read something that says jack the front of the car up so the radiator is the highest point on the cooling system. then fill it up and run it...

im going to try this first tommorow

"The cooling system on the LT1 tends to trap air when you are attempting to refill it, so there’s a small bleeder screw on the thermostat housing to help vent air. But even this may not be enough, especially on the Camaro. If air gets trapped in the system, the temperature sensor for the cooling fan may not be in contact with the coolant, preventing the fan(s) from coming on, causing the engine to overheat. To get the air out, you may have to raise the front of the vehicle up so the radiator becomes the highest point in the system. Add as much coolant as the system will take, then lower the vehicle, start the engine, let it warm up, then shut it off. After the engine has cooled, recheck the coolant level and add more coolant as needed to top off the system."

10-05-11, 01:37 PM
Good write up. If you want the fans to come on, just put the AC on max, or pull the connector on the water pump. Both actions will make the fans come on, no matter what the sensor says.