Ls1 c5 Vette won’t cool
Thread Starter
Staging Lane
Joined: Jul 2016
Posts: 52
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Ls1 c5 Vette won’t cool just Put a new engine in a c5 and can’t get it to cool. New thermostat and housing. Originally I bled it and started it up. Engine temp went to 220 but all the lines were cold. I took the top line off of the water pump and nothing came out. As it was still running I took the coolant cap off and coolant started coming out of the top of the water pump. So I bled the system again keeping the cap off. All the lines were hot. Heater core was getting heat and working. Top hose was hot. Bottom hose was hot but temps kept climbing. Put the cap on and Turned on the fans and still climbing 220+. So it seems to be fine with the cap off. As soon as I put the cap on it pressurized the system and does not want to cool. Any tips ?
