LS3 water pump flow diagram
also the 1st start up, how did manage to get water into the engine?, ie the thermostat on the ls3 pump, doesnt let water out untill it warms up enough, so how do you get water in there?
cheers
dave
As long as you dont have a closed heater control valve, coolant will flow through that circuit to fill the motor. But when filling, I left the radiator cap off until the thermostat opened and kept it full.
Note that with an LS motor, the radiator cam will not be the highest point in the system to bleed air out. I had to add an inline radiator cap housing over the top of the radiator. The external tank connected to the heater hose works too.








