We tested for combustion gases using the block tester and we got a negative result. we also installed a pressure gauge on the reservoir and the max pressure we got was 3 psi, during a stall test I wouldnt think the cylinder is cracked since the whole engine is new, but anything is possible. Would an air pocket cause this, what is the purpose of the thermal valve on the system?
I think the air pocket is the only that is left if everything else has been replaced. The thermal valve is in-line with the top small radiator hose going to the reservoir and the turbo tee's off from that line after the valve. What effects would bypassing the thermal valve have if any?