Clunking sound, white smoke, overheated engine and coolant

[Jake Raby]

I have two cars here now that have this issue. One has a cracked cylinder, the other a cracked head- both recently had a water pump failure.

If your water pump failed and it was replaced, thats only 1/2 the replacement job. The debris removal from the broken impeller is CRUCIAL as it can circulate through the engine and cooling system. When this happens if debris blocks a cooling capillary inside one of the cylinder heads, the area will gain a hot pot and will crack. This occurs without any symptoms, no overheating and no temp elevation on the gauge.

Was the cooling system cleaned extensively?

These engines NEVER blow head gaskets (never seen a single one) and the heads WILL CRACK before a gasket blows!