Hello, the engine form the 490 get hot, after 5 minutes. I make an new cylinder head gasket, the cylinderhead is ground, i searched for cracks, but the engine get hot. i dont know if the centrifugal pump works fine? Can anybody help me? I`m form Germany. My english isn`t perfect, but I hope you understand what I mean.

Look in the radiator with the engine running to see if you can see any flow. It may be difficult to see well enough to verify flow. Alternately you can put a short section of clear plastic or glass pipe between the engine and radiator inlet. That should give a better indication of flow. If no or low flow then the water pump should be removed for inspection. You can also look for a steady stream of bubbles from either exhaust gas getting into the coolant or air being drawn in past the water pump shaft or a connection.

If there is good flow then the radiator is the prime suspect. You can flush it out by flowing clean water from outlet to inlet. Note any particles that come out.

Engine timing can also be a cause of heating.

Thanks, i will test it.

HOLZWILLY..................you said " I make a new cylinder head gasket ". Are you say that you actually cut the cylinder head gasket out of something and then installed it........?

pray tell what did you make this head gasket out of ???????

mike