Is the end of the waterpump shaft designed to cont
yes, the model A water pump shaft is designed to make contact with the cylinder head. That is what controls the end play on a model A pump. If you are using a collar on the pump shaft in front of the snout of the pump, contact with the head is not necessary. I prefer the simplicity of the original set up with the boss in the head controlling the end play. Or, if you are using one of the modern ball bearing pumps that has the shaft staked in the front bearing, contact is not necessary.