I don't recall on the 1955 model, but on the older models, you don't take the housing off the block. There is a set screw/jam nut that holds the pump in the housing. Remove the screw, then slide the pump out of the housing. The set screw engages with a depression in the pump to hold the pump in place, so you have to loosen the screw quite a bit. When you re-install the pump, make sure the recess is in the correct position to engage the screw, otherwise the pump may loosen in the housing and move sufficiently to disengage from the distributor. If that happens, the engine will keep running, but you will lose oil pressure; devastation may follow shortly.
Harvester
