I have two mechanical fuel pumps for BBC. One has a longer arm then the other. I know one is for a sea water pump and the other is block mounted. Would the short arm pump be for the block mounted set up? Or vice a versa? Also is the bottom hose on the pump the inlet or outlet?

Thanks Anthony

I guess your not on the boat today

i don't have the pump that runs off the sea pump in front of me however the block mount pump measures 2 3/8" from the top of the arm where it enters into the housing down to the end of the tip. hope this helps.
john