Re: Correct Rebuilt 1972 1972 9.5HP 18-7823 fuel pump
ok.....these can be a real bugger if your not familiar with them.... 1st time i played with one was out on lake, of course in an out of the way cove away from anyone and at the wrong end of the lake.... took me a few hrs of hanging over the back of the boat....cussing... then i gave up and beached her so i could stand in ice cold water and get a better angle on the stuff... that was many yrs ago, and of lil use to you with the exception that it might make you feel better to know that it has happened to someone besides you. To make things worse... it was the fuel line not the fuel pump that day... had a leak and I didn't know any better.
I assume you already understand the principle that the pump works with, but when I have issues with one this is the path i take, works everytime.. I think the process through as far as the fuels pathway through the pump and what must happen to allow it to pump.
The proper orientation of the parts is an absolute must... that said when you look at it, keep in mind that it is a diaphragm pump. the diaphragm moved up and down in relation to the pulses from the crank case. when it moves away from the cavity where the fuel is it makes suction, when it moves towards it there is pressure created. To make it work as a pump a check valve is used on both the intake and outlet of the pump (inside it). one check allows fuel in by releasing when fuel pushes against it while the other is forced closed... then when when the flow attempts to reverse they open and close in the opposite order.
here is a blow up of the fuel pump that i believe you are working with
http://ourimages.co.cc/1977-johnson-9.9-fuel-pump-diagram.html
the pic is of the direct to crankcase version that i think you have.. the link is to the remote version.
If i recall correctly there is either a flapper (gasket type rubber flaps) that controls flow or ball checks... ... with the fuel flow direction in mind... one must be oriented one way while the other the opposite direction.... at that point fuel/air should do what you wish....
Sean
I got to assume there was a small celebration once you got it.