I have rebuilt exactly "1" of these pumps. It is in my collection of parts yet to be used. What's your question about the pumps and valves?
Info from another person on another site tells me my issue is the valves...
Backstory:
first of all, my car has been off the road since mid 97. Since then I have dismantled the car for a complete resto, not including the engine (yet), which ran up to the day I parked the GT6. I have had the engine and transmission, as a unit (not yet separated) sitting on a test cart, which I started from time to time.
At one point I had trouble with the fuel pump, so I swapped it for the one on my spare block.
When I ran my engine I would have to use the prime lever and starting fluid to get it started, would run it for a little while, then put it to bed till next time.
I now have my chassis rebuilt, tub on the chassis, and engine bolted in place. The car is not yet complete, but I would like to be able to move it around under it's own power. I didn't think much of why the engine only ran for a short time before dying.
Now to the meat of the question: Last week when I was hooking everything up I discovered a leak on the outlet side of the fuel pump. Turns out I had cross-threaded the brass fitting and messed up the threads, so it leaked. This is where the fun started, and why I have 2 different pumps in that photo.
I pulled the pump off so I could swap tops. Sure, I could have done it on the block, but for some reason I removed it from the block. In the end that part proved to be a good thing.
I installed the pump back on the block and primed it, gas flowed but not when cranking, and I realized the lever was not coming in contact with the cam lobe-that would explain why my previous times of running the engine only lasted about 30 seconds or so-long enough for the carbs to run dry.
after struggling mightily trying to get the lever on top of the cam as stated in the manual, I pulled my other pump and compared the two, and discovered the different arms. (turns out my installed and working engine is a KD GT6 engine, and the spare block is an early KC engine). Another swap of tops so I have a good top on the correct base with the curved arm and I got a good fit of the pump. A crank of the engine showed the diaphragm moving up and down now.
At this point I reassembled the pump, ran the prime lever, and got nothing. Over the course of the afternoon I took it apart multiple times and tried multiple things, including breaking out my rebuild kit.
At one point since then I got a little fuel pumping manually into the bowl, but I could see air sucking in around the new glass-to-body rubber seal. After making a new gasket out of cork (as it was originally when I bought the car in 95), I have yet to get it to prime manually or with engine cranking, even with trying the body with the stripped outlet. It's leaking air somewhere.
Now no combination of my two fuel pump parts, gaskets, and old or new diaphragms work anymore, when just the day before they were working fine. (aside from the lever bit)
So the question now is
1) Am I missing something simple?
or 2)are my check valves indeed shot and leaking air? if so, anyone have any experience replacing them?
(my question about the glass stems from my son being curious and accidentally breaking my spare. I'd like another)
Sorry for going on and on...but there you go.