Tahiti Trip:
Engine update: Success! But not only because of the refurbished fuel injector pump. It was a combination of four problems.
1) The fuel injector pump: After refurbishing, I reinstalled the pump (see Removing the Injector Pump), bled the engine, same symptoms! Arghhh! So I did the whole gravity-feed-fuel directly to the injector pump intake technique (see Bleeding the Bleedin’ Perkins under “Troubleshooting”) and the engine ran perfectly! First time in 3 weeks. So that was something.
2) Racor Fuel Filter: Whenever I would change a fuel hose while troubleshooting, the fuel would drain out of the Racor filter. I then noticed it would drain back to the fuel tank even with all hoses connected and tight. If you take the top of the Racor off and fill it with clean fuel, it should NOT drain back. Hmmm. I disassembled it to find a steel ball sitting on a gasket. This check-valve is supposed to prevent drainage, but it had a string of algae sitting between the ball and the gasket. Normally this wouldn’t affect anything, but in combination with problem 3), it did!
3) A small crack in the fuel return line fitting at the top of the secondary fuel filter on the engine: This crack also would not prevent the engine from running, but in combination with 2), it did! The Racor’s fuel would try to drain to the tank because of the failed check-valve and create a small amount of suction. The suction was then allowing air to come in through the cracked fuel line fitting, introducing bubbles every time the engine shut down.
What’s wrong with this picture? The filter in the background has an extra gasket blocking the fuel flow! The bottom cap in the foreground is good.
4) Secondary fuel filter: This was the main problem. I replaced the old filter (Fram 1191A) with a different brand (Napa 3166). The new Napa filter had flow holes in a different configuration than the Fram. I replaced the gasket such that it blocked those holes created a fuel restriction. Whoops.
Well, I learned a lot about my fuel system at least. And now she starts with just a tap from the starter and runs like a dream!