The last otherwise good run ended with a bit of overheat to about 230-240F, engine ran good and shut down normally. On the next start it fired but would not keep going past a few seconds. This same behavior repeated on each of maybe half a dozen subsequent attempts. Doubt very much if OH has anything to do with it.
Symptoms. Before, when I primed with hand plunger on the lift-pump I could feel pressure building and eventually releasing accompanied by the hissing sound of what I would call bypass but I don't think it was the relief return valve cycling. I could also see fuel moving in step with the prime pump strokes in the transparent lines connecting the fuel tank and pump and filter.
Since the failure I no longer feel any relief, hear it, or see fuel moving except a very tiny bit. If I prime enough the engine will fire but will eventually die, even if I try to keep hand priming. It 'seems' as if some anomally is preventing fuel from getting into or through the pump back to the tank.
I have changed the relief valve and think that a double failure in sequence (the old valve and then the new one also) would be very unlikely though not impossible.
Having just removed the pump I'm looking for an easy fix OR it goes to the shop for a rebuild (but not the same shop that built it about 3 years or that many hundreds of hours ago.
