6/71 TIA - Starts but do not run..

[Navigat0r]

Long story short ... new to this forum, but know my DD's pretty well, but got stumped this week-end..

Started engines, but failed to remember that I had fuel tank valves switched off .. (Two tanks gravity feed a single 50L clearing tank, with fuel pickups from top... and have water drain point on this).

Of course engines stopped after a short while and I then remembered the fuel valves...

Primed Stb engine, ran her up and all OK .... Port engine however, after primed starts, runs for a couple of minutes, then starves again...(process repeated several times).

Fuel supply line could in theory be de-laminated, but appear to have free flow, from tank to pre-filter, pre-filter to primary on engine, primary to pump, pump to secondary and secondary and through injectors t return lines & tank...

So questions I have are:

1) What's the likelyhood of fuel pump damage (cannot hear anything abnormal from the pump)?
2) Would the engine run for 2 -3 minutes on what was primed, with a faulty fuel pump?

I hope that I have introduced air to the system, but I have failed to find the culprit yet ..., but will run a seperatee fuel supply line (temporary clear plastic hose) to the filtes next WE to test the supply line...

Any other thoughts from the forum on what the cause may be ?

Thanks in advance...

 

[jgmo]

Sure sounds like air to me. I think 0% chance of pump damage but easy enough to check pressure if in doubt. If your alternate fuel line works, then suspect air leak. You can plug the line close to the tank then use regulated air to pressurize with 20 or so psi and spray soap solution to find the hole.
Good luck.

 

[Navigat0r]

Basically a hairline crack in the cannister bowl bolt seal... so although new & replaced, still was faulty and caused the problem after being run dry....

 

[jgmo]

Good onya for finding it. Those kinds little "coinkydinks" would run me in circles when I was wrenching everyday. But it's all part of breaking it down and figureing it out.