[side241]

Hi,

I just yesterday got the plane out of annual, and installed new insulated fuel line on rear engine. Only one flight, but the rear engine did NOT ellicit the problem, so I am optomistic and will report at a later date if it solved the problem. BTW, during this past winter I noticed that the problem occurs much less frequently, but now that things have warmed up it is as frequent as last summer. Also, at higher altitudes (above 15,000 ft) the problem ocurred often. This again concurrs with my theory that the hot engine causes the fuel to vaporize in the higher (less gravity flow), slightly warmer (less air flow), and longer fuel line.

I have never had a problem with the front engine, and it doesn't make sense given my theory on the matter. I may be all wet here, I'm not an A&P, but have you tested the elec. fuel pump and especially filter to make sure there is no impediment to flow? Air is about 600 times less dense than avgas, so just because you can blow thru it, obviously the fuel is still impeded. Also, my mechanic told me a story of a fuel flow problem that could not be found, vents seemed fine. But after repair / replacement of the vents, just stabbing at a possible fix, the problem was indeed repaired. I am fairly confident that my theory on the fuel system is correct, especially in light of some of the responses I have received on this thread from people way more knowledgeable than myself. Thus I would recommend going thru your system completely.

These 'Gremlins' are tough to find. Best of luck and safe flying.
Ben