n5lp
fugio ergo sum
My airplane has a carburated O-360. Once in a while, in the last few months, there is an issue after the first start of the day. The fuel pressure goes high, around 7 or 8 PSI, and the engine runs very rough at idle. I think it would die, but I can keep it going by leaning to near idle-cut-off.
During and after the run-up things are much better and the engine always runs great at higher power settings. For the rest of the day there is no further problem.
I'm thinking this is a mechanical fuel pump problem but I don't know how the pump regulates pressure. This weekend, at a fly-in breakfast, I asked two different mechanics about the issue and they didn't seem to have any idea.
Do I just need to replace the pump or is there something else I can do? I have checked that the vent line is clear.
During and after the run-up things are much better and the engine always runs great at higher power settings. For the rest of the day there is no further problem.
I'm thinking this is a mechanical fuel pump problem but I don't know how the pump regulates pressure. This weekend, at a fly-in breakfast, I asked two different mechanics about the issue and they didn't seem to have any idea.
Do I just need to replace the pump or is there something else I can do? I have checked that the vent line is clear.