nigelspeedy
Well Known Member
When my IO-360 with mechanical fuel injection was new the engine driven pump would put out ~27 psi from idle to take off power with nary a fluctuation. Now three years and 600 hours later the output pressure has steadily dropped to an average of 20 psi and the fluctuations have increased to as much as a 5 psi drops in the cruise. The drops down to 15 psi could be felt as slight misses or a loss of power. Putting the electrical pump would return the fuel pressure to 28 psi. The interesting thing is that it has happened very slowly so there was no real obvious change in pump performance. The fuel filter has been cleaned every 100 hours but has only ever had the slightest amount of debris in it. The fuel pressure sender was replaced at around 400 hours, along with the oil pressure sensor when they both became a bit erratic. They were VDO types supplied with early Dynon Skyview systems. I've made no changes to the fuel system since new so I was pretty sure it was the mechanical pump. One thing I have done since new is upload my flights to Savvy Analysis which makes it really easy to compare a recent flight with a very early one and use data to make comparisons rather than having to rely on my frail memory. So $422 later I have a new pump and it puts out a steady 28 psi and all is good in the world of RV again.
So a couple of questions:
1. Are the pumps rebuild-able, I'm thinking a spare would be nice.
2. Are there other failure modes, as opposed to the very slow degradation that I experienced.
Cheers
Nige
So a couple of questions:
1. Are the pumps rebuild-able, I'm thinking a spare would be nice.
2. Are there other failure modes, as opposed to the very slow degradation that I experienced.
Cheers
Nige