Fluctuating Oil Pressure on a 912
in General Tech Discussion
10 years ago
This has been discussed many times and I've read many of the posts, but I'll have another go.
My 912 (500 hours on it) shows good oil pressure when first started (middle of the green arc). After flying for 15 minutes or so, the oil pressure starts to fluctuate and then drops to the top of the red arc. If I drop the RPM below 4,000 the oil pressure steadies again in the middle of the green arc. Increasing the RPM starts the fluctuation again. This much is repeatable.
The previous owner fitted a dedicated ground from the sensor onto the gearbox housing. Would it be better to ground directly to the battery?
I intend to upgrade the pressure relief spring/piston, etc. at the next annual in a couple of weeks anyway.
I may also replace the sensor at the same time.
If none of the above fixes the problem, where in the engine should I next look?
My 912 (500 hours on it) shows good oil pressure when first started (middle of the green arc). After flying for 15 minutes or so, the oil pressure starts to fluctuate and then drops to the top of the red arc. If I drop the RPM below 4,000 the oil pressure steadies again in the middle of the green arc. Increasing the RPM starts the fluctuation again. This much is repeatable.
The previous owner fitted a dedicated ground from the sensor onto the gearbox housing. Would it be better to ground directly to the battery?
I intend to upgrade the pressure relief spring/piston, etc. at the next annual in a couple of weeks anyway.
I may also replace the sensor at the same time.
If none of the above fixes the problem, where in the engine should I next look?
