A few times in the last 20 hours, during taxi out on the first flight of the day, my oil pressure has spiked briefly over redline. If I pull the throttle all the way back it goes below redline and if I wait a few minutes all will be fine again including runup and throughout the flight.
Troubleshooting guides point to wrong grade of oil for the temps or a stuck vernatherm. This has happened with OATs in the mid 40s to low 60s. Oil is Aeroshell W-100, with Camguard added so it shouldn't be that. I pulled the vernatherm and all looks clean, the ball and seat are smooth. I put a copper wire down the oil channel to the sump, there didn't seem to be any obstructions, comes out clean with no gunk on it. Last oil change I checked the sump screen which was clean, as was the oil filter.
The only oddity I can find is that the vernatherm spring has a flat worn on one coil, see picture. Also looking into the body of the Vernatherm, there does seem to be some wear in a spring coil pattern.
My questions are, could that flat and coil wear be indicative? Seems like that wouldn't do it but what do I know. Also if my oil pressure spiked that much (143PSI) for a short period could it cause damage I don't know about? I've had the cowl off since and there are no blown seals or anything as far as I can tell. Other than this it continues to run like a top. This is a Lycoming O-360-A1A with C/S prop.
Troubleshooting guides point to wrong grade of oil for the temps or a stuck vernatherm. This has happened with OATs in the mid 40s to low 60s. Oil is Aeroshell W-100, with Camguard added so it shouldn't be that. I pulled the vernatherm and all looks clean, the ball and seat are smooth. I put a copper wire down the oil channel to the sump, there didn't seem to be any obstructions, comes out clean with no gunk on it. Last oil change I checked the sump screen which was clean, as was the oil filter.
The only oddity I can find is that the vernatherm spring has a flat worn on one coil, see picture. Also looking into the body of the Vernatherm, there does seem to be some wear in a spring coil pattern.
My questions are, could that flat and coil wear be indicative? Seems like that wouldn't do it but what do I know. Also if my oil pressure spiked that much (143PSI) for a short period could it cause damage I don't know about? I've had the cowl off since and there are no blown seals or anything as far as I can tell. Other than this it continues to run like a top. This is a Lycoming O-360-A1A with C/S prop.
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