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Well, I visited the engine mechanic who wanted to talk with me before we preceded.
First – the flange is indeed not perpendicular to the crank and he will send it out. The crank folks will magnaflux her first to insure there are no cracks, then will chuck her in a lathe and force the flange to be perpendicular by removing metal; I thought there was some heating process and some heavy metal pounding involved, with Wagnerian music playing in the background, but alas, no.
Second, the cam shaft was showing wear – the case-hardening had worn thru on several lobes; correspondingly, several of the lifters show wear along a line across their diameter, indicating they were not rotating .
Third, two bearings in the case had shifted laterally about ¼ inch. Apparently whatever notch and key arrangement there was failed – they need to do some welding of the case so the new bushings will not shift.
So, at this stage, I will have a new lower half. Hold on, I”ll get to the cylinders in a moment.
I asked what caused the lifters to not rotate and he pointed to the laquer – his advice – fly more often to keep water out and rust from forming, and oil film all over everything. He mentioned that modern oils do a good job of retaining the film. He also showed me the case from an engine that come from a flight training outfit. The insides looked as shiny as clean aluminum, while mine looked dark and old, even though the other engine had been flown 100s of hours more than mine. His message was that my engine had sat; maybe I’ll go thru the logs and do a graph of hours per year.
Now to the cylinders: he had not had a chance to give them a good look, but mentioned that I had several options to consider. First he wanted to know how much I flew per year and how long I’d keep the plane. I fly around 50 hours and will probably keep her 5 years. Based on that usage, he suggested one option was that if they were in good shape, he'd do some minor repair, and reuse the cylinders. The other option was to consider more extensive work on the cylinders and then I would have an engine which had a major overhaul, and a more valuable engine. I’ll have to do a bit of math and talking with you all before making that decision.
Well, that’s the latest, and it’s not bad.
Have a great holiday and I’ll see you in Alliance.
First – the flange is indeed not perpendicular to the crank and he will send it out. The crank folks will magnaflux her first to insure there are no cracks, then will chuck her in a lathe and force the flange to be perpendicular by removing metal; I thought there was some heating process and some heavy metal pounding involved, with Wagnerian music playing in the background, but alas, no.
Second, the cam shaft was showing wear – the case-hardening had worn thru on several lobes; correspondingly, several of the lifters show wear along a line across their diameter, indicating they were not rotating .
Third, two bearings in the case had shifted laterally about ¼ inch. Apparently whatever notch and key arrangement there was failed – they need to do some welding of the case so the new bushings will not shift.
So, at this stage, I will have a new lower half. Hold on, I”ll get to the cylinders in a moment.
I asked what caused the lifters to not rotate and he pointed to the laquer – his advice – fly more often to keep water out and rust from forming, and oil film all over everything. He mentioned that modern oils do a good job of retaining the film. He also showed me the case from an engine that come from a flight training outfit. The insides looked as shiny as clean aluminum, while mine looked dark and old, even though the other engine had been flown 100s of hours more than mine. His message was that my engine had sat; maybe I’ll go thru the logs and do a graph of hours per year.
Now to the cylinders: he had not had a chance to give them a good look, but mentioned that I had several options to consider. First he wanted to know how much I flew per year and how long I’d keep the plane. I fly around 50 hours and will probably keep her 5 years. Based on that usage, he suggested one option was that if they were in good shape, he'd do some minor repair, and reuse the cylinders. The other option was to consider more extensive work on the cylinders and then I would have an engine which had a major overhaul, and a more valuable engine. I’ll have to do a bit of math and talking with you all before making that decision.
Well, that’s the latest, and it’s not bad.
Have a great holiday and I’ll see you in Alliance.