Engine: Lycoming IO-360-A3B6D
TTSN: 3,590
TSMOH: 1,325 (new cylinders, new cam, rebuilt lifters, 2001)
At the last oil change we found approximately 1/4 teaspoon full of ferrous metal in the oil filter. Iron in the oil analysis is elevated, at 90 PPM (average was 30).
We are taking it in for a detailed inspection tomorrow to include a borescope and maybe pull off a couple cylinders for inspection of the cam and lifters. At this time, the major possibility is the camshaft or lifters have failed and engine replacement is neccesary.
I have 3 major options, maybe 4.
Lycoming factory overhaul engines have the new roller camshaft. There is a zero chargeback policy on the core engine provided it is not disassembled or damaged.
IO-390 is same price, but needs a new Hartzell "BA" prop, another ten grand, and about 4K in other costs.
Zephyr engine overhaul is 23K. This is reused cylinders and a new cam and lifters. The major risk here is the case or crank will not pass recertification. Per Aircraft Specialties Services, a replacement serviceable crankshaft for an -A3B6D is 8-10K, and a new one is 14K. they can only be turned to .009 undersize, and it was last machined to .003. A replacement crankcase is ~4K. I would be liable for both.
We will know more on Monday, but it looks like an engine replacement. Must have been all that LOP, climbing at 2,700 RPM, and air racing. Wouldnt that be something, 188 MPH on a bad camshaft at gross weight. I should have known better than to cheat the system
All input welcome.
TTSN: 3,590
TSMOH: 1,325 (new cylinders, new cam, rebuilt lifters, 2001)
At the last oil change we found approximately 1/4 teaspoon full of ferrous metal in the oil filter. Iron in the oil analysis is elevated, at 90 PPM (average was 30).
We are taking it in for a detailed inspection tomorrow to include a borescope and maybe pull off a couple cylinders for inspection of the cam and lifters. At this time, the major possibility is the camshaft or lifters have failed and engine replacement is neccesary.
I have 3 major options, maybe 4.
Lycoming factory overhaul engines have the new roller camshaft. There is a zero chargeback policy on the core engine provided it is not disassembled or damaged.
IO-390 is same price, but needs a new Hartzell "BA" prop, another ten grand, and about 4K in other costs.
Zephyr engine overhaul is 23K. This is reused cylinders and a new cam and lifters. The major risk here is the case or crank will not pass recertification. Per Aircraft Specialties Services, a replacement serviceable crankshaft for an -A3B6D is 8-10K, and a new one is 14K. they can only be turned to .009 undersize, and it was last machined to .003. A replacement crankcase is ~4K. I would be liable for both.
We will know more on Monday, but it looks like an engine replacement. Must have been all that LOP, climbing at 2,700 RPM, and air racing. Wouldnt that be something, 188 MPH on a bad camshaft at gross weight. I should have known better than to cheat the system
All input welcome.