Under warrantee, I sent my MT prop back to a factory service center since it was “burping” grease from around the blade seals. Not really bad but enough to put a mist on the windscreen.
While it was off and since my condition inspection is coming due next month, I decided to clean and rotate the plugs, get the engine (IO360 8.5:1) boroscoped, and check the compression.
I have been running both ROP and LOP depending on the altitude. I won’t run LOP unless I’m at least 9,000 feet or more. I also use 2,200 rpm for my cruise speed. Typical TAS ROP (9.5 gal/hr) at 9,500 feet is 163 knots and LOP (7.2 gal/hr) is 158 knots.
At 194 hours, scope was normal wear and everything looked good. Mechanic was impressed at how clean the engine compartment was.
When I stopped by and saw the mechanics note, the compressions listed were 73/73/72/71. At first I thought they were low, but noticed something about an orifice in earlier post (size matters) and if memory is correct, it was 0.049 (something Gil was talking about). I was pleased that they were so close together.
Not having any previous compressions to compare it against since this is the first condition inspection, I’m wondering if the compressions are good, average, or poor?
While it was off and since my condition inspection is coming due next month, I decided to clean and rotate the plugs, get the engine (IO360 8.5:1) boroscoped, and check the compression.
I have been running both ROP and LOP depending on the altitude. I won’t run LOP unless I’m at least 9,000 feet or more. I also use 2,200 rpm for my cruise speed. Typical TAS ROP (9.5 gal/hr) at 9,500 feet is 163 knots and LOP (7.2 gal/hr) is 158 knots.
At 194 hours, scope was normal wear and everything looked good. Mechanic was impressed at how clean the engine compartment was.
When I stopped by and saw the mechanics note, the compressions listed were 73/73/72/71. At first I thought they were low, but noticed something about an orifice in earlier post (size matters) and if memory is correct, it was 0.049 (something Gil was talking about). I was pleased that they were so close together.
Not having any previous compressions to compare it against since this is the first condition inspection, I’m wondering if the compressions are good, average, or poor?
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