Os GGT 15 crankpin hardening
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Os GGT 15 crankpin hardening
Hi all experts
I am having problems with the crankpin galling and developing excess clearance. The engine will develop a rattling sound on idle, telling me it is time for replacement. This happens around 50 hours of running, I am flying almost everyday and around one hour sessions.The engine is running perfect otherwise using a APC 14x8 giving it 9000 Rpm on ground, Klotz oil at 25:1 mix,95 regular. I am meticulously monitoring the engine setting to avoid any lean setting,the plug does not burn out and the piston crown and head are evenly black colored.
This has happened several times over the years, Os had a mod on the retaining screw, to cut the flanges off for better lubrication, did not change anything.I think the bearing is too small, causing high wear on the pin?
I am having problems with the crankpin galling and developing excess clearance. The engine will develop a rattling sound on idle, telling me it is time for replacement. This happens around 50 hours of running, I am flying almost everyday and around one hour sessions.The engine is running perfect otherwise using a APC 14x8 giving it 9000 Rpm on ground, Klotz oil at 25:1 mix,95 regular. I am meticulously monitoring the engine setting to avoid any lean setting,the plug does not burn out and the piston crown and head are evenly black colored.
This has happened several times over the years, Os had a mod on the retaining screw, to cut the flanges off for better lubrication, did not change anything.I think the bearing is too small, causing high wear on the pin?