- Joined
- Apr 13, 2010
- Messages
- 203
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- 38
Plane is in the workhop for a complete repaint and an annual.
Shop found a completly shot exhaust system - will be replaced, no doubt.
Besides the crack(s), the material looks annealed. Muffler is distorted (can't find the picture right now).
Why is this? EGT too high? I wasn't aware that our plane's exhaust systems could run too hot.
First exhaust, 3093h in service. Engine O540 B4B5, 1700h, 7.2 compression ratio, runs under Petersen Mogas STC. 2/3 to 3/4 of the time use of Mogas, Avgas100LL only when Mogas isn't avialable. Engine instrumentation: just the stock EGT gauge. We run the engine 75°F rich of peak and typically in the 8000" to 12000" altitude, so less than 75% power - should keep us out of the "red box". On sight seeing flights down low we run at 55% to 65% power. LOP is not possible with this particular engine, running too rough for my comfort.
And, by the way, leaky gaskets caused all flanges to erode . This will cost some serious cash
Comments on the possible cause welcome
Markus
Shop found a completly shot exhaust system - will be replaced, no doubt.
Besides the crack(s), the material looks annealed. Muffler is distorted (can't find the picture right now).
Why is this? EGT too high? I wasn't aware that our plane's exhaust systems could run too hot.
First exhaust, 3093h in service. Engine O540 B4B5, 1700h, 7.2 compression ratio, runs under Petersen Mogas STC. 2/3 to 3/4 of the time use of Mogas, Avgas100LL only when Mogas isn't avialable. Engine instrumentation: just the stock EGT gauge. We run the engine 75°F rich of peak and typically in the 8000" to 12000" altitude, so less than 75% power - should keep us out of the "red box". On sight seeing flights down low we run at 55% to 65% power. LOP is not possible with this particular engine, running too rough for my comfort.
And, by the way, leaky gaskets caused all flanges to erode . This will cost some serious cash
Comments on the possible cause welcome
Markus