Here's one for the hive mind.
Since I rebuilt my Lycoming O-360-A1D last year, with 2x freshly-rebuilt Bendix Mags, there's no drop in RPM, rise in EGT, or drop in CHT whenever I turn off the Left Mag. It's not a broken P-Lead or other grounding issue. Whenever I do a ground check and turn off the Left and then the Right mag, regardless of RPM, the engine quits like it should.
I've read that maybe bad mag timing could cause this. But I've triple-checked the timing and both mags open the points at 25 degrees BTDC like they should. The engine runs just fine on the right mag. And I have no problem making static RPM or producing good power all the way up to altitude.
I have noticed since I finished the rebuild that the right side of the engine (#1 and 3 cylinders) run significant hotter in both EGT and CHT than the left side--to the tune of 50-70 degrees CHT and 100-150 degrees EGT on both. It does that both sitting on the ground and in flight, so it's not air flow. I've replaced the carb and the induction tube flanges and gaskets (with the SDS ones) to no avail.
I also have an RF filter on the right mag, which I just replaced with a new one.
I'm stumped. Any other thoughts out there?
My next move is to remove that RF filter and see if that does it. But I don't see how that could be the problem.
Thanks,
-Matt
N402BD
Since I rebuilt my Lycoming O-360-A1D last year, with 2x freshly-rebuilt Bendix Mags, there's no drop in RPM, rise in EGT, or drop in CHT whenever I turn off the Left Mag. It's not a broken P-Lead or other grounding issue. Whenever I do a ground check and turn off the Left and then the Right mag, regardless of RPM, the engine quits like it should.
I've read that maybe bad mag timing could cause this. But I've triple-checked the timing and both mags open the points at 25 degrees BTDC like they should. The engine runs just fine on the right mag. And I have no problem making static RPM or producing good power all the way up to altitude.
I have noticed since I finished the rebuild that the right side of the engine (#1 and 3 cylinders) run significant hotter in both EGT and CHT than the left side--to the tune of 50-70 degrees CHT and 100-150 degrees EGT on both. It does that both sitting on the ground and in flight, so it's not air flow. I've replaced the carb and the induction tube flanges and gaskets (with the SDS ones) to no avail.
I also have an RF filter on the right mag, which I just replaced with a new one.
I'm stumped. Any other thoughts out there?
My next move is to remove that RF filter and see if that does it. But I don't see how that could be the problem.
Thanks,
-Matt
N402BD