Re: Mag drops with new engine
Posted: Fri Dec 02, 2022 1:46 am
That is an astute suggestion. A bad capacitor will act up with roughness, backfiring, and intermittent operation.n2582d wrote:Might want to check the magneto capacitor.
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That is an astute suggestion. A bad capacitor will act up with roughness, backfiring, and intermittent operation.n2582d wrote:Might want to check the magneto capacitor.
I don’t think they drifted, I think they were never set right. I should have left the plane at my mechanic (1.5 hr drive from home) when I found the big mag drop and the engine not idling below 1160rpm. Mechanic said it was ready to pickup, but he wasn’t there when I got it. I called him and he said to run it 5 hrs then tune it.Joe Moilanen wrote:I've never had my timing drift that much from new or rebuilt mags breaking in before. I don't think I've ever experienced more than 1 or 2 degrees drift for any reason, YMMV. I think I'd monitor the points gap if the trend continues?mmcmillan2 wrote:Mine do have the Bendex mags. Type S6LN-21. Overhauled 8/22.
That’s what my installer mechanic thought, but after cleaning plugs it was still dropping excessive. Had to adjust timing.Iurii S. wrote:Can a severe drop be due to the fact that you are switching off the upper plugs, and the lower plugs are fouled with oil due to new rings?
Thanks, will look into that.n2582d wrote:Might want to check the magneto capacitor.