Magneto/ignition switch problem, question??

[lancef53]

I am having trouble figuring out a problem on my RV 8 with a superior 0-360 with bendix FI and two slick 4371 mags. The plane will start and run fine, but when I do a mag check, the engine dies when turned to L. I have checked the switch, and tried a replacement with the same results. The wiring seems fine, and when I pull all 8 plugs and spin the prop by hand, the plugs all produce spark when they should, whether the switch is on both, left, or right. The engine is a used engine, with 192 hours. It has been in storage for a little over 2 years, with storage oil and oil in the cylinders. I am just changing out the storage oil for regular oil, and was planning to run the engine for a while tomorrow to try and warm it up and clean the plugs off.

Could it be a simple fouled plug problem, or where should I look now? The plugs are a little dark, but the spark seems good when I spin it by hand. I can't seem to make any headway.

Thanks in advance!!

[DennisRhodes]

at the P leads ( removed from Mags) . Check for any grounds as you move any of the p lead wiring or other around in the both position. Should have ground on L when running on Right and vis versa. Should NOT have a ground when switch is in both at any time. Also BE CAREFUL as when the p leads are off ,the Mags are HOT. Might we worth removing a plug in each cylinder for this test. Good luck/ DRR

[lancef53]

OK, I will check the wires to the mags. I was thinking they were fine since the mags work on the both and L and R, but not while I am doing a mag check.

Thanks for the help!!