Help setting mag timing

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Just1nH
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Help setting mag timing

Post by Just1nH »

Possible to set mag spark timing with mag on engine. I split my left mag in 2 and the cw & ccw gear spun on me and the timing is off on that mag. Possible to time it without timing the engine? I’ve never worked on these before so little different learning experience.

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John Fenner
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Re: Help setting mag timing

Post by John Fenner »

Yes, rotate prop till keyway of the gear is aiming at center of case, you will see a beveled tooth, align the ccw dot of the distributor gear with it, the beveled tooth on the distributor gear shall line up with the center of the sight window at 25° tdc.
I never finish anyth,,,.

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Slidin Gator
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Re: Help setting mag timing

Post by Slidin Gator »

Just1n,

I put this together a while back so I could remember how to put my mags back together, I hope it helps ya.
Bendix 20 Mag Internal Timing.pdf
(448.35 KiB) Downloaded 158 times
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

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smokster
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Location: Interlachen FL.

Re: Help setting mag timing

Post by smokster »

good stuff right there

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Slidin Gator
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Re: Help setting mag timing

Post by Slidin Gator »

Just1n,

Make sure to download manuals from this site. There is a manual for Bendix mags at this link:
viewtopic.php?f=47&t=53847

Here is the Continental manual for the same mags:
Continental Magneto Manual.pdf
(2.5 MiB) Downloaded 71 times
Here are a couple more files that may be of use. I found this Mag Timing document on an aviation forum, it provides some useful overview.
Magneto Timing.pdf
(153.92 KiB) Downloaded 74 times
The instructions below cover operation of a mag timing buzz box. The buzz box is pretty cheap (about $30) and it allows you to set timing by yourself. Without the buzz box you (or at least I) need one guy to move the prop and another with a feeler gauge (or business card) to find the point that the points open at.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

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John Fenner
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Joined: Tue Feb 14, 2012 12:26 pm
Location: Miami(Cuba) Fl.

Re: Help setting mag timing

Post by John Fenner »

With capacitor and coil disconnected from points, a test light hooked to positive battery terminal and probe the point terminal till it just lights is good, a dvom is just as good if not better, no disconnect needed of coil etc.
I never finish anyth,,,.

KRS62
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Re: Help setting mag timing

Post by KRS62 »

Sidin gator, if that is your stuff that you put together...thank you! I already had it all saved and read it over many times. It was the best, most concise info I found in my many hours of looking around for info!!! I will keep digging and report back.

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