Hi guys,

Trying to slowly disassemble the engine on my M20 and had a question regarding the removal of the Magneto

I bought the puller tool, got it screwed in and tried loosening the nut attached to the gear and it wasn't budging.

I consulted the service manual, but as it can sometimes be, was a bit vague. How do I get this bugger off?

Brian, I'm new to these bikes and engines but can actually offer you advice on that. First of all I haven't read all the manuals but I marked my gears so they'd line up later just in case. Take that nut off first then use the extractor. You still have the gear bolted in place. I jammed a rag in the gears to stop it from spinning when I was ratcheting it out and it came off easy. Once that's out it will make sense. Back up the extractor bolt and screw the extract in place of the threaded nut that was holding the gear in place. Mine pulled out rather easily.

Good luck
John

email (option): jangofla@gmail.com

No need to jamb the gears; use one wrench to hold the extractor body once it is screwed home into the magneto gear, and another wrench to turn the extractor screw. If the gear does not free easily, a sharp tap or two can be applied squarely on the end of the extractor screw with a mallet which should break the gear free of the magneto shaft taper. Normally the gear will break free of the taper easily without the use of force beyond the extractor pressure; always the preferred method as banging on the magneto is not optimal practice.

email (option): teladelujo@msn.com

You have to remove the magneto drive gear retaining nut before you use the extractor to remove the actual gear...

When you have removed the nut you will see the inside diameter of the gear is threaded. Back off the centre bolt of the puller and screw it into the gear using the larger external thread.

When it is screwed fully home screw in the centre bolt of the puller.
This will bear onto the end of the mag armature and when tightened this provides the motive force to remove the gear from its taper...

Use a spanner to hold the body of the puller to prevent it turning and then tighten the centre bolt....They generally come away quite easily if you apply some pressure to the bolt and then give the spanner a sharp tap with a copper/aluminium mallet...As is usually the case with tapered assemblies the initial breaking of the taper fit requires a light application of 'shock'...Ian

email (option): ian@wright52.plus.com

Marking the position of this gear won't help you as it's on a tapper and not a keyway. When you time the mag again you'll have to get the points in the "just opening" position with the engine at the correct degrees and tap the gear onto the tapper. Rotate the engine all the way round and check the timing again before tightening up the nut.

email (option): horror@blueyonder.co.uk

Though you indicated you had a service manual, here's a link to the Air Ministry’s version of the M20 maintainance manual which is very helpful.

http://www.carlsalter.com/download.asp?p=402

email (option): teladelujo@msn.com

I now use an impact gun on all pullers.
The jerky motion of impact / rattle guns usually pulls all tappers strait off, includngthe dreaded clutch hub

email (option): wariron@tpg,com,au

Success! Thanks for the help, gents.

Now for the next question: I want to get it disassembled cleaned up and put back together. Having never done one of these before, what is the difficulty level?

I'm open to the idea of having someone else go through it and put it back together, but I'd like to handle the cosmetics.

Are there any people in the states that rebuilds these?

Unless you wish to use this as an opportunity to hone your magneto rebuilding skills, call this fellow; Ed Strain will do a great job on your M01 magneto, but does not do generators... Do a google search and you'll find nothing but great reviews from numerous bike and car guys.

He takes calls early in the workday, but you will have to leave a message after about 9AM

PS: your magdyno appears to in reasonable shape externally, always a good sign...!

Edward Strain Inc
6555 44th Street
Pinellas Park, FL 33781
(727) 521-1597

email (option): teladelujo@msn.com

Brian,

I'm in Florida and just saw the response from John Edwards with regards to magneto repair / rebuild. I would greatly appreciate if you'd let me know what you find out via email. Nothing I can do now as heading out on vacation this week but might consider doing same if reasonable.

Thanks
John

email (option): jangofla@gmail.com