Coming unglued in the flywheel!!!

kendunn

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Aug 23, 2010
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25
Thought I had an electrical issue, and I guess it still sort of is, with the firing on my 1990 200 johnson, but when I finally got the flywheel off I found all the epoxy was shot, even on the magnet that works the timing trigger (it was just twisting around the barrel of the flywheel). I have heard this is kind of an issue and they can just be glued back and the larger magnets are not a problem to figure where they go, but I need to get the sleeve timed. I think I know where it goes by looking at various imprints and stains left, but there is a little bit of doubt. Anyone know of a way to do this? There are 2 lines on the outside of it and if the inside key slot is set at noon, these come in around 2:30 and 7, but if I have a mic measurement from the center of the key to the others it would really help, or any other way to tell. Its odd, there looks to be a little notch in the bottom that slides over a nub, but no nub or sign of ever having been one.
 

Joe Reeves

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Feb 24, 2002
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13,262
My personal opinion....... The outer magnets coming loose presents no big problem if the epoxy repairs are done properly. The inner magnet assembly, I wouldn't mess with as the slightest degree off with the repair (if such repair has ever been possible) would result in a "No Run" scenario or a "Pre-Ignition) one where aluminum pistons melt.

If however, repairs of this type have become common, I' like to know about it... who had it done, by whom, and where?
 

Faztbullet

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Mar 2, 2008
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15,931
I don't recommend trying to repair the timing hub..I myself replace the flywheels.
 

ob

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Aug 16, 2002
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6,992
Funny...I had this very issue of the center/timer base magnet coming unglued form its factory epoxy just a few weeks back on my 70 HP. Mine had this notch you mentioned and a single paint mark on the corresponding surface. Mine didn't seem to have rotated away from this setting however the magnet could be simply lifted off of the flywheel inner hub. I thoroughly cleaned both the inner magnet surface and the flywheel hub with a small sharp scraper and some medium sand paper and epoxied it back in place at the specific notch and paint mark location using BRP magnet epoxy. Engine runs like a charm since. The reason I pulled my flywheel to begin with was due to erratic idle and a failing stator. I also replaced with a new timer base while I had it apart.
 

daselbee

Commander
Joined
Jan 20, 2009
Messages
2,765
My personal opinion....... The outer magnets coming loose presents no big problem if the epoxy repairs are done properly. The inner magnet assembly, I wouldn't mess with as the slightest degree off with the repair (if such repair has ever been possible) would result in a "No Run" scenario or a "Pre-Ignition) one where aluminum pistons melt.

If however, repairs of this type have become common, I' like to know about it... who had it done, by whom, and where?

Hey Joe...my hand is UP! I have done about 4 over the past 5 years.
It is VERY tricky to position the center magnet properly.
 

Joe Reeves

Supreme Mariner
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Feb 24, 2002
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13,262
Hey Joe...my hand is UP! I have done about 4 over the past 5 years. It is VERY tricky to position the center magnet properly.

Good for you my friend. I figured that if anyone could do it, it would be you.

I wonder why they ever drifted away from the metal perm magnet setup?
 

kendunn

Cadet
Joined
Aug 23, 2010
Messages
25
I'm pretty sure I know how it goes, and isn't there some timing adjustment on there?
 

ob

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Aug 16, 2002
Messages
6,992
I'm pretty sure I know how it goes, and isn't there some timing adjustment on there?

If the original factory timing adjustments were never moved and assuming that you can get the inner magnet epoxied back in it's original location , there should be no need for adjusting the timing.
 

kendunn

Cadet
Joined
Aug 23, 2010
Messages
25
If the original factory timing adjustments were never moved and assuming that you can get the inner magnet epoxied back in it's original location , there should be no need for adjusting the timing.
I mean just to tune in case I was very slightly off. I wish I had a mic measurement from the keyhole slot to the break lines in the magnet. These are not available anymore new, and if I get a used one I imagine the epoxy is near failing on all of them by this time
 

daselbee

Commander
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Jan 20, 2009
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2,765
I mad a detailed "map" of a good flywheel. I mapped out the location of the slots on the inner magnet in relation to the position of TDC mark, flywheel key slot, and really ANY fixed point on the flywheel that I could use for reference.

I used thin thread to create a straight line across the flywheel exactly 180* from one of my reference points. I counted flywheel teeth to get the proper position of a straight line across the flywheel that lines up with the slots on the center hub magnet..
It could even be you know maybe a half of a flywheel gear tooth....that's how precise I made it.

So, on my bad flywheel, then I found the same reference point, counted the teeth around, pulled the string across the flywheel, and lined up the proper slot
of the center magnet. I used two (or even more) reference points and string pulls to make sure I had it right.

This is hard to describe, but I hope you can figure out what I did from what I wrote.

Mark and glue with JB Weld. It took me about an hour to make the map with tooth counts and all, and about 30 mins to get one glued and repaired.
 

daselbee

Commander
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Jan 20, 2009
Messages
2,765
I have a few of these repaired and tested flywheels that I could let go for a very reasonable price.
 

kendunn

Cadet
Joined
Aug 23, 2010
Messages
25
I mad a detailed "map" of a good flywheel. I mapped out the location of the slots on the inner magnet in relation to the position of TDC mark, flywheel key slot, and really ANY fixed point on the flywheel that I could use for reference.

I used thin thread to create a straight line across the flywheel exactly 180* from one of my reference points. I counted flywheel teeth to get the proper position of a straight line across the flywheel that lines up with the slots on the center hub magnet..
It could even be you know maybe a half of a flywheel gear tooth....that's how precise I made it.

So, on my bad flywheel, then I found the same reference point, counted the teeth around, pulled the string across the flywheel, and lined up the proper slot
of the center magnet. I used two (or even more) reference points and string pulls to make sure I had it right.

This is hard to describe, but I hope you can figure out what I did from what I wrote.

Mark and glue with JB Weld. It took me about an hour to make the map with tooth counts and all, and about 30 mins to get one glued and repaired.
Great idea, hope I can find one, sounds a bit more accurate than using a micrometer. I don't suppose you had this flywheel and still have the map, do you? Mine has 120 teeth
 
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