Magneto
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Don Madden
- Member
- Posts: 2882
- Joined: Mon Jan 01, 1990 12:00 am
- Location: USA USA
Magneto
Magneto gear is very tight fit on a taper shaft & requires a special puller. Jampot Spares does list them but contact your nearest section to see if one can be loaned.
If you are not familiar with magnetos nor have ready hands that are, DO NO HARM. I suggest you limit service to cleaning & setting contacts & checking the ground brush & HT pickups & leads, or removing the complete unit for repair. The slip ring may have carbon deposits that short out the HT path. If not taken apart correctly, you will damage expensive parts.
Many things can cause lack of spark, from fouled plugs, poor HT leads, dirty and/or improper gap of contact or internal failure. The cut-out push switch or its' wire can short out. Has anything been changed since it ran well? First clean the contacts & set to 0.012in where they first open fully in the forward direction & try a known good plug to test, then if no spark remove the rear pickup from the body & inspect that & the slip ring. Let us know how you are doing.
Cheers, Don.
If you are not familiar with magnetos nor have ready hands that are, DO NO HARM. I suggest you limit service to cleaning & setting contacts & checking the ground brush & HT pickups & leads, or removing the complete unit for repair. The slip ring may have carbon deposits that short out the HT path. If not taken apart correctly, you will damage expensive parts.
Many things can cause lack of spark, from fouled plugs, poor HT leads, dirty and/or improper gap of contact or internal failure. The cut-out push switch or its' wire can short out. Has anything been changed since it ran well? First clean the contacts & set to 0.012in where they first open fully in the forward direction & try a known good plug to test, then if no spark remove the rear pickup from the body & inspect that & the slip ring. Let us know how you are doing.
Cheers, Don.
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A Moderator
- Posts: 50
- Joined: Wed Oct 12, 2005 10:45 pm
- Location: UK
Magneto
Moved from frequent questions to here as a more appropriate location.
Frequent questions is a section where constantly recurring questions will get moved to so that you may already see the answers to questions that have been asked many times in the past.
Frequent questions is a section where constantly recurring questions will get moved to so that you may already see the answers to questions that have been asked many times in the past.
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Malleon
- Posts: 1329
- Joined: Sun Jan 01, 1995 12:00 am
- Location: WREXHAM UK
Magneto
Kevin,
After checking the points gap as per Don's advice, remove the H.T. pick ups andexamine the carbon brushes. If the brass contact on the slip ring is worn, a 'step' can develop at the ends of the contact; then if the engine kicks back when starting due to over advancing the mag. control it can break the brush(es). Clean the slip ring with a petrol moistened cloth to remove any carbon deposits.
As Don said, let us know what you find.
Best regards.
After checking the points gap as per Don's advice, remove the H.T. pick ups andexamine the carbon brushes. If the brass contact on the slip ring is worn, a 'step' can develop at the ends of the contact; then if the engine kicks back when starting due to over advancing the mag. control it can break the brush(es). Clean the slip ring with a petrol moistened cloth to remove any carbon deposits.
As Don said, let us know what you find.
Best regards.