intermittent spark on 1972 Johnson 9.5 with breaker point ignition

[Pipefitter074]

The motor starts and runs good sometimes, no spark at all other times,new points gapped correctly, new condensers, new mags, new solid core wires, new plugs. Kill switch disconnected, wires checked for shorts to ground. I am thinking my problem is the connection between the timing plate and the engine. The plate screws to a metal disc with 4 holes that sits captured under a brass cover plate held on with 3 screws. The Disc has ALOT of clearance around crankshaft and seems to be greased. Thinking maybe all that clearance might be changing point gap as it flops around Should this disk be able to float like 1/8” and should it be greasy, conductive grease?? Pulling my hair out with this problem!!

 

[timguy]

Maybe try a ground wire to the stator plate. Otherwise it might be too loose to get an accurate coil gap as well as point gap. If so, just find a tighter stator. The sleeves DO wear. Got planty here in my stash of parts.

 

[racerone]

Is the plate with the 4 holes upside down ?-----And grease has nothing to do with this issue.----That disc is loose and not the issue either.-----Did you screw wires into the new coils ?----Or run with a timing light to pinpoint loss of spark and which cylinder.----This should be easy to solve.

 

[Pipefitter074]

Maybe try a ground wire to the stator plate. Otherwise it might be too loose to get an accurate coil gap as well as point gap. If so, just find a tighter stator. The sleeves DO wear. Got planty here in my stash of parts.

 

[Pipefitter074]

Thank You

 

[Pipefitter074]

Is the plate with the 4 holes upside down ?-----And grease has nothing to do with this issue.----That disc is loose and not the issue either.-----Did you screw wires into the new coils ?----Or run with a timing light to pinpoint loss of spark and which cylinder.----This should be easy to solve.

Thanks

 

[racerone]

No need for a ground wire on these magnetos as a rule.

 

[Pipefitter074]

Thanks

 

[Pipefitter074]

Thanks

Got a new stator plate, as you suggested not worn. Old one was in flat side up, beveled side with square notch down, is this correct? Also it was covered with dark grease, should it be greased? Conductive grease?
Thanks

 

[racerone]

I use whatever grease is handy.-----Overthinking is common on this elegantly simple ( to me ) magneto.

 

[Pipefitter074]

I use whatever grease is handy.-----Overthinking is common on this elegantly simple ( to me ) magneto.

Thanks