No spark on one popper

[boltbreaker]

Hello. I've got a stumper. It's a 1971 4 HP mercury with the thunderbolt igintion system with points.<br /> I replaced on the corred wiring with new and filed the points and the engine had good hot spark. I then went on to degrease and wash the engine, clean the carb, and replaced the impeller.<br />Put it in the tank and NO SPARK. Now I know what you are thinking, the points are wet. Not the case. I pulled the flywheel and ran a dollar bill across them. Everthing is dry in there.<br />I think the points are "grounding" somewhere. I can hook up my dmm and when turning the crankshaft to where they are supposed to be "open" and I can still get a resitance reading. I'm testing from the wire the runs out of the points. Restance lower when they close, but am isn't it supposed to be an "open" circuit with points open? (i.e. should show infinite resistance)<br /><br /> Any idears?

 

[Laddies]

Re: No spark on one popper

The insulater on the pt stud has drove many to the bar, replace it--Bob

 

[boltbreaker]

Re: No spark on one popper

The insulator is cracked.... I can't see how it would still ground out...it's gounding somewhere though. All the pieces are there I can just see and feel hairline cracks in it. I get a reading of 3.6 on 20k when open, then 0 when closed. I just cleaned removed the points, set them back in there and it did fine with flywheel off. Put flywheel back on and it reverted to teh same condtion. I think I might have a used insualtor.

 

[boltbreaker]

Re: No spark on one popper

The insulator is cracked.... I can't see how it would still ground out...it's gounding somewhere though. All the pieces are there I can just see and feel hairline cracks in it. I get a reading of 3.6 on 20k when open, then 0 when closed. I just cleaned removed the points, set them back in there and it did fine with flywheel off. Put flywheel back on and it reverted to teh same condtion. I think I might have a used insualtor.

 

[boltbreaker]

Re: No spark on one popper

I swapped out the insulator and wa-la, she's cured!<br /> You are a genius.<br />It had a hairline crack in it through the top, and I still dont' see how it was grounding.<br /> I was bout ready to pull my hair out trying to figure out what was wrong... even starting thinking against the normal rationals.... thanks for saving my sanity!<br /> -B-