No Spark on top Cylinder

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JRyno10

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6hp 1968 - 6802R Evinrude engine - started running on 1 cylinder mid trip. Runs perfect on 1 cylinder. I figured the coil went bad, and the coils actually look very good. Next guess is the points are dirty, however when we pulled the flywheel and looked at the points I noticed 1 set of points was touching and the other set was - and im not sure which is correct and which is not?
 
Curious if you confirmed/tested that both coils are good via a spark plug tester, or ground plug to engine, crank to see blue spark or swap the coils around and see if other cylinder not fire? I have never been able to confirm a coil is bad just by looking at it.
 
I recently had a no start situation after two days of perfect running. No spark to either of two plugs by grounding them to the block. All resistance readings were correct so changed both plugs and started on first pull. Even with new plugs couldn't see any spark by grounding plug to the block. ?????????????????????????????????
 
If you look closely at the shaft there is a lobe or cam on it that will open and close the points as the shaft rotates that is why one is open and one closed. The cam should have a line making TDC and that is the point you want it at when setting the gap in that point then move it around to the other point and check/set it.
 
Unless you have the proper tester, going after this ignition system with zero knowledge can be frustrating.
First off....old coils are not deemed good for service by "looking good".
Second, a previous post indicated a cam. He is correct. If you look, you will see that part of the points assembly rides on this cam. On this cam is the word TOP This is important. If you don't see it then pull it off and take a look. Obviously you have to remove the flywheel to look.
When a set of points is at the high side of the cam they will open. It is at this point that you can set the points gap at the proper .020" setting. Set it loose or watch the arm to make sure it is not moving when you slide the feeler gauge in. Only one set will be open at a time. Clean the contact surfaces with emory cloth and de-grease.
On a 1968 engine a field test for coils can be to remove the coil from the block and lay it on paper towels away from the block. Leave your electrical connections intact. Use the paper as an insulator. Spin the engine over and see if your spark comes back. If it does and then goes away again when you re-install the coil you will need a new coil as it is arcing to ground.
You should be able to fire across at least a 1/4" gap. Just grounding the plugs against the block is a cross your fingers and hope for the best kind of test. Up to you what kind of quality workmanship you put into this project.
 
Thanks Pappy and RAMROD. I think I may be in over my head on this fix. However I was able to figure that (the gap) out by watching a video and the gap was good. I purchased a feeler gauge at AutoZone and it was 0.20. Should I just go ahead and replace the coils?
 

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