no spark on upper cylinder

chris812

Cadet
Joined
Feb 5, 2011
Messages
24
Hi, I was hoping someone might tell me whats going on. I have a 1964 28 hp evenrude I bought it used from someone and gave it a test run. Started then started missing, I guess there is another terminology for when it does that. Anyway I had to replace the head, replaced head and adjusted the points to .020 put it back together and test ran it again, Now there is no spark in the upper cylinder and good spark on the lower. Any ideas? Will the cut-out cause the upper to not fire? When my friend toughed the lower motor frame he said he got a shock. What does that mean?

thanks
 
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Cap'n Chaos

Petty Officer 1st Class
Joined
Jun 4, 2010
Messages
290
Re: no spark on upper cylinder

Sounds like you might need to replace the plug wires...

I'm pretty sure the points gap should be .020.... not .030
 
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cr2k

Captain
Joined
Mar 19, 2009
Messages
3,730
Re: no spark on upper cylinder

Plug wire or insulator could be bad also. Pull the flywheel back off and check everything.
 

JDusza

Ensign
Joined
Apr 21, 2009
Messages
934
Re: no spark on upper cylinder

In all likelihood, the missing was this electrical problem.
The electrical shocks are coming from the magnetos dumping the electrical energy to the engine frame instead of the spark plugs. You might want to try running the engine in the dark, looking for sparks to the frame from the spark plugs wires or elsewhere along the electrical path.
In addition, you should go under the flywheel and look for worn / broken wires shorting to the frame, cracked magnetos leaking to ground, connections, etc..
You'll get it.
J
 
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