Cylinder head shocking me 1957 35hp evinrude

[sqrl42]

Discovered the hard way that my cylinder head is electrified.. Touch the top near the spark plug and it Kills the engine like a kill switch.

Possible ark between spark plug wire connection and plug to head?

[reivertom]

Maybe an age crack in a plug wire?

[sqrl42]

new wires and boots last year, no cracks.. top cylinder was having a hard time firing off under lode on the water. figure the shock has something to do with it.

[ray-schaber]

Check the resistance from the head to the block with an ohmmeter. May be sealer insulating it from grounding.
Ray

[fleetwin]

touching the cylinder head kills the engine?? Do you get a shock as well? Does this engine have a stop switch? Is it electric start?
I’m thinking you are correct, whatever is messing up cylinder #1 is probably to blame for this shocking situation as well….

[sqrl42]

Yes, touching the Cylinder head shocks me and kills the engine.
No Electric Start
No kill switch
New cylinder Head installed a couple of days ago, I did repaint it before mounting.
possible the head is not grounding with the block, is this an issue?

I’ll take rays advice and do a resistance test this afternoon, if the weather holds up.

[aquasonic]

Wouldn’t the cylinder head always be grounded to the block by the 10 cap screws. Even if sealant is used, there should be continuity between the head and block. Somehow the spark seems to traveling on the outside of the sparkplug. Have you tried another sparkplug?

[frankr]

It seems almost impossible for the head to be electrified without the whole engine being likewise. It’s all bonded together by nuts & bolts. Very interesting.

[Mumbles]

quote Squirrel42:

I did repaint it before mounting.

The paint under the bolt heads could be the problem. I’ve never heard of it happening before but anything is possible.

Just thinking, but if the head had a poor ground, it would affect both cylinders, not just the one.

[chinewalker]

What plug wires are you using? How about plugs?

[Author]

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