1972 Johnson 50hp Will only start with one plug removed

david4456

Recruit
Joined
Jan 7, 2013
Messages
5
Thanks for your help in advanced,

I have 1972 50hp Johnson, it was running fine the other day on the water and then just stopped.

It will only start on one cylinder and yes it has fuel, compression and spark to the other.

It will idle on one cylinder and even if i just cover the other spark plug hole with my thumb it instantly stalls. it must have to do with the increase cylinder pressure.

Does anyone know what I am looking at to fix the problem and is it an easy fix?

Thanks

David
 

Bosunsmate

Admiral
Joined
Apr 7, 2012
Messages
6,129
Re: 1972 Johnson 50hp Will only start with one plug removed

Does it matter which cylinder you cover?
If not it could be a headgasket failure- an easy fix
 
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