intermittent spark on one cylinder

gfem

Cadet
Joined
Nov 8, 2003
Messages
6
My 1997 9.9 Johnson two stroke has intermittent spark on one cylinder and pushing a 26 foot sailboat on one cylinder is very frustrating. The plug is good, the spark comes and goes. Any ideas greatly appreciated.<br /><br />Thanks-GM
 

Cricket Too

Lieutenant Commander
Joined
May 14, 2003
Messages
1,732
Re: intermittent spark on one cylinder

gfem....How do you know the plug is good. Just to be safe I would start with replacing that plug, it's a cheap start. Take a look at the wire and see if there is any rust or corrosion inside the boot. If that all checks out take a look at the coil, see if it has a good ground. Just some things to start with, check em out and get back. Good Luck.
 

gfem

Cadet
Joined
Nov 8, 2003
Messages
6
Re: intermittent spark on one cylinder

Thanks for the ideas, I will start with replacing the plug and checking the leads. Could be the salt water has corroded some of the wires under the insulation, so I will test for continuity. <br /><br />I lived in new York when I was a kid-Riverdale area and I have great memories of the city.<br /><br />GM
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: intermittent spark on one cylinder

GM - To isolate the problem switch the plug, ignition wire and coil between cylinders one at a time. When the problem moves from one cylinder to the other you know what component is causing the trouble.
 

gfem

Cadet
Joined
Nov 8, 2003
Messages
6
Re: intermittent spark on one cylinder

Thanks for the idea of moving the coil and ignition wire. I will certainly try this.<br /><br />GM
 
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