89 Johnson cold running dead miss.

jbowser

Cadet
Joined
Dec 28, 2011
Messages
8
Hi guys, new to the forum, and impressed by the community! I have a 89 johnson 110 V4 that I picked up last spring.
I have been happy with the overall performance of the motor, but I do not have much 2 stroke experience and am relatively new to marine mechanics. I have been experiencing a dead miss when leaving the dock. A casual carb clean (no dissasembly)
seemed to correct the issue for about 2 months of 4-5 hrs of weekly use and then the miss came back. The motor will run on three until hot, and occasionally the fourth will pop. After 10-15 minutes and a mile or so out the fourth cylinder will come on like a switch was thrown, and the motor will run fine for the rest of the day. Is this a common problem? I would like to get it fixed this spring, but I am strapped for cash and don't want to spend a lot of money chasing the problem. Does this sound familiar to anyone? Any ideas of where I should start? Thanks a lot! Josh
 

Haffiman

Commander
Joined
Dec 17, 2009
Messages
2,454
Re: 89 Johnson cold running dead miss.

Start by taking a compression test. If you got one low cylinder, there is your answer.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: 89 Johnson cold running dead miss.

Do a cyl drop test on it when the problem occurs. That's pulling one plug wire off at a time with an insulated pliers to narrow it down to a cyl/cyls.
 

toddschubert

Chief Petty Officer
Joined
Sep 3, 2011
Messages
504
Re: 89 Johnson cold running dead miss.

Boobie sounds right. Could have a spark wire grounding out someware like rubbing on head cover or something
 

jbowser

Cadet
Joined
Dec 28, 2011
Messages
8
Re: 89 Johnson cold running dead miss.

Thanks for the responses thus far! I did a comp test when I bought the motor and all cylinders were within 5 psi. I have not isolated the cylinder with the miss yet, but I have checked for loose or shorting wires and found nothing. I will do another compression test in the spring just to see where I am at, but I would be surprised to see a low cylinder.
 
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