1976 Johnson 115...Wow, i need serious help

GKT

Seaman Apprentice
Joined
Jul 9, 2010
Messages
43
Okay, I've been workin on this motor for a while. The motor will start up and run relatively fine. It runs and idles with lots of smoke from the exhaust though. Blue smoke. More than other two strokes i've noticed. Also theres always gray sludge comin out the prop(unburnt oil). Oh, and it vibrates a little when i run it on the water.
So, i thought it was firing right and i was right. Put a timing light on it and all plugs are firing except for #1. Two of the coils are cracked by the way. So i switched the coils around and #1 cylinder still wasnt firing. So i switched sensor #1 in the powerpack with sensor #3 and switched the spark plug leads between cylinders 1 and 3. No firing on #3. This tells me that the power pack is bad right?
Well, i pulled all the plugs and all of them are wet and black. I don't get it...i have spark in three and theyre ALL wet and black. and i recently redid the carbs so theyre definately okay. Fuel system seems to be good...only thing i can think of is something to do with the ignition. Maybe its the timing?

When the boat is running and i hook up a volt meter to the battery i should get about 14 or so volts correct? Im only gettin about 12.8-12.9. I took motor wire off battery while running and i got about 37volts at idle. Stator is okay right?

ALSO... i noticed just recently that the thermostat appears to be stuck open. Im gettin water coming out the exhaust relief even when i first start it up. Scared about changing out thermostat though because the bolts are severely rusted.
HELP PLEASE....are all of these issues related?
 

GKT

Seaman Apprentice
Joined
Jul 9, 2010
Messages
43
Re: 1976 Johnson 115...Wow, i need serious help

I did all kinds of ohm tests to stator and rectifier and powerpack and everything...everything checks out
 

Daviet

Fleet Admiral
Joined
Sep 24, 2008
Messages
8,958
Re: 1976 Johnson 115...Wow, i need serious help

You didn't mention compression, did you check it?
 

GKT

Seaman Apprentice
Joined
Jul 9, 2010
Messages
43
Re: 1976 Johnson 115...Wow, i need serious help

compression checks out good on all cylinders
 

Daviet

Fleet Admiral
Joined
Sep 24, 2008
Messages
8,958
Re: 1976 Johnson 115...Wow, i need serious help

Compression, spark and fuel is all it takes.
Compression good, spark good, except 1 cylinder.
Correct spark problem and see how it runs, if it still runs poorly I would check carbs.
Some times low voltage can cause ign problems, might want to correct charging system first.
 

GKT

Seaman Apprentice
Joined
Jul 9, 2010
Messages
43
Re: 1976 Johnson 115...Wow, i need serious help

ill order some parts ..see what happens then. 4 new coils, new power pack, new rectifier (red lead looks terrible...corrosion and half of the wire is broke...could be part of my problem)
 
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