1985 25hp Johnson - problems starting

H

hackbrew

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Nov 28, 2001
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I have just acquired a 1985 25Hp Johnson outboard that won't start. It has the CD2 ignition system. My compression is low at 80 PSI, I have tried feeding a little fuel right into the cylinder, and I have a good blue spark. Although, it has me puzzled that the spark from one of the cylinders fires about 2 times per revolution, where as the other cylinder fires once per rev. I have changed the powerpack with no change. I guess it must firing at the wrong time, although I'm not sure why the other cylinder won't at least pop. I believe the answer may be in the charge coil or sensor coil under the fly wheel, but I don't know how to test them. Any idea's? Should I look somewhere else?
 
JB

JB

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Re: 1985 25hp Johnson - problems starting

Ahoy, Hackbrew. Try spraying WD-40 into the carb(s) while trying to start her. If she doesn't pop then, your flywheel may have sheared the key and gotten way out of time. <br /><br />On the compression issue, I agree 80 is quite low, but she is cold. Check what happens to the compression with a bit of oil in the cylinder. You may have stuck or carboned up rings.<br /><br />Let us know what you find.<br /><br />Red sky at night.. .<br />JB :)
 
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hackbrew

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Re: 1985 25hp Johnson - problems starting

JB:<br /><br />Thanks for the reply! I should have mentioned that I had it running for about 10 seconds, but I saw no water output, so I shut it down and replaced the water pump and thermostat. The key could be a possible answer, but do you have any idea why I would be getting multiple sparks per one revolution of the flywheel?
 
JB

JB

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Mar 25, 2001
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45,907
Re: 1985 25hp Johnson - problems starting

Sounds like fuel starvation, Hackbrew. Check that your fuel pump makes a strong squirt when you turn her over. If that is okay, clean your carb(s). If it isn't check fuel lines and tank, etc., and overhaul your fuel pump.<br /><br />The double spark is probably from inductive coupling with no load. Shouldn't happen with a load on the system.<br /><br />Red sky at night. . .<br />JB :)
 
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