1983 15 hp Johnson o/b that just won't run right!
			 
			 
			
		
		
		
			
			I'm leaning on a bad stator on this one.  When they get hot, the 
windings expand and if something's broken loose the spark sucks until 
it gets cool again. 
 
When it's cool and running fine, hook one plug wire up to an external 
spark plug that's grounded to the block so you can see the spark. 
Note how the spark looks. 
 
Then, when it's running like crap, do that again and see if you don't 
see a real thin, wimpy weak spark that compression can blow out the 
fire to..... 
 
I had a stator on an Evinrude 3-cyl 55 that worked great whenever a 
mechanic was looking at it because, in his haste, he never got the 
motor hot enough to make it fail.... 
 
Gets hot under that flywheel..... 
 
 
 
On Tue, 12 Aug 2003 02:27:34 GMT, "Bill Lavernoich" 
 wrote: 
 
 The problem with the 15 hp is as follows. 
 
I bought this motor two years ago from a guy who claimed to be selling it 
for the wife of a deceased friend. He didn't have much info on the engine 
except to say it had not been run in at least 5 years. (I willing to bet it 
was like 10 or more years.) 
 
Although originally I could not get it started, I've now had it serviced by 
three different repair shops, all with OMC backgrounds. It's been 
decarbonized, had the carburetor cleaned and rebuilt, new plugs and had 
numerous other minor issues resolved. The water pump hasn't been overhauled, 
but the mechanics have all claimed that the impeller is fine as the engine 
produces a sufficient "pee-stream." However, the big problem hasn't been 
solved. 
 
When the engine hasn't been used overnight or for a few days, it starts on 
the first or second pull and will idle OK. It will also run fine under full 
power on that first run and push our 14ft aluminum skiff at 20-25 miles an 
hour. From that point the reliability goes downstream fast and has me ready 
to use it as an anchor. 
 
The fun starts when the engine will not idle after being run at full or half 
throttle. It will also not restart easily if it is hot and/or has stalled 
out. You can sometimes get it started if you override the neutral-start 
interlock and immediately give more throttle than the "over-rev" limiter in 
neutral will allow. I know it's dangerous and for that reason won't let my 
kids drive it. Letting it sit for a while, an hour or so, gives you a better 
shot of restarting it, but not reliably and/or keeping it running. 
 
Ironically, when I've picked it up, all the shops have told me how great it 
runs in the test tank; they claim it starts right up, idles nicely and runs 
as well as can be expected for this age motor. I don't doubt that it does 
(in their test tanks), but I think they're all missing something. On the 
other hand, I'm sure they think I'm neurotic about this engine. 
 
Any thoughts suggestions or insights would be greatly appreciated. 
 
Bill Lav 
 
 
 
Larry 
 
Extremely intelligent life must exist in the universe. 
You can tell because they never tried to contact us. 
 
		 
		
		
		
		
		
		
		
		
	
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