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Clams Canino
 
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Default 1983 15 hp Johnson o/b that just won't run right!

Low speed winding to be specific. (assuming Jonnyrudes have one)

-W

"Larry" wrote in message
...
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 a

n
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.