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Mickey
 
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Default Fouled plugs...1986 100hp Johnson Comm

I took my 1986 Johnson 100hp Comm out for a test run with mixed results. The
timing linkage came apart then the fuel line slipped off at the connection
to the motor. Once all that was straightened out the motor popped the boat
right out of the water and up to WOT rpms of 5000 with grins all around.
Then the motor all but stopped cold and was hard to turn over. With a little
begging it started again and we limped back to the dock as the motor
wouldn't pick up speed at all. The next day I took it out minus the cheering
section (two stepsons) and it ran the same just bogging down when the
throttle was increased. Trying not to make too many changes at once and
remembering that every time I messed with the sparkplugs it ran better I
took the boat out and put new plug wires on it as the new spark plugs were
on the way but won't be in until tomorrow.

Taking the boat out again without messing with the spark plugs and the new
wires on it did the same thing just bogging down when the throttle was
applied. I limped back to the dock and pulled two plugs on the starboard
side just cleaning them off with a paper towel. After putting the plugs back
in the motor it idled better so I took it out and the performance that I'd
seen before was there for a couple hundred yards then it was back to the
bogged down motor again, could it foul the plugs that fast?

I rebuilt the carbs, new thermostats, new water pump, new Holley "blue" fuel
pump with a regulator set at 5 psi to replace the VRO and a 50:1 fuel mix in
the tank. I have Champion L77CJ4 in the motor right now and NGK BUHXW-1
surface gap plugs on the way which I hope will solve the problem. Could an
improper setting on the floats cause such a problem as I didn't have the OMC
gage to set them up with? Would anyone have the specks on that gage for the
100 hp Comm?

Thanks Mick