1976 Johnson 15 hp trouble

[Barracuda Bill]

I was using the in-laws little fishing boat (14' Lund with the aforementioned motor) when the motor started acting up. I was going about 3/4 throttle when it seemed like the motor was running out of gas, hit the squeeze bulb but no effect, then it died. Tried to restart but I couldn't turn over, the rope wouldn't move at all. I tilted the motor up put it in neutral and tried turn the prop, but that wouldn't turn. Of course, I did eventually make it to shore. What happened? How to fix?

Other info on the situation:
*motor gets very little use, maybe a couple of time per year
*little to no maintenance on the motor, probable in ever
*fuel mix was probably 50:1, the gas was from May of this year
*had used the motor Thurs and Fri with no problems. Saturday, the problem day, it wouldn't like to stay running at idle
*on the lake, I pulled the cover off and tried to turn the flywheel, but wouldn't turn.
*after we got it in, the motor would turn a little but very stiff
*I pulled the spark plugs and everything seemed ok in the cylinders, tried to turn over the motor with no plugs and still very stiff, no real difference than with plugs in
*tried to check LU lube, but couldn't loosen either screw
*didn't check for pee hole water that day, but was ok previously

Note-- this is the in-laws motor. I take care of mine.


Please help.

 

[orbanp]

Re: 1976 Johnson 15 hp trouble

Probably the best way to proceed is to find out that which part of the motor is stuck.
Take off the gearcase, just like when you change the waterpump, and see if it is the motor or the gearcase is that is giving the trouble.
You can proceed from there.

Good luck, Peter

 

[gozierdt]

Re: 1976 Johnson 15 hp trouble

From the sound of your symptoms, and description of the motor's usage, I suspect the
powerhead overheated, probably scoring a couple of the pistons. The cause of the
overheat was probably a failed impeller in the water pump. Drop the gearcase as
Peter suggests, and see what the impeller looks like. If the flywheel is still hard to
turn, you'll have to take the head off to check the cylinders. Use "LeeRoy's Ramblings"
for information on problems and general info on these motors:

http://www.leeroysramblings.com/#12_OB