Johnson 6hp - odd transmission prob?

[timapexcomputer]

Hey all Tim here how's everybody doin?

I was hoping to tap in to the wealth of knowledge you guys have... but not for my Checkmate. Quite the opposite actually - my sailboat (MX-16 is running fine thanks to you guys)



Sailboat has a 1980 Johnson 6hp that has been flawless all summer. However today, I backed out of the slip and it felt like something was holding me back... almost like the boat was dragging bottom or something.

Slid the motor from reverse to neutral after backing up and the motor revved right up. I realized I had the throttle much higher than I had thought.

I quickly wound it back down and slipped it in to Forward. The rev's dies right down so I throttled up - but the motor struggled. I played with the throttle thinking carb might be gummed up but it wouldn't rev up. Then it died.

So it starts and runs great, but when you put it in gear it has major resistance. Thoughts?

 

[Bill Gohr]

thats a 1971 in the pic, and the only way that gearcase can do what you re saying is if is full of water, or nothing at all, it is all bronze bearings inside.

 

[Bill Gohr]

or theres a bunch of crap wrapped up behind the prop

 

[sim]

or theres a bunch of crap wrapped up behind the prop

Yes. Have you pulled up and looked for a bunch of nylon crap behind the prop?

 

[timapexcomputer]

Hey all - thanks. Sorry yes it is not a 1980. I was confused between two motors. Anyway yes I took the motor home withe me so it is in the garage. I hadn't had a chance to check much, but I did make sure it free spins in neutral very well, and then locks in either gear.

So should drain geal oil and make sure it i still gear oil and not water/empty?

 

[timapexcomputer]

UPDATE

Drained the gear oil and she is as clean as the day I put it in at the beginning of the season. No water... Going to pull the prop now to look for clues

 

[timapexcomputer]

Prop is clean as a whistle.

Spark plugs out, pulling the rope in gear is easy and everything spins as it should. The shifting seems lined up perfect too.

Im stumped...

 

[Chris]

Just to clarify....does it seem to run fine?

Or does it run poorly?

Like the other guys suggested it sounded like a gearcase issue from some of your first posts, then later it sounded like it was running poorly.

If it's more of a gearcase issue, perhaps you could have spun the hub in the prop, I'm not sure if your model has a shear pin that broke, or perhaps the clutch dog is damaged.

-Chris

 

[timapexcomputer]

Hi. No it runs great. Shear pin is ok. Everything seems great. Just wont rev'd up in gear

 

[timapexcomputer]

Solved! Bad spark plugs... yup. Odd? They fired enough to run and rev up, but not enough to produce enough power to move a boat.

Thanks all

 

[mouse4x4]

put you some split fire plugs in there they clam 5hp per plug heck she would be a 16hp then