Clutch Problem Johnson 15 HP

dWils

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I have a 1977 Johnson 15 hp that has started losing power/torque at full throttle going forward. It seems like the clutch is slipping. Before I tear into it, does it sound like that to you and how much of a problem is it to correct?
 

tashasdaddy

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Re: Clutch Problem Johnson 15 HP

sounds like a spun prop. not a gearcase problem. clutch dog problem. it acts like you hit a log and comes back.

take a permanent marker, draw a straight line, to match cotter pin. like the picture. take the boat for a spin, make it do what it is doing. if the lines are still line up, it is not the prop, if misaligned, the hub in the prop has slipped, and need to have a new hub installed by a prop shop, or a new prop.
 

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dWils

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Re: Clutch Problem Johnson 15 HP

Thanks, I'll try that. From the other FAQ's that makes sense. I appreciate your help and fast reply.
 

dWils

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Re: Clutch Problem Johnson 15 HP

I just tried that and the scribe marks stayed in alignment. So...????? Guess it's a trip to the shop? Thanks, unless you aor anyone else has any other suggestions.
 

petryshyn

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Re: Clutch Problem Johnson 15 HP

if its a SMOOTH transition from good torque to slipping, look for:

-incorrect trim
-motor height
-new additions to the transom which could cause cavitation (fish finder transducers etc.)

If its harsh like tashasdaddy suggests, onward to the shop!
 

tx1961whaler

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Re: Clutch Problem Johnson 15 HP

I just tried that and the scribe marks stayed in alignment. So...????? Guess it's a trip to the shop? Thanks, unless you aor anyone else has any other suggestions.

Just checking, but you did try it on the water? It won't slip unless under a load.
 

dWils

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Re: Clutch Problem Johnson 15 HP

Hi Fella's, Thanks for your attention. I got to looking at the opicture from Tashasdaddy's post again and I didn't mark the hub of the prop. So I tried it again, (both times in the water- I live close to the lake) the scribe marks didn't match up on the hub of the prop so I surmize that it is a slipped hub. I'll take it in for repacking or replacement, whatever. You guys are great. Thanks a lot.
 

tx1961whaler

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Re: Clutch Problem Johnson 15 HP

Yep, sounds like a slipped hub. A prop shop will fix it right up.
You must be close to the water, since 2 of your previous posts were only 45 minutes apart when you were checking the hub.
 

dWils

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Re: Clutch Problem Johnson 15 HP

Yep Lt., Just 3 miles to the my little lake. Lovin' it! Prop shop tomorrow. Thanks again you all!
 
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