need help 35 hp johnson troubles

[imported_rusty]

ok its a 1983 johnson 35 hp its on my 16 foot jon boat when i am running it seems to or i should say it seems the prop stop turning like its hitting mud then goes again it did it once last year and had it checked out it ran fine in the test tank he thought maybe i pick up a bag on the prop .is there a clutch type thing on the prop i thought someone told me once not sure. hope to get back on the water this week during high tide to double check it out what else to check ouy? thanks

 

[MCM]

Re: need help 35 hp johnson troubles

Rusty, do a search for spun prop, its where the prop is or has begun to seperate from the prop hub.

 

[imported_rusty]

Re: need help 35 hp johnson troubles

i just put on a new prop last summer after i took it out of the water (after duck season) from what i remember it looks like a metel prop with metal groves that slips on the shaft i dont recall seeing any rubber hub inside the prop that can give me slippage.

 

[MCM]

Re: need help 35 hp johnson troubles

The part with the grooves that goes over the splines on your prop shaft is the hub, its attached to the prop, sometimes they become seperated or loose. I suppose it could also be a slipping clutch dog inside the lower unit. The prop would be the first and cheapest thing to check. take a permanent marker such as a Sharpie and draw a from the shaft accross the bottom of the prop and up over the side of the prop, take the boat for spin and check to see if the marks still line up.

 

[MCM]

Re: need help 35 hp johnson troubles

Does the motors rpms increase when it does this?

 

[imported_rusty]

Re: need help 35 hp johnson troubles

i think it does dont want to say positive until i get her on the water again will put a line on the prop to check for slipping . it seems when i am just riding along it does that than goes again last only about 2 seconds when it first did it when i got to some deep water than gun it it went like a bat out of hell no problem i was coming back in during low tide so its possible i hit some soft mud will that do it? i remember i put the oar in to see hoe deep i got about 3 to 4 feet but by that time i was alredy pass the spot how does the clutch dog work? do i have on on my motor?

 

[MCM]

Re: need help 35 hp johnson troubles

The clutch dog is in the gearcase in the lower unit and yes you do have one. Soft mud could do it I suppose. The clutch dog is part of the shift mechanism, its purpose is assisting in shifting between reverse, neutral and forward. Somewhat like a clutch in a car only a little different.

 

[imported_rusty]

Re: need help 35 hp johnson troubles

so if not hitting bottom and prop not slipping then clutch dog? how hard to replace that any idear? thanks for the replys also mcm.

 

[MCM]

Re: need help 35 hp johnson troubles

No idea on replacement, it could be something else entirely, thats just one possibility, like the prop. It could be the shift/throttle cables need adjusting do to wear/slack. Take it out and see what happens w/the prop, try and keep track of when it does it and how it acts, also what you're doing when it happens, that will help diagnose it I think.