'78 25 hp johnson-acts like it wants to slip out if gear

Chip P

Cadet
Joined
May 27, 2007
Messages
17
Motor runs great and it has a new prop, but something is jerking and it acts like it wants to slip out of gear. A '78 johnson is supposed to have a 13 spline lower unit but this one doesn't. It has a '77 or older lower unit on it with a pin drive. As long as you hold the forward lever it doesn't do it as bad. Any suggestion? Do I need to get the right lower unit or just have this one checked out? Just wanting to see if there was anything I could do before taking it to the shop. Thanks!
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: '78 25 hp johnson-acts like it wants to slip out if gear

sound like the clutch dog is bad. the have very square teeth, and if the edges get worn, the will slip out of gear. you may better off hunting another lower, depending on cost and labor, you have to change clutch dog, forward and reverse gear to do it right, and will need all the seals. you can lookup the engine diagram at BRP-johnson.com , literature, engine diagrams.
 

flawatchdog

Recruit
Joined
Apr 26, 2009
Messages
5
Re: '78 25 hp johnson-acts like it wants to slip out if gear

I have the same problem but with a 74 johnson 25 hp. I have had the gears and clutch dog checked out and they are fine. Any other ideas
 
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