7.5 Johnson shifting problem

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Turtle61

Recruit
Joined
May 5, 2013
Messages
4
I started up my 1978 7.5 Johnson today for the first time this spring with no problem. The problem started when I shifted into forward and revved up the engine to move forward. It started out okay but suddenly the motor raced like a sheared the prop pin. I checked the pin and that was okay. The motor runs okay but does not shift to either forward or reverse. Anybody have any ideas to what may be wrong?
 
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boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: 7.5 Johnson shifting problem

Got a model # ?? I don't believe they built a 7.5 in 1978. But I may be wrong.
 
T

Turtle61

Recruit
Joined
May 5, 2013
Messages
4
Re: 7.5 Johnson shifting problem

boobie said:
Got a model # ?? I don't believe they built a 7.5 in 1978. But I may be wrong.
Click to expand...

The motor is up at the summer cottage. I won!t be able to get a model number till next weekend. I am going by memory and we all know how that starts to go with age. It might be 1973.
 
Chinewalker

Chinewalker

Fleet Admiral
Joined
Aug 19, 2001
Messages
8,902
Re: 7.5 Johnson shifting problem

Your shift lever is connected to a shaft with a gear on the end. That gear drives a vertical shaft, also with a gear on the top end. That vertical shaft runs into the lower unit, where it has a cam on the bottom end. The cam operates a spring-loaded pin, which in turn is attached to the clutch dog. It's possible something has slipped or worn somewhere in that chain. Gear teeth can strip. Shafts can break. Springs can break, etc. It's pretty easy to drop the unit on those motors, so I'd start there and confirm whether the issue is in the unit or up above...
 
T

Turtle61

Recruit
Joined
May 5, 2013
Messages
4
Re: 7.5 Johnson shifting problem

Chinewalker said:
Your shift lever is connected to a shaft with a gear on the end. That gear drives a vertical shaft, also with a gear on the top end. That vertical shaft runs into the lower unit, where it has a cam on the bottom end. The cam operates a spring-loaded pin, which in turn is attached to the clutch dog. It's possible something has slipped or worn somewhere in that chain. Gear teeth can strip. Shafts can break. Springs can break, etc. It's pretty easy to drop the unit on those motors, so I'd start there and confirm whether the issue is in the unit or up above...
Click to expand...

Thanks so much. I will start tinkering with it tomorrow.
 
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