7.5hp Johnson Sea Horse

[tallcontrol]

I have a 1982 7.5hp Sea Horse long shaft that seems to buck when it is at full throttle. The buck is loud and occurs about every 20 seconds. I have tried to simulate it by hitting the kill switch but didn't sound the same. It seems like I am hitting a rock. I have never felt it at low speed. Any suggestions on this problem?

 

[o/b tech]

Re: 7.5hp Johnson Sea Horse

Sounds like the clutch dog is not staying locked to the forward gear at high speeds. This starts to happen when the teeth start to round off. It may be time to have the gearcase looked at.

 

[tallcontrol]

Re: 7.5hp Johnson Sea Horse

I am new to boat mechanics and am wondering when you say gear case, where it is and is it the same an lower unit? Should I attempt to look at it being fairly mechanically inclined to other fields?

 

[o/b tech]

Re: 7.5hp Johnson Sea Horse

Yes the gearcase and lower unit are the same. If you haven't tackeled anything like this in the past, it might be better if a service shop looked at it as they can also give you an overall assessment of the motor. Hope this helps.