Johnson 88 spl lower drive?

[stratman]

Just bought a boat with an '89 Johnson 88 hp spl. Taking it in for a check up, but its 2 weeks before anyone can get to it. Occasionally, the boat will jerk like its hitting a stump while going down the lake. It seems to be getting more frequent. It happens very quickly and causes a fairly violent jolt in the cabin. Is this a classic sign of a lower drive gear problem?

 

[tashasdaddy]

Re: Johnson 88 spl lower drive?

it is the classic symptom of the clutch dog gone bad. prepare for a lower unit rebuild. these gear have very square teeth, when they get worn, the jump out of gear, and back in on the next revolution.. 99% of this is cause but poor shift habits, and the engine idling too high. you should shift with a quick deliberate motion. not the old let's easy it into gear, and listen to the gears mesh. while you are listening to those gears mesh, they are wearing off the corners, or the clutch dog and forward gear. i have a 88 88spl. so you problem boils down to previous operator error, but you now know how to avoid it when fixed. advise not to use the boat until repaired.