Johnson 88hp Clunk Problem

[magic8ball]

I have a Johnson SPL88 V4 on a pontoon boat. Just recently docked for season 2 weeks ago. When driving down river boat runs fine then all of a sudden I get a thump or clunk/bang sound that shakes whole boat like I hit a log or something. If I back of throttle to slow speed it does not seem to do as often as when I am at full throttle. It will do this about every 100 yards or so. Did not do this last season and motor was never taken off or changed in any way, just normal winterizing. Any help or suggestions?

 

[tashasdaddy]

Re: Johnson 88hp Clunk Problem

hate to be the one thats breaks this news, but the lower unit needs to be rebuilt. sounds as if the clutch dog, or forward gears tooth have worn off., the only other thing to try is release the shift cable at the engine, and shift to forward manually. the shift cable may have stretched and not putting the lower all the way in gear. if this doesn't solve the problem don't run the motor other than to trailer it. heres a link to the engine diagrams.
http://www.evinrude.com/en-US/Accessories/Literature/

 

[magic8ball]

Re: Johnson 88hp Clunk Problem

Is this hard to fix? Any special tools needed? I did rebuild the power head myself so I am fairly handy in the garage. Shoul all working parts need replaced or just worn ones.