Jolt with shake,clunk feel 2.3L OMC

[OMCEd]

My 89 OMC 2.3L has a sudden jolt with hard vibration to the boat at all RPMs except idle/no wake speed. Feels like someone his hitting the boat with a bat. Like a "clunk" every 20 seconds or so. I replaced my Pertronix II with point ignition and had no change. Engine is constant and does not loose rpm. Does this with ESA disconnected. I am guessing my LU dog teeth are slipping? When I put in gear and hand turn prop there is positive lock. Thank you for any help. Ed

 

[bradb]

Re: Jolt with shake,clunk feel 2.3L OMC

Yes, your dog clutch is slipping caused by a worn or mis-adjusted lower shift cable. You are going to need to replace both the cable and the dog gears.

 

[airdvr1227]

Re: Jolt with shake,clunk feel 2.3L OMC

OMC Cobra Sterndrive Tech Info Required reading for OMC owners.

 

[OMCEd]

Re: Jolt with shake,clunk feel 2.3L OMC

Thank you Brad! Do you think I have a chance to adjust this out at the shift cable inside the outdrive? The engine side red cable is set per manual. Cable does not bind. Shifting feels like engagement is equal throw of the shifter forward and reverse.

 

[OMCEd]

Re: Jolt with shake,clunk feel 2.3L OMC

Thank you Scott!

 

[bruceb58]

Re: Jolt with shake,clunk feel 2.3L OMC

I would definitely make sure the cable is adjusted properly before replacing the dog gears assuming the cable isn't history. The problem is knowing if the cable is still good. Tilt the drive up and look at the housing where it enters the drive. That is where the cable housing usually fails.