OMC 120 Sterndrive problems

[tjmcnutt]

Hello all. Fisrt time on iboat and I have a question to a problem my Captain (Fire) has with his boat. He was out last weekend and was enjoying the weather with his family towing a tube and lost power, I should say that something gave and he pull back on the throttle to "N" and then tried to put in "FORWARD" which engaged and the more power he gave the quicker it acted like it was poping out of gear. Any ideas on what may have gone wrong would be great. Thanks!

 

[WizeOne]

Re: OMC 120 Sterndrive problems

OMC 120 may not mean a lot to a lot of folks here. You should be a little more descriptive, at least with a year model.

That aside, does it 'pop' out of gear or just rev up and loose traction? If so, you either have a spun prop hub or a spun coupler. If what you have is the '87 or later volvo/merc style drive, the coupler is bonded rubber to an outer housing and inner splined core (really just like a prop) Spun couplers usually smell like burned rubber.

If not (depending on the drive style) you may have an out of adjustment shift cable.

 

[futz]

Re: OMC 120 Sterndrive problems

did the boat overheat? if not it's the prop that spun, use some bright fingernail polish and draw a line thru the center of the hub. run it again and see if the line match's up when you pull the boat out.

if it did overheat then could be one of 2 things " i think ".

One this being a stringer drive cause the 120 was never in a cobra drive boat.

It could be the water pump shaft, it stripped out. Or the coupler then the motor got to be pulled to replace that.

So first, the prop, if it's not that, then shafts, easy enough to check, pull the, water pump, then the coupler.