OMC Motorized engine mount...huh??

[seabob4]

My buddy calls me yesterday, has a "project" OMC 2.5L I/O with what appears to be the front mount with a motor on it.  He's confused, I'm confused.  Must be something else...

So this morn I go over and look at it.  Sure enough, a trunnion motor mount like on Mercrusiser's...but with a motor and gear drive like it can lift the whole front of the motor!!  WTF!!

So he brings his laptop out, I find a P/N, it's for a trim bushing...hmmm.  So google "Stinger trim and tilt", and, voila!!  Seems the Stinger outdrive was notorious for eating gears and bearings when trimming, so rather than fix the problem, OMC offered an EXPENSIVE upgrade that literally trimmed the motor and drive as one...tilted the whole shooting match!!  

You guys ever seen this??

[fitz73222]

Bob,
That was the standard trim system for old OMC electric shift stern drives from '64-'77.

[fitz73222]

Remember the huge transom hole for the rubber bellows? That flexed as the engine went up and down. The drive unit was bolt directly to the engine and not bolted to the transom like MC or Volvo. The only thing between you and the bottom of the deep blue sea was that rubber bellows. Seen lots of them get cut from barnacles since you couldn't bottom paint the rubber bellows. Trim the engine up and down with a load of barnacles on the bellows and start a leak! I think the Cobra was the first conventional transom plate design with more modern trim ram system for OMC circa '84 ish?

[Bergertime]

I remember those... used to see them up on the lakes when I was a kid.  How unnerving would that be being offshore with that rubber bellows being the only thing from keeping you from swimming! What a nightmare!

B

[seabob4]

Well thank you fellas, now I feel like a newbie!!  Honestly, I have always dealt with Mercruiser or Volvo, never OMC.  Apparently my buddy AJ hasn't either, as he was just as stumped as I was.  I told him the owner needs to dump the OMC and go with an Alpha, but jeez, is that hole in the transom big!!

[GoneFission]

Muskrats would chew on the OMC bellows sometimes in fresh water - and when they chewed through the rubber -  oooops!   :x   I know of a couple boats that sunk at the dock due to "muskrat intrusion."  

[Aswaff400]

our old '81 cobia 24 we used to have had an omc stringer drive, that rubber boot was scary... when my dad rebuilt the boat, a volvo cobra drive was mated to a new 350 mercruiser...