Evaluating used I/O's before purchase

[fishnfiend]

Have searched on this topic, and find bits and pieces. <br /><br />Looking at several late 70's to late 80's I/O's (ski/runabout) but need to know what to look for in the drivetrain. Can evaluate general engine condition fine, do compression tests, look for leaks, etc., but don't know how to judge the outdrive unit condition. Own three Volvo cars and do all maintenance myself as well as all work on my E'rude 40, jeeps, etc.<br /><br />Have read that OMC's of this era are to be avoided, although there are lots of them out there still running. Volvo's are bulletproof but parts may be harder to find and pricier. Read that Merc's ("Black anchors") may break more but parts are common and cheap and it's easy to find mechanics.<br /><br />What would discriminate an outdrive in good shape from one about to fail? What are the most common failures of an outdrive? Are there any of the I/O's of this age the uninitiated should absolutely stay away from?<br /><br />Thanks for any information.

 

[fishnfiend]

Re: Evaluating used I/O's before purchase

Bump<br /><br />Hope this topic isn't too worn out for some interested expert out there. Sorry if it gets asked alot, but if so, I can't seem to find the right search terms to capture it.

 

[Bondo]

Re: Evaluating used I/O's before purchase

Are there any of the I/O's of this age the uninitiated should absolutely stay away from?<br />

Ayuh,..... As you Already Know,...............<br /><br /> OMCs.........................................<br /><br />Stick with either a Mercruiser,....... or Volvo...........<br /><br />There were some Odd-Ball drives such as a Short Lived Chrysler drive....And I've seen Eaton drives,......<br />No Support for Either of these.....

 

[Phantom17]

Re: Evaluating used I/O's before purchase

Look for the obvious milky fluids, shifting properly, metal shavings. Other than those basics, I'd be interested in hearing any tricks

 

[Lou C]

Re: Evaluating used I/O's before purchase

First find a good sterndrive mechanic<br />then pay them to check it out if you can.<br />If that is not possible there is a lot to check--engine--does it start and run properly, does it overheat, what about oil leaks/unusual noises, when were the manifolds/risers last replaced?<br />Drive, does it shift properly into and out of gear? A dog clutch drive (Merc Alpha, OMC Cobra) will clunk some going into drive but it should not be excessive. And does it come out of gear easily? Does it jump out of gear under load (possible expensive repair, worn clutch dog/foward gear). Does the tilt and trim work and not bleed off when left up, and does the steering system work smoothly? <br />As you can see there is a lot to check, more so than with an outboard.

 

[fishnfiend]

Re: Evaluating used I/O's before purchase

Thanks, gents. As they say, forewarned is forearmed. I'm in a much better position now, once again, for having read The Board.<br /><br />Lou, can these units be put into gear while running on muffs on the trailer, or do they need to be in a lake?

 

[rodbolt]

Re: Evaluating used I/O's before purchase

ya need to test run it for at least an hour with a 30 min run in the reccomended operating range.<br /> check the maint history on the manifoilds, risers, shift cable if applicable, check the maint history and condition of all drive bellows and any rubber exhaust components. look carefully for shade tree tracks.<br /> carefully check prop condition, its an indicator of whacking the bottom.if its not a stringer drive unit place the outdrive level and hop up and down on it while an observer looks for any transom flex, pull the drive on applicable models and inspect the shaft alignment and spline and gimbal bearing.<br /> ask for the regular maint reciepts. most of the maint is hourly OR a time period. if not done either deduct or run.

 

[Lou C]

Re: Evaluating used I/O's before purchase

you can run it in gear on the water hose (take the prop off for safety) but you can't really check for proper shifting unless it is in the water and the resistance of water is against the prop. Some units will shift ok on land and stiff in the water. So water test it like rodbolt says and do check to see if they maintained it. Otherwise the repair costs can add up real fast.<br />As an example on mine which is moored in salt water, every year the mechanic removes the drive, pressure tests it checks the bellows, gimble, ujoints, and shift system. I do the winterizing and tune ups myself. I leave the drive work to the pros!