Sterndrive swap

[mereed]

Didn't see this exact question...will any 190hp OMC sterndrive unit behind a ford 302 be an exact or close enough swap?
I've located a used one, and need info before I pull the trigger.
Also, does "stringer" refer only to the tilt/trim feature built in on a '77 OMC boat?
Thanks for any and all info. Michael.

 

[Bondo]

Ayuh,.... The Stringer drives ran from OMC's beginin' up to 'bout '85/ '86, when the Cobra came out,....

'n No, All stringer drives are Not the same,....
There's the ole electric shift stringer drives, the hydro-mechanical stringer drives, 'n the full mechanical stringer drives,....

Stringer drives refers to the driveline mountin' to the hulls stringers, not the transom, nor it's trim/ tilt systems,....

 

[mereed]

Thanks Bondo, mine is electric shift. My understanding is they changed to mechanical in '78 or '79.
The used one in question doesn't have the id tag anymore, but since hp ratings changed in '78, would I be safe trying it, or is there another way to id it? The motor and sterndrive look identical to mine, except a different make of boat.
Thanks again, Michael.

 

[southkogs]

Welcome aboard.

Best thing for you to do is ID the Stringer. Inside the engine bay, typically on or near one of the motor mounts (mine was on the rear, starboard mount) there's a tag that will have an ID on it. If you're a true '77 electric shift, you've got the last iteration of them. A '78 wouldn't be electric shift, it'd be hydro-mechanical. I'm not very familiar with that shift system, but most (I believe) would say if you're not going to stay electric shift jump the hyrdro-mechanical and go straight to the mechanical shift models ('80 - '85).

 

[Scott Danforth]

OMG stringers

electric shift until '77
hydro-mechanical shift from '78-'81
mechanical shift from '82-85
any '86 stringers are left over '85's

the only thing that fits in an OMC hole is another OMC unless your redoing the transom/stringers/hull. then you can fill that giant hole and put a modern (Non-Ford / Non-OMC) driveline in the boat.

 

[mereed]

Thanks guys, Southcogs I'll look for that id tag before I buy the parts boat.
For the record, I've had my Webbcraft for almost 20 years, replaced the sterndrive 3 years ago, now it looks like the upper unit stripped out on me about midnight last Sat. Found an experienced OMC mechanic who says he'll rebuild the upper for $1000.
Or I may swap the whole sterndrive out myself and take a chance on another used one...not sure if it's worth the risk!
Thanks again, Michael.

 

[southkogs]

Is it your upper gear case that is shot or the lower? You can probably find the upper reasonably easily. Is it by chance the drive shaft that's stripped? (kinda' common)

 

[mereed]

Haven't had a chance to inspect yet. Was told I may be able to tell upper or lower by inspecting oil in each. The boat is garaged two hundred miles from me, so I can't check things out in my off hours. But I have made a bunch of phone calls and Internet searches!
Would one need to tear down upper and lower to replace drive shaft?

 

[Scott Danforth]

you cant tell if the driveshaft splines are stripped until you pull it apart. and yes, it requires a tear-down, re-seal, re-shim, etc.

 

[mereed]

I have an old 225 hp complete sterndrive unit, with the external steering bracket. If I remember correctly I didn't use it last time because it has a taller overall height, and supposedly different gear ratios. Any one have info on that one compared to mine?

 

[southkogs]

Sorry - I meant the lower drive shaft. You shouldn't have to tear the gear case down on that one, but you do have to separate the upper and lower gear cases.

Upper gear case on your 190 should be 21:19, and the upper on the 225 should be 21:16. I don't know enough about gear boxes to know if you can re-prop your way out of that difference.

 

[mereed]

Ok, no visible metal shavings in oil, no discernible clunk when trying to go into gear, when increasing rpm a shrieking noise ensues.
Pulled complete unit and will turn it over to qualified OMC mechanic with all the extra parts and pieces I can come up with.
My time may be better spent making the money to pay him!
Thanks for the info guys. And I do feel kinda dumb about the stringer question...it seems pretty obvious now, lol.