OMC outdrive (NOT Cobra) questions, satring with Model Number

[Printeric]

HI, every one, from a newbie!
I recently picked up a Sea Sprite Mark III Continental (1984) with an OMC I/O. This is my first boat. I have used boats before, but never with an I/O. The model #number on the engine, 990234E1, Identifies it as a 1977 120HP. It runs well (IF I jump start it), but as you can imagine, the ol' girl needs some fixin'. Besides the battery, the Bellows has tears in it, and the ball gears need replacing. There is a model number on the Outdrive, 983586, but I can't seem to find any info when I search for that number. I also could use a little help with terminology, as in Upper, Lower and Intermediate sections. I can guess that the lower Section is where the prop is, up to where it bolts onto what I suppose is the upper section, but what is the intermediate section, i.e. where does it start and end? Also, is a transom seal the same as the bellows, or are they two different parts. I'm sure I'll have other ?'s but that's enough for today!

Thanx in advance to anyone who can help!

 

[southkogs]

Re: OMC outdrive (NOT Cobra) questions, satring with Model Number

I'm having trouble figuring out what you've got there ... numbers aren't matching up to anything I can find. In fact when I started with the first number, a COBRA came up and I didn't think they made one in '77.

Pictures will help determine what Stringer drive you have. A '77 OMC 120 should be an electric shift outdrive married to a Chevy 152 Inline 4 (I think '77 was the last year for electric shift). You don't have bellows on that drive ... you have a boot (which you already know you need to replace). You need to get a manual once you figure out what you have ... there used to be a PDF floating around the web, but the links have changed. You can find some information HERE and HERE.

In '84, the Stringer was probably a 400 series. A hydro-mechanical shift. If you've got an '84 boat with a '77 drive ... you may have something of a "Franken-motor." Like I said, pictures may help out.

As far as intermediate, upper and lower - this might help:

 

[Howard Sterndrive]

Re: OMC outdrive (NOT Cobra) questions, satring with Model Number

983586 isn't a 1984 drive either. all 1984 drives start 982...

those number are impossible to reverse reference - there's no logic to the number system, and the only place vertical drive numbers are reference outside the factory is in the "all models" service manual for a particular year (I have the 1984 one and it's not in there). Also, that upper gearbox where the tag is affixed, could be rebuilt to a different gear ratio some time in the last 25 years.

lower = prop end
upper= where that tag is riveted on
intermediate = inside the hull attached to the engine

Is the exhaust through the propeller on your drive?

 

[Scott Danforth]

Re: OMC outdrive (NOT Cobra) questions, satring with Model Number

you may have to post pics.

by the way, the prices for the OMC parts will surprise you if you havent already looked.

 

[Printeric]

Re: OMC outdrive (NOT Cobra) questions, satring with Model Number

Thanks everyone for the info... I'll try to get some pix up soon. The exhaust is Not thru the prop, but above it in the upper unit. I have to go to work.. night shift.. will try to get more info tomorrow.

 

[Howard Sterndrive]

Re: OMC outdrive (NOT Cobra) questions, satring with Model Number

The exhaust is Not thru the prop, but above it in the upper unit.

then it's 1977 or older.

looks like the ownership is the screwy part. If your boat has a hull ID number branded into the fiberglass (starboard side of transom just below rub rail), check it - the last 2 digits are the year.

 

[Printeric]

Re: OMC outdrive (NOT Cobra) questions, satring with Model Number

Hi, I'm going to try to upload some pix I took this morning.

Hope this helps. I have some others, but the files are too large to upload.
By the way, you can see there is some damage to the lower unit... is that a problem? I can guess I will need to replace the prop for efficiency's sake, but can I use it safely for now? What about the ball gears? Just so you understand, I won't be using the boat much this year even if I get it fixed up... but I would like to get in a few runs before the lake freezes!

 

[Howard Sterndrive]

Re: OMC outdrive (NOT Cobra) questions, satring with Model Number

The exhaust is Not thru the prop, but above it in the upper unit.

your exhaust is through the prop in the pics posted
see how the propeller is open in the center

drive pictured is a late 1984 or 1985 mechanical shift 400 series (I think - when you change the prop count the splines - 13 = 400, 15= 800)

If your engine is original, it will be painted silver like the drive. If the engine is blue, it has been replaced. OMC switched from blue engines to silver engines mid 1984

 

[Printeric]

Re: OMC outdrive (NOT Cobra) questions, satring with Model Number

your exhaust is through the prop in the pics posted
see how the propeller is open in the center

drive pictured is a late 1984 or 1985 mechanical shift 400 series (I think - when you change the prop count the splines - 13 = 400, 15= 800)

If your engine is original, it will be painted silver like the drive. If the engine is blue, it has been replaced. OMC switched from blue engines to silver engines mid 1984

Just shows what a Newbie I am:redface:! The engine IS blue, I had a pic but couldn't upload it. No question its a 120 HP 1977, but from what you're saying, the outdrive is OEM for the boat.

If your boat has a hull ID number branded into the fiberglass (starboard side of transom just below rub rail), check it - the last 2 digits are the year.

The last 2 digits are 84.
So... what are the holes in the upper unit that I Thought were exhaust...water return I guess?