Part Identification and Schematic Help Needed

[hosejockey23efd]

Hello,
I have a 1988 OMC Cobra outdrive. On the upper gear case on each side is a sticker or Medallion. While inspecting the boat for this season I noticed that the left medallion was gone and what appeared to be a plug was exposed. Around the plug are the paint had flaked off like heat or something hot leaked out around the plug. My instinct told me there must be a bad gasket or O ring behind it. I took the plug out and now what ever was on the inside of the housing that has the threads in it to hold the plug in place seems to have dropped out of sight. What does this plug do? How do I find the missing treads? Ever parts diagram I find only shows the medallion and doesn't mention or show the plug. Please help me if you can. Thank you in advance for any help.

Jerry

 

[hugh g]

Hello,
I have a 1988 OMC Cobra outdrive. On the upper gear case on each side is a sticker or Medallion. While inspecting the boat for this season I noticed that the left medallion was gone and what appeared to be a plug was exposed. Around the plug are the paint had flaked off like heat or something hot leaked out around the plug. My instinct told me there must be a bad gasket or O ring behind it. I took the plug out and now what ever was on the inside of the housing that has the threads in it to hold the plug in place seems to have dropped out of sight. What does this plug do? How do I find the missing treads? Ever parts diagram I find only shows the medallion and doesn't mention or show the plug. Please help me if you can. Thank you in advance for any help.

Jerry

You need to pull the drive & split it to get at the pieces that have dropped into the lower unit. That's the only way to retrieve them. You're not the first Cobra owner that that has happened to. I think that plug is part of the casting process from the factory. It serves no purpose other then to agravate owners who make the mistake of removing it & then having to tear their drive apart to get the damn thing back out of their lower unit.

 

[dubs283]

You need to pull the drive & split it to get at the pieces that have dropped into the lower unit.

pull the drive, yes. do NOT need to separate the halves

there is a piece of square aluminum stock with a threaded hole the plug will screw into. you need to hold the piece of aluminum in place while installing the plug.

the plug is there to drain any water that may have been trapped inside to prevent freeze damage to the cavity, just crack the plug to drain, or loosen the drive mounting nuts and allow the water to drain. either way is apropos

 

[hugh g]

pull the drive, yes. do NOT need to separate the halves

there is a piece of square aluminum stock with a threaded hole the plug will screw into. you need to hold the piece of aluminum in place while installing the plug.

the plug is there to drain any water that may have been trapped inside to prevent freeze damage to the cavity, just crack the plug to drain, or loosen the drive mounting nuts and allow the water to drain. either way is apropos

Idk. On my 3.0 there was a plug I would unscrew when winterizing to drain water from the cavity. It did NOT have an OMC medallion covering it. Maybe the OP can post a pic of what part he's asking about.

 

[PITBoat]

There's a YT video of this - "the never remove plug" is part of the title. Don't know if the guy's info. is right or not, but he seems to be covering what you did.

The drains are all on the part the drive attaches to (pivot housing?), one on the left, 2 on the right.

 

[Lou C]

Correct, you never have to remove that plug (that was formerly under the medallion) to drain water, all that is accomplished by removing the plugs on the pivot housing, one on port side (that always should drain water from the water passage in the drive and the raw water hose going through the transom up to the thermosat housing).
The ones on the starboard side, don't usually at least on mine, the top is a vent and the lower one goes into the pocket where the shift bellcrank lives. You don't want water in there at all. I keep that area packed with Triple Guard Grease.

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On the earlier parts diagrams they didn't show a break down of these parts but the later ones do, this is what should be there, keep in mind here they show the parts on the starboard side when in reality they are on the port side, there is no hole on the starboard side.

 

[hosejockey23efd]

Thank you all for the great help. PITBoat that YT video covered my problem. What a messed up design. Lou C. thank you parts diagram. That shows a great view of the pieces. I wouldn't have even known there was a plug there that shouldn't be removed if the sticker/medallion wouldn't have come off. I have had this drive off before and t was a pain in the tuchus. Think I will take it to a shop and get it fixed and serviced for the season. Thank you again everybody and remember to put the plugs in before launching.

Jerry

 

[jerryjerry05]

Idk. On my 3.0 there was a plug I would unscrew when winterizing to drain water from the cavity. It did NOT have an OMC medallion covering it. Maybe the OP can post a pic of what part he's asking about.

DIFFERENT plug!! Yours is the tiny one by the bellcrank.

 

[jerryjerry05]

Just get a plug from any auto parts store and screw it in.

 

[PITBoat]

So doddling around, I found that the guy with the YT video had a 2nd one where he shares an idea how to get the rectangular nut back in there w/o taking the drive off. Again, Idk if what he's suggesting is correct.

The comments for the video(s) were interesting too - one guy said that part (nut) ended up in his PS cooler. Another said there's something else that goes with it. You probably can tell that from Lou's diagram though.

It's funny, I'm missing the Cobra head on that side of my drive too...

 

[hosejockey23efd]

So doddling around, I found that the guy with the YT video had a 2nd one where he shares an idea how to get the rectangular nut back in there w/o taking the drive off. Again, Idk if what he's suggesting is correct.

The comments for the video(s) were interesting too - one guy said that part (nut) ended up in his PS cooler. Another said there's something else that goes with it. You probably can tell that from Lou's diagram though.

It's funny, I'm missing the Cobra head on that side of my drive too...

Good Morning ,

Sorry for taking so to reply. Watching the YT videos I can't figure out how they retrieved the parts without taking the drive off of the boat. Looking at the parts diagram there should be a rectangular nut and spring washer that disappeared when I turned the plug out. The guy that had the nut in other areas must have been using the boat when the plug came out. This plug and its set up kind of reminds me of a frost plug in the side of the engine block couple with a drain plug in it. Looking at the plug area on the drive case it appears that some hot water worked its way out from around the edges of the retaining cup causing the sticker to fall of and the paint to peal. I am guessing that I maybe didn't get it winterized good enough once and that retaining cup was loosened some. I am telling myself that even though the drive needs to come off of the boat that I will be fixing a smaller problem before a much bigger and costly one happens. Checking with local repair shops it would be about a month before the boat would be ready to get back in the water. To help keep peace in the house I ordered the few parts needed to replace those parts and will be doing it myself. If just the sticker was gone I wouldn't think much of it but seeing as the paint has pealed around it, that's when I figured the retaining cup should get replaced. It will be next week before the parts come and I get things worked on but will put up a reply once I get it done. Thank you again for your help and time with this project.

 

[Lou C]

I've owned mine 19 years. The medallion was long gone when I got it. Because I had the factory shop manual from the beginning, I never made the mistake of unscrewing that while winterizing lol. Never had a problem with it.
You don't have to take the drive apart, just have to take it off, which is a normal part of I/O maintenance once a season anyway. Yes its a pain sometimes but if you never do it, you will regret it one day. If you want to maintain one of these you need:
factory shop manual
drive jack
alignment tool
in addition to normal hand tools, sockets etc. I like OMC/Evinrude gasket sealer for threads on any threaded fasterners, it keeps them from seizing up even in salt water. Permatex Aviation can be used as a substitute.