OMC prop shaft seals

[CaptCrunch205]

I just noticed that there is oil on the driveway under my outdrive. I traced it to the seal behind the prop. How hard is it to replace these seals? Do I have to separate the lower unit from the drive? Do I need any special tools? Seems like everything OMC needs special tools. Just wondering what I am in for.

 

[CarTuner]

What year/model drive do you have? The complexity depends on that.

 

[Scott Danforth]

OMC made several different drives over the 41 years that they made outdrives prior to going out of business.

lets start with what do you have?

 

[CaptCrunch205]

I have an 89 Four Winns 205 Sundowner with a 5.0L Ford with an OMC Cobra Outdrive.

 

[kenny nunez]

The lower gearcase uses the same seals, mount bolts and “O”ring as an outboard. Drain the oil, remove the 4 cap screws in the cavity. You will probably need a slide hammer to pull the seal retainer out, after that remove the seals and replace them along with the small “O” rings under the cap screws and the large “O”ring. Clean the housing out and re assemble with some liquid sealer, then re fill with gear oil.

 

[CaptCrunch205]

How tough is the seal retainer? Do I have to worry about it breaking it if it is stubborn about coming out?

 

[kenny nunez]

Most times they came out a lot easier than the Mercruiser ones. Usually a couple slams with the slide hammer was all that was needed.

 

[CaptCrunch205]

So this all got started when I pulled the drive for the beginning of the season. I had a tear in the drive shaft bellows so I replaced that and checked and greased everything and made sure everything was good. Refilled it ran it on the muffs and everything worked fine. Then I noticed it leaking oil from the prop shafts so I picked up the seals and o-rings and was going to change everything today. Drained the oil into a clean pan to reuse. It drained for about 5 min and hen all of a sudden just a stream of water came out and then back to oil. On either side of that clear water the oil was not milky. Obvoiusly the oil is shot, but where would that water come from. I am going to pull the outdrive and look things over. It,s funny because after I ran it on the muffs I let it sit and checked the dip stick to see if I needed to add any oil and it was at the mark so I was good. It was clean oil then too. What other things do I need to check? Thanks

 

[CaptCrunch205]

I moved this to it's own thread.....