Alpha One Upper: vertical driveshaft lower oil seal

rocky388

Seaman Apprentice
Joined
Jun 10, 2013
Messages
39
Hello,

I've spent the better part of 2 days searching for more information regarding the oil seals on my alpha one outdrive. It all started as I was replacing my impeller part of my pre-season maintenance. I pulled the lower half off, and looking up into the opening where the vertical driveshaft goes into, I saw the o-ring that goes on the driveshaft (which I'm not entirely sure should be on there, as there is no groove on the driveshaft where an o-ring would sit onto?) So I picked that out, and upon further inspection I found another "o-ring" with a spring around it. Through research I, possibly incorrectly, determined this to be the lower oil seal.

Based off this exploded view (Sterndrive Exploded Views A : MerCstuff.Com), I ordered parts:
29: 26-96503
30: 26-32511


I have pictures to help when I figure out how to attach them.

My questions are: Did I order the correct parts? I'm figuring that I only really need part 29. How do I remove, and install these oil seals? It seems like there's a metal piece pressed in right now, will I have to pry that out with a screwdrive, and press in the new replacements?

I should ad, there was not any water in the outdrive oil, and there doesn't appear to be any signs of wear or anything unusual....aside from the broken exhaust butterfly valve I found behind the shift shaft :facepalm:

Thanks
 
Joined
Mar 27, 2010
Messages
3,008
Re: Alpha One Upper: vertical driveshaft lower oil seal

the bottom seal is replaced from the bottom. The upper seal has to go in from the inside which requires dis-assembly. It's common for the lower to fail. If the upper one looks good, I'd just do the lower unless you want to get into it.

Just pop out the lower one and tap in the new one. I use a seal puller to remove....
 

rocky388

Seaman Apprentice
Joined
Jun 10, 2013
Messages
39
Re: Alpha One Upper: vertical driveshaft lower oil seal

So I did order the correct part? I'll work on prying out the thin metal piece that seems to be pressed in if that's the case.

As far as the o-ring that comes with the impeller kit, should that go on the vertical driveshaft a few inches from the top, despite not having a groove for said o-ring?
 

rocky388

Seaman Apprentice
Joined
Jun 10, 2013
Messages
39
Re: Alpha One Upper: vertical driveshaft lower oil seal

20140416_132624_resized.jpg

pry out the thin metal piece that appears to be pressed in?

20140416_155229_resized.jpg

and this is the piece I found laying in there. This is what I'm assuming is part of that oil seal.
 
Last edited:

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,111
Re: Alpha One Upper: vertical driveshaft lower oil seal

you can use a long flat blade screwdriver to remove it and a 1/2 inch drive long extension and the correct size socket mounted backwards as a driver head.
 

muc

"Retired" Association of Marine Technicians...
Joined
Jul 7, 2004
Messages
2,064
Re: Alpha One Upper: vertical driveshaft lower oil seal

Throw the O-Ring away, you don't use it.
 
Joined
Mar 27, 2010
Messages
3,008
Re: Alpha One Upper: vertical driveshaft lower oil seal

Yes those numbers look correct according to that diagram. That thin piece is the rest of the seal.
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Alpha One Upper: vertical driveshaft lower oil seal

I replace that lower seal in the upper housing every time I change an impeller. I NEVER put the 'O' ring on the top of the lower drive-shaft...

The seal is very easy to replace. Just flick it out with a screwdriver, pocked in through the exhaust passage in the upper housing.
And from your photo, the upper housing is still on the bell-housing, you are going to need to remove it...

HTH,

Chris......
 

rocky388

Seaman Apprentice
Joined
Jun 10, 2013
Messages
39
Re: Alpha One Upper: vertical driveshaft lower oil seal

Thanks for all the replies.

achris, my drive is still on the bell-housing. I was hoping to do this job without removing it, however I did order the bell-housing seal kit just incase I can't.

I just popped the old oil seal out - what's left of it anyways. I'm just waiting on the arrival of the new.

Should I be able to see the second oil seal? After removing the damaged one, it doesn't look like there was anything above it aside from the pinion that the vertical drive shaft goes into.

20140416_173245_resized.jpg


Basically..does this look correct aside from the lower oil seal missing?
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Alpha One Upper: vertical driveshaft lower oil seal

That looks correct. The upper seal is larger, and without removing the upper drive-shaft you can't see it... If there's no oil dripping down, it's there... ;)

If you managed to get the old lower seal out without removing the upper housing from the bell-housing, then you should be ok to put the new seal in.... But.... you haven't check the engine alignment, greased the unis, checked the bellows for water, or oil leaking from the front seal in the upper housing.... This is why it's recommended to remove the complete drive when changing the impeller, so all these items, which are ANNUAL service items, can be checked.... Just saying...

Chris........
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
Re: Alpha One Upper: vertical driveshaft lower oil seal

The work is easier to do when the drive is off. Build a stand on casters. It makes it super easy. I used to do my Alpha every other year (only about 15 hours a year run time). With the bravo I have to do it every year for garage fitment.
 

rocky388

Seaman Apprentice
Joined
Jun 10, 2013
Messages
39
Re: Alpha One Upper: vertical driveshaft lower oil seal

Thanks guys. I decided to do it properly and pull the drive.

I had a pinched o ring going to the water supply hose, and the drive shaft big o ring was also pinched. Due to these issues,I replaced the gimbal bearing, and pulled the drive shaft out of the upper unit (broke some tabs off of the retaining nut that holds the driveshaft in during the process) to do the u joints. Honestly, neither were in bad shape..a slight rust on the u joints.

My plan is after trying, and fighting with the u joints, I'm going to have a shop press them out and new ones in. Gimbal bearing is already done. I'll have a local marina tighten that retaining lock nut (cheaper than buying the tool myself I would assume). Everything else looks good, no pitting or corrosion. There was no water in my outdrive oil, so I think that must mean all those bearings and seals were not exposed to water.

My question is..is there anything else to be mindful of? Anything else I should replace? I'd like to avoid breaking into the driveshaft.
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
Re: Alpha One Upper: vertical driveshaft lower oil seal

Check over the bellows really well. The driveshaft bellows and shift cable bellows are most important. The exhaust bellows can fail and not hurt anything. You may want to replace the shift cable if there was any sloppyness getting into neutral.
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Alpha One Upper: vertical driveshaft lower oil seal

Why did you pull the drive-shaft to replace the unis? You can just whack them out and 'press' them back in with a standard vice or 'G' clamp without having to pull the shaft out of the housing....
 

rocky388

Seaman Apprentice
Joined
Jun 10, 2013
Messages
39
Re: Alpha One Upper: vertical driveshaft lower oil seal

Bellows were new last year, they're still in very good condition. Neutral doesn't feel sloppy.

I pulled the drive because the back u joint was blocked from being pressed out by the tabs on that retaining locknut. That's how I broke a tab, and at that point decided to pull the drive and replace that locknut. I tried the c clamp and socket method, and I rented a u joint press tool, nothing was sitting flat on the joints without slipping off as I tightened it to press them out.

Thanks.
 

rocky388

Seaman Apprentice
Joined
Jun 10, 2013
Messages
39
Re: Alpha One Upper: vertical driveshaft lower oil seal

Pulled my drive for impeller corder to Lheck also. Thnx for help everyone so far. As per achris advice ordered lower oil seal. When I installed it I drove it all the way in with the grooved side in until it mated with circular structure about 1-1.5 cm below surface. Wrong thing to do! Gonna order another seal and not use the one I drove in too far. Couple questions please: 1)cant tell from Seloc manual which side of seal goes in first--side with groove or flat side. Thought Youtube video of seal change showed grooved end in first. 2)what is coiled wire o-ring in the grooved area of seal for? Doesn't seem to stay in place. Old one was broken and up insidethe assembly. Whats easiest way to degrease area for insertion of seal with Loctite? Which Loctite to use? Thnx again.

I could be wrong, but once that o-ring gets removed from the carrier that it's installed in, I would think it's no good anymore. Or at the very least needs to be put back, which looked nearly impossible. Make sure when you install the seal, you have a big enough socket that you're hitting the carrier, and not the o-ring. The flat side of the carrier faces out, if that makes sense.
 

karbine98

Cadet
Joined
Mar 17, 2014
Messages
29
Re: Alpha One Upper: vertical driveshaft lower oil seal

In the picture of the seal above looks different than the ones I've received. My seals have groove running around the underside with coil spring inside. The one above looks like it has a groove running around the outside. Any clarification would be appreciated. Thnx, Greg
 

rocky388

Seaman Apprentice
Joined
Jun 10, 2013
Messages
39
Re: Alpha One Upper: vertical driveshaft lower oil seal

In the picture of the seal above looks different than the ones I've received. My seals have groove running around the underside with coil spring inside. The one above looks like it has a groove running around the outside. Any clarification would be appreciated. Thnx, Greg

Are you talking about my picture? If so, that's because my picture is of the o-ring removed from the seal. I took that picture because I found that o-ring with spring laying in the drive and needed help identifying it. A brand new seal will have the o-ring with spring already installed onto the "carrier" for lack of a better word. It's all one piece to make it a seal.
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Alpha One Upper: vertical driveshaft lower oil seal

That 'o' ring you are referring to is the inner lip of the seal. It's broken, replace it.
 
Top