Alpha 1 Gen 2 Drive Leak; Reseal Question

[StevNimrod]

I have a 1994 Alpha 1 Gen 2 (of course I don't have the drive serial number handy). Last year I replaced the input yoke and the corresponding seal since I found a few tablespoons of gear lube in the u-joint bellows. The input yoke was pitted right where the seal rides so I figured that was the fix.

A couple months later, when I went to pull the engine again at the end of last season there was again gear lube in the u-joint bellows and I had noticed some lube loss in the remote gear lube reservoir .

Any idea what's going on here?

Also, is resealing a drive something that can/should be done preventatively or do most people wait until they have water in the drive? There's a guy locally who is reputable and would do a full reseal for a little under $$$. I was going to pressure test the drive soon and see if it holds, which it should since I'm not getting water in the lube.

Which brings me to my final question - I generally like to at least attempt doing things once; is doing it myself feasible for a reseal job or would I spend more in special tools and frustration? For reference on mechanical ability, or lack thereof, I didn't find bellows replacement was as hard as everybody had me thinking it'd be (there were two or three times I walked away for five minutes); it was just time consuming.

 

[Bt Doctur]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

Whats the seal number your using, because the original one is still available under a different number .it`s the double lip seal.

 

[StevNimrod]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

Whats the seal number your using, because the original one is still available under a different number .it`s the double lip seal.

The seal number I used is 26-823894. Are you saying the original seal has a double lip? It was just frustrating to see it doing the same thing in leaking lube!

 

[zbnutcase]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

Do yourself a favor and farm the reseal out to a pro as special tools ARE needed. I have seen DIY reseal jobs leak worse after they were touched!!!! 'nutcase

 

[Bt Doctur]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

26-68493 ,Sierra 18-2003 is what the book shows for GEN II

 

[Don S]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

26-68493 ,Sierra 18-2003 is what the book shows for GEN II

Sorry, but that number is for the 1 drives, R, MR, and Alpha I.

Not the Gen II. He has the proper number for a Gen II, except that the 27- has been removed. It is now 823894 from a Mercruiser dealer.

 

[Bt Doctur]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

That number listed as the replacement using the upper seal kit, Don .
comes back with the same seal number used in both drives
http://ww2.sierramarine.com/sierra/...15

 

[Don S]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

I'm going by Mercruiser parts catalog, not Sierra.

 

[achris]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

26-68493 supersedes to 26-823894... That means the seal designed for the Gen II is now also used in MC1/R/MR/Alpha1. It does NOT mean that the original seal (26-68493) can be used in a Gen II...

Both of these seals are single lip, never have been double. The Sierra kit shows a 26-864319 as part of the Gen II kit. It's a small double lip seal, but I can't find it anywhere in the Merc catalog...

The correct seal to use in a Gen II is 26-823894, as the OP did.... However, if the yoke was pitted where the seal rides and only a new seal is fitted (and nothing else is done), then it will leak again... Only way to fix it so it doesn't leak is to repair/replace the yoke.

Chris.......

 

[Don S]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

Only way to fix it so it doesn't leak is to repair/replace the yoke.

He did replace the yoke. This is from his original post.

Last year I replaced the input yoke and the corresponding seal since I found a few tablespoons of gear lube in the u-joint bellows. The input yoke was pitted right where the seal rides so I figured that was the fix

It's also very possible the NEW seal was defective or damaged. Was the drive pressure checked before putting in gear lube and reinstalling?

 

[achris]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

He did replace the yoke. This is from his original post.

Quite right. I missed that...

It's also very possible the NEW seal was defective or damaged. Was the drive pressure checked before putting in gear lube and reinstalling?

Could also be the 'o' ring. Damaged or the surface it seals on pitted.

Chris.........

 

[StevNimrod]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

'Nutcase,

I figured as much as far as farming it out. Just got to thinking and realized it's really one of those things that, if done incorrectly, tends to result in catastrophic failure.

That said, are reseals ever done as preventative maintenance?

I guess most people wait for milky oil, but after having been there last season with my engine I'd really not like to revisit.

Bt Doctur,

From that link it appears that Sierra 18-2003 crosses to Merc 26-823894, which is the part I used.

Chris,

I replaced the yoke with Merc 46020T (Yoke, Gear End). The originally was badly pitted by the spring that sits inside of the seal itself. I saw this and figured the source of the original leak was nailed.

Don,

Of course I didn't pressure test it . That was before an issue I had with a fresh engine build having a cracked block so I hadn't yet learned the value of testing everything (sometimes twice) before installing it.

I do plan on draining the oil and pressure testing the unit in the next few days.

Lastly, that rear O-Ring (25-70937) was not replaced. I bought it when I bought the seal and yoke, but misplaced it by the time I went to do the seal. I guess I'll know if it's the problem when I go to pressure test.

 

[Don S]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

Just a hint. Orings and gaskets are NOT reusable. If you take something apart that is sealed with a gasket or oring, relace them with new.

Otherwise you end up doing what you read in the blue part of my signature.

 

[StevNimrod]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

That what makes you the "Oracle" and me the "Petty Officer".

And I suppose the local Merc dealer would fall somewhere in the middle.

I called them while I was doing it yoke seal and the advice was "look at it carefully and if it looks okay, then reuse it". Seemed odd because I always replace any gasket or seal, but who am I to question the local Merc place? Actually it was the same advice they gave me today about the seals for the remote oil filter adapter (inspect, reuse if ok) but since they had two on hand I got them anyway.

So should I pull the thing back apart and replace that o-ring, pull it back apart and replace the o-ring and yoke seal (again), or just get the whole deal resealed as preventative maintenance?

 

[Don S]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

If I am going to spend hours of labor to fix a problem for a customer, I'll be damned if I re-use a $3 oring and have to go back through all that labor a second time for free just to save him 3 bucks that costs me a redo and a lot of non profit time.
Your shop is just waiting for you to get fed up with the leak and drag it into them for repair. Then, all they have to do is throw a couple of seals in it and be good to go.

 

[achris]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

Before you do ANYTHING, you should at least pressure and vacuum test it.... You may find that there is a problem elsewhere. Then you won't be going in blind and trying to take out a mouse with a shotgun!

Chris.........

What makes Don an oracle, and you a petty officer, and me a vice admiral? The number of posts here, that's it.... (Don's a bit different, he really IS an oracle )

 

[StevNimrod]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

If I am going to spend hours of labor to fix a problem for a customer, I'll be damned if I re-use a $3 oring and have to go back through all that labor a second time for free just to save him 3 bucks that costs me a redo and a lot of non profit time.
Your shop is just waiting for you to get fed up with the leak and drag it into them for repair. Then, all they have to do is throw a couple of seals in it and be good to go.

That's part of the problem Don; people like you are starting to be the exception, rather than the rule.

Around here all that would happen is the work would get done, the o-ring reused, then when it leaked again they'd say it needs a complete reseal at $900-1200 (at least that's the price the Merc dealer told me when I was picking up parts). That's what happens when you are one of two Merc places in town and deal with people that have a few bucks and varying degrees of time and knowledge to fix on their own.

So I only use the Merc dealer for parts and the occasional question. Otherwise, my normal mechanic is almost an hour away and I'm more than willing to make the drive because I trust him to do honest work and give me non-BS answers to questions. Unfortunately he doesn't mess with lower units so I had to call the Merc dealer about the ring. And we see how well that worked out!

If they're waiting for me to get fed up and quit, they'll be waiting quite a while. My old man has this thing about quitters and even though I'm grown he'd probably still find the vital energy to track me down and carefully place his foot.

 

[StevNimrod]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

Before you do ANYTHING, you should at least pressure and vacuum test it.... You may find that there is a problem elsewhere. Then you won't be going in blind and trying to take out a mouse with a shotgun!

Chris.........

What makes Don an oracle, and you a petty officer, and me a vice admiral? The number of posts here, that's it.... (Don's a bit different, he really IS an oracle )

I have the pressure testing device rigged up on the kitchen counter, five feet from the drive ; as soon as I have some substantial free time I'll get them over to the garage and hook them up. Are you supposed to do P and V on Alphas or just P? I thought I remembered something about only using pressure and never more than about 12-15 psi, and if you do use vacuum it won't hold more than 6 inches but Merc doesn't specify a vacuum test. Maybe I remember incorrectly.

Number of posts and experience! The experience is what I lack so I'm trying to absorb some of you guys'.

 

[achris]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

Pressure test is checking for a seal that will allow oil to leak out. I use about 12-15psi...
Vacuum test is checking for a seal that would allow water to leak in. I usually apply about 10-14" of vac.

On the earlier drives (up to 1991) the shift shaft seal would start to leak at about 6 or 7psi if it was a bit old. Gen IIs don't have the same shift shaft seal...

Chris....

 

[StevNimrod]

Re: Alpha 1 Gen 2 Drive Leak; Reseal Question

Drained the oil; looked good with no discoloration or streaking. Put 12 psi to it and leaked down to 5 psi in 20 minutes.

Of course I failed to bring anything to spray around the drive to help find the leak so I get to do it again tomorrow.

I did lift the drive shaft such that I could see the rear seal (where it rides on the input yoke) and it seemed that seal itself may be defective. I'll double check tomorrow.