Alpha 1 Upper unit Drive Shaft seals

otgdy · Mar 11, 2012

I pulled what I believe is the top drive shaft seal and found that the housing around it is partially broken away.
Attached is a picture of the area and a parts breakdown. From the breakdown it looks like there are 2 seals and a
spacer/shim in this area (12,13,14). I only saw one seal. Am I reading this correctly ?

I put a new seal in the housing and found the break in the housing extends down below the seal and will leak.
Can I use Permatex, right stuff or JB weld in this area and have it hold? Looks like it is going to be a bear to clean
it up enough to have anything hold.

Are there really 2 seals in there ? If yes how are they inserted ? one facing up one down ? How do I do the spacer ?
(i.e. what thickness etc ).

Any input would be appreciated !

Thanks
OTG

Fishermark · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

The upper seal is for the gear oil - the seal / area you have pictured is to keep water out of the driveshaft area - where it couples with the upper drive. I would think you could easily get away with coating the area with JB Weld after installing the new seal. It doesn't seal out the oil - just the water as I mentioned.

Fishermark · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

Just as a follow up - the last drive I worked on (on my dad's boat) the seal you mention was deteriorated so bad as to be non-existent. Here's what the drive looked like:

And here is a comparison of the old "seal" i removed next to the new seal. (The size difference is an optical illusion) :

Not a good idea to let it get like that of course

.... but there was not any problem with water intrusion in the drive oil. So I believe you will be fine.

otgdy · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

The upper seal you mention is that under the top cover or is that down here also ?
I was told that there 2 seals in the hole you pictured. If I push the seal in far enough it
just falls in. Is this because there is supposed to be another seal under it ?

Fishermark · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

There is only one seal in the place where I have pictured - and the seal I have pictured there is the right seal. If your seal just falls in, then I suspect you have the wrong seal.

dubs283 · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

otgdy said:
The upper seal you mention is that under the top cover or is that down here also ?
I was told that there 2 seals in the hole you pictured. If I push the seal in far enough it
just falls in. Is this because there is supposed to be another seal under it ?

yes, there are two seals in that area, one seals the bottom part of the upper housing driveshaft, the other seals the lower unit driveshaft where it enters the upper housing

the upper seal keeps lube in, the lower seal keeps water out (mainly to ensure the splines don't weld together, but also to keep the oil clean)

you either have the wrong seal or becuase there is little in the way of a seal surface in the housing is the reason for your seal not staying put

you install the upper seal through the top cap of the driveshaft housing and the lower seal (where your housing is broken) through the exhaust passage

it is up to you how you want to proceed, jb weld, rtv, etc... my recommendation is to get a new housing and swap the guts but that requires shimming, special tools, and a working knowledge of how to do it

otgdy · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

Should I be able to see the top seal if I look into the broken hole ? The passage looking into the broken hole starts at the diameter of the seal then it gets suddenly bigger as you go into it. There is a 90 degree ledge in there .. definitely a machining. The bigger diameter section of the hole is where the upper seal should reside ? I am wondering if I have to dismantle the top section or not.

Don S · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

I am wondering if I have to dismantle the top section or not.

Yes

otgdy · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

That's what I didn't want to hear.
Thank you for the help.
Really appreciate it !!

OTG

Fishermark · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

Just so you understand what everyone is saying - yes you do have to dismantle the upper in order to replace the upper seal - the one that seals the gear oil.

No - you do not have to dismantle the upper to replace the seal that you have pictured.

Don S · Mar 11, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

No - you do not have to dismantle the upper to replace the seal that you have pictured.

True, you don't have to, but if you want to do the job right, and check the other seal, and make sure you don't have problems on the 4th of July weekend, then you DO need to do it right the first time, and not keep little bits at a time until it finally works.

I think I mention something about that in my signature.

otgdy · Mar 12, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

Fishermark said:
Just so you understand what everyone is saying - yes you do have to dismantle the upper in order to replace the upper seal - the one that seals the gear oil.

No - you do not have to dismantle the upper to replace the seal that you have pictured.

I understand. I am surprised that someone rebuilt this unit and left the upper seal out completely.
Was hoping that I couldn't see it from this angle. Unless you can see it in the attachments that are not real clear.
I fully agree with you about doing little bits at a time. I have resealed everything except what is in the top cover.
(upper drive shaft housing ?)

I already added new u-joints,pump, bellows (all), coolant hose. Now when I dismantle the top for the upper seal. Will I need any special tools and/or adjust lashes if .. I just remove, replace seal, reassemble ? If everything goes back as it came out ?

OTG

dubs283 · Mar 12, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

otgdy said:
I understand. I am surprised that someone rebuilt this unit and left the upper seal out completely.
Was hoping that I couldn't see it from this angle. Unless you can see it in the attachments that are not real clear.
I fully agree with you about doing little bits at a time. I have resealed everything except what is in the top cover.
(upper drive shaft housing ?)

I already added new u-joints,pump, bellows (all), coolant hose. Now when I dismantle the top for the upper seal. Will I need any special tools and/or adjust lashes if .. I just remove, replace seal, reassemble ? If everything goes back as it came out ?

OTG

if somebody had left the upper seal out you would know, you wouldn't have a drive - there would be zero oil in the upper and the gears would be spent

as far as special tools, there is a retainer wrench needed for removal and more importantly installing the retainer to the proper torque and a seal installation tool for the seal(s)

you wont have to worry about shimming anything if you just remove the guts and reinstall them, if you get a new housing you will have re-shim everything though

Fishermark · Mar 12, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

Don S said:
True, you don't have to, but if you want to do the job right, and check the other seal, and make sure you don't have problems on the 4th of July weekend, then you DO need to do it right the first time, and not keep little bits at a time until it finally works.

I think I mention something about that in my signature.

I'm all in favor of doing things right "the first time." I don't know the condition of the drive or the OP reason for doing this work. I just want to make sure he understood that the seal in question is not difficult to R&R and does not entail disassemblng the drive.

Anytime work is done on the drive it should be pressure tested, and if there is an issue then fix it. (I did not emphasize that point, and perhaps should have). I do, however,think it is premature to suggest to him that his drive needs to be disassembled and seal(s) replaced that may not need to be done, that's all.

Regarding the broken area - again, we cannot see his drive and cannot tell how bad the break / crack is. The original poster seems to think there is no upper seal in place at all. As Dubs mentions, that should be obvious whether or not a seal is in place there. If there was no seal there, it would certainly be discovered with a pressure test. I doubt it will hold much pressure without that seal.

(The UPPER seal, not the lower seal).

otgdy · Mar 12, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

dubs283 said:
if somebody had left the upper seal out you would know, you wouldn't have a drive - there would be zero oil in the upper and the gears would be spent

as far as special tools, there is a retainer wrench needed for removal and more importantly installing the retainer to the proper torque and a seal installation tool for the seal(s)

you wont have to worry about shimming anything if you just remove the guts and reinstall them, if you get a new housing you will have re-shim everything though

I purchased this boat from a guy who had the outdrive "totally rebuilt". Doubt it was ever put in the water afterwards.
While replacing the impeller (most of it was up in the power steering cooler) I noticed the shift cable bellows had water in and also saw that there was no clip on it or cement on the other end. Pulled the lower unit and replaced all the seals orings in it. While the lower unit was off I removed the clamp on the drive shaft bellows and pulled it off with my hands. No glue. Pulled the upper unit and purchased all new bellows. Noticed the drive shaft bellows was full of water and the ujoints were rusted real bad. The u-joints were solid but I replaced them anyway. In getting to the u-joints had to remove the circular nut so I could move the shaft outward and get the tool on the ujoint to press it out. Replaced all the seals orings on the drive shaft. Now here I am with these seals. Good news is I don't have to re-shim etc. Just have to find the retainer wrench and seal install tool. The seal install tool is because one of the seals (upper ?) is installed "backwards" ? ( U = edges pointed up).

Wish someone told me I could purchase a completely rebuilt outdrive for about $1600 and get a guarantee with it.

The retainer wrench you mentioned.. is that the one with a hole about the size of an oil filter ?

OTG

dubs283 · Mar 12, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

otgdy said:
The retainer wrench you mentioned.. is that the one with a hole about the size of an oil filter ?

yep, it should have a 1/2" square hole on the narrow end for your 1/2" drive torque wrench

overall torque on the retainer is 200 lb/ft, it is determined by the length of you tourque wrench - there is a chart in the OEM manual to determine the setting

otgdy · Mar 19, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

Fishermark;3666371 Anytime work is done on the drive it should be pressure tested said:
Well I opened the top of the outdrive and there was a brand new seal in there. Now I look at the bottom of the unit and don't know how I could have missed it. I replaced this and the smaller seal (in the broken housing). Cleaned it up real good and sealed it with the "RIGHT STUFF". Hopefully this will hold. Been impressed with it so far.
I am definitely going to get it all pressure checked prior to putting it on the boat. Don't want to mess with the bellows and coolant hose more than I have to. Can I do this pressure check without getting real deep in custom tools etc ?

Thanks
OTG

Fishermark · Mar 20, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

In the DIY section at the top of the page, there is a post on homemade special tools. You can find how to do it and how to make your own pressure tester. Very easy and inexpensive.

achris · Mar 20, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

otgdy said:
The retainer wrench you mentioned.. is that the one with a hole about the size of an oil filter ?

Here -> http://www.iboats.com/Boat-Motor-Pa...egory.f--session_id.019488540--view_id.268604

Chris........

otgdy · Mar 21, 2012

Re: Alpha 1 Upper unit Drive Shaft seals

Fishermark said:
In the DIY section at the top of the page, there is a post on homemade special tools. You can find how to do it and how to make your own pressure tester. Very easy and inexpensive.

Thank you for the link. Will hopefully check it this weekend.

OTG

Alpha 1 Upper unit Drive Shaft seals

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