Leaking outdrive--Merc alpha 1--now what?

[nola mike]

so i got a replacement alpha 1 outdrive after my upper gearset disintegrated after getting water in the drive. "new" drive had some milky oil in there interspersed with good-looking oil. i just removed the lower drive to replace the water pump (glad i did--impeller looked rough). a couple of questions:
1. there was water between the lower pump housing and the blue seal (see pic). doesn't seem like that should be the case, right? what is that seal, and how do i remove/replace it?
2. there looks like there should be a small o-ring on the drive shaft, which i don't see. is it possible that this wasn't replaced at some point, or is it hiding in the upper case somewhere?
3. the kit came with 4 large o-rings. i see a use for one of them beneath the lower pump housing--are the others extra, or do they replace something i'm not seeing?
4. kind of stupid, but i don't see where the gear oil communicates between the upper and lower housings.
5. other seals that should be replaced before i put this back together?

 

[Don S]

Re: Leaking outdrive--Merc alpha 1--now what?

You might want to do a lot of checking before you put a new upper on the lower. Every drive I have ever taken apart that lost the gears on the upper, had sever damage and a lot of metal in the lower section also. This takes out the lower and will also destroy your new upper as well.

That blue seal you are referring to is part of the pump base that is stuck in the lower unit, you need a new pump base and seals.

I would strongly suggest you head up to the Adults Only sticky and download the OEM service manual for your drive. I would tell you which manual, but you give no indication of year, so it's impossible to say for sure.

As far as which seal goes where, who knows, impossible to say what a big seal is compared to a small seal. The manual should help, and if it's an OEM kit, then it may be for several different drives, or pumps, again we don't know what kit you have.

Here is your picture that explains the oil passage.

 

[Bt Doctur]

Re: Leaking outdrive--Merc alpha 1--now what?

That blue part was part of the pump base and is not supposed to be removable.The O ring was used if the shaft had the groove for one, the oil passage between the drive is the hole at 12:00 in the pic and a seal goes there .

 

[nola mike]

Re: Leaking outdrive--Merc alpha 1--now what?

thanks for the help guys.
@Don: i'm not using the old lower; i bought a complete used unit with an unknown maintainance history, and am freshening it up before reinstalling. i have the service manual, and didn't see the o-rings on the diagram. i have a complete sierra pump kit including new base. thanks for the help with the pic; the old pump base is next to the shaft on the left side, and that's the side that was facing the blue piece.
@BT: yeah, the shaft has a groove for an o-ring, but there isn't one there. i wasn't sure if someone didn't put one in last time (maybe causing a leak) or if the o-ring is stuck in the upper unit somewhere.
@BT/Don: so is the blue piece NOT supposed to be removable, or was it supposed to come out with the old base?

 

[Don S]

Re: Leaking outdrive--Merc alpha 1--now what?

@BT/Don: so is the blue piece NOT supposed to be removable, or was it supposed to come out with the old base?

I wondered if you would read it wrong when he posted this:

That blue part was part of the pump base and is not supposed to be removable.

What he meant, was that it's part of the pump base and shouldn't have been removable (aka BROKEN) from the pump base. It does come out of the drive. One way or the other.

 

[Bt Doctur]

Re: Leaking outdrive--Merc alpha 1--now what?

Thanks for clearing that up ,Don. Read it before it was posted and didnt catch it.

 

[nola mike]

Re: Leaking outdrive--Merc alpha 1--now what?

gotcha--just didn't want to break something by prying on it wrong...
so, aside from all the gaskets that came with the water pump kit (including the oil passage gasket), are there any other common potential leaking seals that i should check on/replace before reassembly?

 

[ziggy]

Re: Leaking outdrive--Merc alpha 1--now what?

are there any other common potential leaking seals that i should check on/replace before reassembly?

check the drive shaft in the lower for seal wear. it'll occur at the the water pump base seal and the seal that's in the upper that contacts the lower drive shaft just below the splines.
you don't need to install the oring on the drive shaft just below the spines. that groove on the drive shaft was eliminated on later versions. i've been running w/o for 2 years now, no consequences...
as for leaking seals. you can find out prior to install of the drive. just pressure test it on the bench. if she holds, yer good to go, if she leaks down, ya need to go find out where... i always pressure/vac test after i R&R my impeller, just to be sure i think i got it right..

 

[CheapboatKev]

Re: Leaking outdrive--Merc alpha 1--now what?

check the drive shaft in the lower for seal wear. it'll occur at the the water pump base seal and the seal that's in the upper that contacts the lower drive shaft just below the splines.
you don't need to install the oring on the drive shaft just below the spines. that groove on the drive shaft was eliminated on later versions. i've been running w/o for 2 years now, no consequences...
as for leaking seals. you can find out prior to install of the drive. just pressure test it on the bench. if she holds, yer good to go, if she leaks down, ya need to go find out where... i always pressure/vac test after i R&R my impeller, just to be sure i think i got it right..

Heres Ziggy's super duper OD pressure tester rig..Was looking for myself so thought I'd make life easy for you and show you.

http://forums.iboats.com/showthread.php?p=1573303#post1573303

 

[TilliamWe]

Re: Leaking outdrive--Merc alpha 1--now what?

nola mike, I thought you were going to pressure test this used drive before you bought it? What happened?

Is all this really going to be worth the $1195 it would have cost to buy a brand NEW SEI SE106 Alpha One replacement drive, with a 3 year no fault warranty?

I wish you luck.

 

[nola mike]

Re: Leaking outdrive--Merc alpha 1--now what?

@kev: thanks, i'd seen that link--just got a gauge from harbor freight yesterday, tester build in progress...
@ziggy: see above. i just want to replace everything while it's apart before i get to pressure testing.

nola mike, I thought you were going to pressure test this used drive before you bought it? What happened?

yeah, you got me. ran out of time before having a chance to build one. since i saw a little milk in the drive, i knew there was a leak when i bought it. the upper gearset looked pristine though (as did the oil up there), and it seemed like the water was confined to lower unit, which i guess is odd.

Is all this really going to be worth the $1195 it would have cost to buy a brand NEW SEI SE106 Alpha One replacement drive, with a 3 year no fault warranty?

I wish you luck.

yup, totally worth it--assuming it lasts
actually, even if it doesn't, this drive was cheap enough that it was worth the price i paid for the SS prop that came on it. and the water pump/seals are only running me $40 or so. plus i guess $7 for new oil. and besides, this stuff is fun for me--would have been less so during the summer when i would have wanted to get on the water ASAP, but now i have all winter to work on it with no time constraints, and i get to learn about the outdrive and how it works. i think many on the forums have the same interest, no?

 

[CheapboatKev]

Re: Leaking outdrive--Merc alpha 1--now what?

yup, totally worth it--assuming it lasts
actually, even if it doesn't, this drive was cheap enough that it was worth the price i paid for the SS prop that came on it. and the water pump/seals are only running me $40 or so. plus i guess $7 for new oil. and besides, this stuff is fun for me--would have been less so during the summer when i would have wanted to get on the water ASAP, but now i have all winter to work on it with no time constraints, and i get to learn about the outdrive and how it works. i think many on the forums have the same interest, no?

I am with you Mike..
I picked up a complete OD as I was having an issue with my lower on my current drive..For 75 bucks, it was well worth it...I too have become fairly intimate with the inner workings (to a point) of how the OD system works and have gained a LOT of confidence and knowledge along the way..Things you cant put a price tag on..
I also couldnt afford a new SEI drive at this time...As much as I love my boat, other things have to come first when there is limited funds.

 

[nola mike]

Re: Leaking outdrive--Merc alpha 1--now what?

I am with you Mike..
I picked up a complete OD as I was having an issue with my lower on my current drive..For 75 bucks, it was well worth it...

$75? now i feel like i got robbed for $175! yup, only when you take something apart does the mystery of it disappear...and besides, $1200 for a brand new drive on a 24 year old boat doesn't sit right with me.

 

[CheapboatKev]

Re: Leaking outdrive--Merc alpha 1--now what?

$75? now i feel like i got robbed for $175! yup, only when you take something apart does the mystery of it disappear...and besides, $1200 for a brand new drive on a 24 year old boat doesn't sit right with me.

Its Florida..heck theres a gazillion rotten glass boats out here with donor parts, maybe different in your neck of LA..

But if I did have the $$$, I'd spring for the SEI unit..I do plan on it when I have the funds..I have no qualms putting that $$ into (onto) a 41 year old tub (which I have). The "new OD smell" would be worth it, along with the peace of mind of the 3 year warranty, but cant spring for it now.

 

[cr2k]

Re: Leaking outdrive--Merc alpha 1--now what?

The O-Ring issue on the vertical drive shaft....If there is a groove just below the splines there should be an O-Ring there. Either it got left off last time apart or it came off when pulling the lower. If the later is the case look up in there and see if you can see it. If it is in there you will most likely not get the lower back on with out removing it as it will get pushed up in the splines. This O-Ring is to keep the spline grease in place.

As to the mess of larger O-Rings in the pump kit they go with the extra gaskets and are for different application. Kind of a "universal" approach to the kit, however in 16 years I have never seen a unit that used anything different.

Don't forget to check the prop seal. Look for fishing line etc. This is a common cause of leaks in the lower.

Good luck with your project.