Alpha 1 Gen 2 Drive shaft housing oil seal compatibility.

[Simoniz]

Ive got to replace the lower (Driven shaft) oil seal on my Alpha 1 Gen 2 Outdrive, Engine no OL 634881.

Having disassembled the drive shaft housing, and removed the old seals, Ive discovered that my drive has 2 separate seals installed back to back.

The seal kit which I have, part No 26-88397A 1 has a double seal, ie 2 seals in one. Is this compatible, given that the gearbox housing drive shaft will have run on the 2 seals which would have had their lips in different places?

Thanks for any advice.

 

[alldodge]

Need to know what your drive serial number is to determine which seal would be needed

Notes for Part Number 864319

SN# 0M400412 & UpCOMPONENT OF DRIVESHAFT HOUSING SEAL KIT [26- 88397A 1]

Notes for Part Number 66302

SN# 0M400410 & BelowCOMPONENT OF GEAR HOUSING SEAL KIT [26-816575A 3] COMPONENT OF WATER PUMP REPAIR KIT [817275A 4]

Item 5
https://www.mercruiserparts.com/bam/subassembly/30862/2686/110

 

[Simoniz]

Need to know what your drive serial number is to determine which seal would be needed

Notes for Part Number 864319

SN# 0M400412 & UpCOMPONENT OF DRIVESHAFT HOUSING SEAL KIT [26- 88397A 1]

Notes for Part Number 66302

SN# 0M400410 & BelowCOMPONENT OF GEAR HOUSING SEAL KIT [26-816575A 3] COMPONENT OF WATER PUMP REPAIR KIT [817275A 4]

Item 5
https://www.mercruiserparts.com/bam/subassembly/30862/2686/110

Hmm, I dont know, Im afraid.

I know the engine No (see OP) and the transom No, and the 12 digit boat no, which shows that the boat was built in the year 2000.

I know that the original fitment was the 2 separate seals back to back. My question is whether I can use the newer style 1 piece double seal.

 

[alldodge]

Unable to say for sure but maybe @Bt Doctur or other can advise.

Similar happened with older Bravo drive, it went from 2 seals to one double. Was not for my older model but I installed and worked just fine

 

[Simoniz]

So Ive now ended up with a choice of the old style 2 separate seals and the newer 2 seals in one standard; Ill have a look later and see which I like the look of best, but Ill probably use the 2 separate seals.

When disassembling the top cover of the drive shaft housing, all the bolts were extremely tight and difficult to remove, and one broke off, and the remaining broken portion had to be machined out and a helicoil inserted. I read somewhere that it's a good idea to apply a thin coat of Perfect Seal to the threads to help prevent this happening again. Is this a good idea, or is it going to trap and compress the air in the blind hole under the bolt (obviously, Im going to make sure that theres no oil in the holes)?

 

[Fun Times]

There's an area on the top cap (or drive housing) that's recommended to apply perfect seal before installing but the bolts are not one of them, so it becomes preference and sometimes what type of water you boat in and/or how long the boat sits in the water but the torque for the screws are 20 lb-ft (27 Nm).

Page 90-818177--3 APRIL 2001 Page 3A-45
DRIVE SHAFT HOUSING
SERVICE MANUAL NUMBER 14
Final Reassembly
1. Assemble the O-ring to the top cover.
2. Apply Quicksilver Perfect Seal to the top cover (or the drive shaft housing) in the area highlighted in the next figurer.
3. Install the top cover and torque the screws to 20 lb-ft (27 Nm).

https://manualzz.com/doc/9196301/mercruiser-alpha-one-tehnicheskoe-obsluzhivanie-i-remont-4

 

[dubs283]

I've used gasket sealer on the top cap bolt threads without fail for years along with the recommended o ring seating area between the cap and housing. Others use grease and that's fine, the main point being it is ime better than installing the bolts dry

As far as the seals in question you can go either route. Use the one piece which is updated from the two individual seals or use the individuals back to back. The only caveat being you must insure the two individual seals are installed properly. Upper has lips facing up, lower has lips facing down. The one piece, double seal has a slight taper on one side for easier install and is basically fool proof.

The mercury special tool for seal insertion isn't specifically required but makes install much easier