shift shaft seal leaking

[Jcris]

I've been using my boat a lot more lately and have noticed a drop in the oil level in the drive oil reservoir on top of the motor. I've added about a 1/4" of oil twice in the last month or so. I haven't been able to see any oil leaking until today. With the drive up (Alpha 1 Gen 2) I saw a small puddle of oil below the lower unit. Upon inspection it appears to be coming from the shift shaft seal. This is a small amount of oil but I don't want this to become a bigger issue. What is the best way to proceed? Can I safely put this off until next season? I average about 2-3 days a week on the water fishing for 4 hours at a time.

 

[alldodge]

IMO your rolling the dice: The drive heats up when running and the lube expands, some leaks out. When the drive cools back down things reduce so maybe some water comes in. Its just a maybe, but if enough water gets in, its new drive. Just my WAG

 

[Bt Doctur]

your risking a drive failure for $7.35 ? sierra 18-2009 26-89236

 

[Jcris]

I've never removed a drive but am experienced with automotive work. This seems a straight forward job but I'm unsure. Would you recommend I tackle this myself?
I've put only 20 hours on this boat since I bought it and don't know any of the maintenance history. This boat is a 1996 with about 1000 hours on it. My inexperience may not allow me to "see" other issues with the drive but I think it should be inspected. Thanks for your advise.
How long of a service life is typical for this drive?
What other things should be replaced as a part of maintenance while the shaft seal is being done?
Water pump? Impeller? other seals?

 

[Bt Doctur]

left a number

 

[alldodge]

I've never removed a drive but am experienced with automotive work. This seems a straight forward job but I'm unsure. Would you recommend I tackle this myself?

Sure, its not hard. Remove the drive, split in have by removing bolt, and then replace the seal
http://www.mercruiserparts.com/bam/subassembly/30860/1942/150

I've put only 20 hours on this boat since I bought it and don't know any of the maintenance history. This boat is a 1996 with about 1000 hours on it. My inexperience may not allow me to "see" other issues with the drive but I think it should be inspected. Thanks for your advise.
How long of a service life is typical for this drive?

Should last many more hours if regular maintenance is done. Change drive lube, and impeller every 5 to 7 years, or sooner if increased heat starts showing up

What other things should be replaced as a part of maintenance while the shaft seal is being done?
Water pump? Impeller? other seals?

Impeller is the only thing that needs to be done

 

[Jcris]

How critical is it that the engine alignment be checked with the special tool?

 

[alldodge]

If the motor is aligned, then its not needed, but if its not, then it will save you from replacing the coupler

 

[Jcris]

Is it necessary to remove the entire drive to replace the shift shaft assembly. From the service manual it looks like this can be done by just removing the drive shaft housing

 

[Bt Doctur]

you have to drop the lower unit and it MUST be in fwd gear http://www.boatfix.com/merc/Servmanl/14/14cover.pdf