82 Merc Type 1 sterndrive slowly leaking gear oil

[Mike V]

I purchased an 82 4winns with a Merc 120 Sterndrive, it runs fine but I noticed a small puddle of gear oil that came out of a "drainage" hole opposite the oil drain screw; I purchased the Seloc Manual but it doesn't even show this hole. I just need a push in the right direction(it has drained about 3 tablespoons so far; I am hoping it is a gasket somewhere.
Definately has the gear oil smell.
thanks for any info ahead of time!

Mike

 

[Haut Medoc]

Re: 82 Merc Type 1 sterndrive slowly leaking gear oil

Welcome to iboats.....
Yes, it sounds like a seal....
Drain the drive & pressure test it using 15#'s of air.....
It should hold that all day long......
But, since it is obviously leaking, take some soapy water & brush it on to see where the leak is.....
My guess is the shift shaft seal.....
Unfortunately the tools and techniques are generally beyond the realm of the DIY guy......
My advice is to take it to a shop & have it resealed or if the wallet permits, get a new SEI aftermarket off ebay with a three year guarantee for about $1200 shipped......
Here is a manual for a a drive almost identical to yours, so you can see what is involved......
http://www.boatfix.com/merc/Servmanl/6/6A2R3.PDF​

 

[Mike V]

Re: 82 Merc Type 1 sterndrive slowly leaking gear oil

Thanks for the welcome and information Haut!
If I buy the new unit is it DIY easy enough to swap? I have a garage and tools (not boating tools as of yet) but almost everything else.

And what is that "drainage" hole on the bottom of the lower unit called (opposite side from the drain plug)

Going to see what the Wife says.
Thanks again!
Mike

 

[Haut Medoc]

Re: 82 Merc Type 1 sterndrive slowly leaking gear oil

Yes, putting on a new unit is very doable for a DIY....
You should check the alignment with the alignment tool while the drive is out....
If you are referring to the drainage hole at the front left of the drive where I asuume that you are leaking your gear oil from, it is called the "Drainage Hole" as far as I know.....
It's primary purpose is to let water drain from the exhaust cavity to prevent freeze damage to the drive when stored in the 'trailer' position....
Which is something I never do....
It's secondary purpose is to let you know if you have a bad shift shaft seal.....​

 

[Mike V]

Re: 82 Merc Type 1 sterndrive slowly leaking gear oil

Excellent & wife says I can get a new lower unit this winter; So I'm going to chance it and use it to fish this weekend (4 hours with 2 other boats) if I have issues I can use my trolling motor & new deep cell.
Will sleep alot better once I have the new unit! Parking her after this excursion.
Thanks Again Haut!
Mike