Lower Unit leaking oil, '92 120hp

[Rope Goat]

Well, I'm glad to see this website is updated, the last time I looked the posts were all from 2002 and older....anyways, I'm glad to join in and hope I can help some folks out in return for a little advice for myself.
I'm a weekend warrior wrench twister, and have fairly decent mechanical skills, along with my trusty Chilton manual.
Anyways, here's my question: My 120 over the last few weeks (since I've been out boating alot more, recently) has lower unit oil leaking out of the weep holes (the factory ones in front of the prop).
I dropped the lower unit this evening and it looks normal inside all the cavities, but then when I drained the oil out, it was about 1/3 water.
I believe I need to replace some or all of the seals in the lower unit (not the little gaskets on the fill/vent/drain plugs, of course I always replace those!). Can I just keep on checking and replacing the oil until I can get the lower unit off again and taken in for a seal replacement? I bought a complete seal kit off of Ebay, it's too complicated for me with the shimming of the gears and all. I can definitely tackle a water pump impeller replacement, if that's where the typical water intrusion leaks occur. I've perused all of the old posts and alot of the new ones here....so please weigh in and help a new poster out!!! thanks!

 

[captquest]

Re: Lower Unit leaking oil, '92 120hp

IMO you should use that rebuild kit and replace all your lower unit seals. If there is water getting in that is not good, and I would not run it like that. You may not have adequate lubrication and do some damage. You may just have some leakage in the main assembly seals or in the drive shaft or shifter seals. Here's a little trick that a mechanic friend of mine showed me. First you need to drain and remove the lower unit from the motor. If you have an air tank or even a bicycle pump, try pumping air into the lower unit through one of the filler holes. I use a plastic nozzle that came with the bicycle pump. I screw it into the threads (careful not to break it). When you force air into the unit you should hear it leaking out, try to pinpoint where it's coming from, that will be the sourse of the leak. Hope this helps good luck.

 

[Rope Goat]

Re: Lower Unit leaking oil, '92 120hp

Thanks for the idea, I'll see if I can jury-rig the bike pump I've got and give it a try. I pulled the lower yesterday, and there was definitely a good amount of water mixed in the lower oil...I hope I found it in time before messing up those gears!! I'm also going to take it to my local repair shop and see if they can squeeze it into their schedule!