Alpha 1 Gen 2 Lower Unit Oil Leak

[w102acd]

I have a 2005 Glastron MX175 with a Mercruiser 3.0L Alpha 1 Gen 2 and 200 hours. This is my first boat and just finished the first season.

Throughout the season, I noticed the lower unit oil reservoir would need topped off. We probably put 50 (or so) hours on it this season and went through maybe 1.5 quarts of lower unit oil just keeping it topped off. We trailer the boat and keep it in the garage and it does not leak when sitting in the garage (ie no oil on the floor).

Obviously a bad seal, but how would people with more experience proceed?

Option 1: Do nothing...just keep topping it off when it needs. I assume this has some risk since if oil gets out...water can get in?

Option 2: Rebuild the lower unit. I am pretty mechanically inclined and think I could handle it, but don't want to get in over my head. I saw seal replacement kits and they seem relatively cheap, but as with anything labor is the killer. If I go this route, should I be replacing other stuff while I'm in there. The boat is 11 years old, but only has 200 hours on it. Other than this and a plugged speedometer (hit a stick), the boat had no issues.

Are there checks I can do to see where the leak is or better diagnose the issue? I have heard of a pressure check, but have not been able to find the specifics of how to do this (assuming I can).

Lastly, with it being the end of the season (in Ohio), it is a good time to do the repair if that is the right thing. I am winterizing the boat today, but am not changing outdrive oil until I figure out what to do with it.

Thanks in advance!

 

[shaw520]

WIth that amount of oil loss you should be seeing something,..while sitting still after motoring, look closely around your outdrive for floating oil,.. one drop make a pretty large area thats visible at the surface. Also look on the inside of the transom where the drive shaft goes through,.. oil maybe accumulating in drive bellow. Also check lines and bilge area to determine where oil is leaking from.

 

[w102acd]

I have not ever noticed oil in the water (but have not really been looking) or down in the bilge area. I will have to check the other areas, but doubt that much oil is still in the boat.

 

[Bt Doctur]

the gen ii`s tend to leak at the driveshaft seal under the water pump impeller

 

[w102acd]

Thanks...so replace or leave as is? Is there any way to test it?

 

[enginesilo]

I had the exact same issue on my 2005 Sea Ray a year back. After topping off my reservoir all season at the end I pulled the boat and when on the trailer mine was leaking a tiny bit around the weep hole where water pours out of the Outdrive. I pulled the drive, split the upper and lower, did a simple pressure test and sprayed it with soapy water to find the location of the leak. Mine was the shift shaft bushing. While in there you can easily do your water pump and other easily reachable seals. The job wasn't hard at all and by pulling and pressure testing you are sure to find the leak.

Now that it's fixed my reservoir didn't lose 1 drop all season long. I would suggest fixing it, its bad and sad to be losing that much oil into the water when you can fix it. Let us know if you have any specific questions.

 

[bspeth]

Remove it from the boat and pressure test it,replace any seals that are bad.

 

[w102acd]

Alright...can someone describe how I go about pressure testing the outdrive. Should I take the entire outdrive off or just the lower unit to start?

 

[enginesilo]

Alright...can someone describe how I go about pressure testing the outdrive. Should I take the entire outdrive off or just the lower unit to start?

I would suggest pulling the entire drive off. Then build a simple pressure tester, if you look around the forums or search Google you will see all sorts. Mine was made of some simple tubing and a pressure gauge, and a bike tube valve to put air in.

My guess is your leak may be on the lower so you could start with that only, but I was pulling my drive to inspect alignment and bellows anyhow so it was easier to take it off whole.

I tested the upper and lower while together, and I then split the upper and lower and pressure tested them separately. Didn't take long to find the leak.

Here is a thread on the topic. If you google "alpha 1 gen 2 pressure test"you'll find lots on the topic:
http://forums.iboats.com/forum/engin...n-2-vacuum-too

 

[w102acd]

Very much appreciated! I will be gone all week so will probably have some questions when I return. Should I order an entire seal kit or just find the problem(s) and fix those? I have time to have a look and then order what I need, just don't know if I should just do it all while in there. Reminder, the boat is 11 years old with 200 hours.

 

[enginesilo]

Very much appreciated! I will be gone all week so will probably have some questions when I return. Should I order an entire seal kit or just find the problem(s) and fix those? I have time to have a look and then order what I need, just don't know if I should just do it all while in there. Reminder, the boat is 11 years old with 200 hours.

I would pressure test and see what seals may be leaking. I don't know these outdrives that well since I've only split mine 1 time, but I changed the shift shaft bushing (This is where my leak was), the water impeller (Full kit including new housing, impeller, gaskets, etc), and the Carrier Assembly seal. I'm not sure if there are any other seals inside that can be easily changed without taking the actual outdrive apart and then you need serious tools and knowledge. If your leak ends up being from an inner seal then you will have no choice, but if it is one of the ones I mentioned that are easy to reach you will be good to go.