Oil leak help, Alpha 1 Gen 2 lower

[Jt93fd]

Hello,

It seems I have a large oil leak with oil actively dripping out of the hole about an inch and a half down on the starboard side, just below where the upper and lower drives are bolted together.

I am planning on doing a new impeller service myself on this, and is this leak indicative of the small o-ring next to the impeller housing leaking?

2002 bayliner 1750 3.0

 

[Bondo]

Ayuh,..... Welcome Aboard,..... That's a weep-hole that allows water to drain, 'n not freeze bust the castin',....

The little quad-ring rarely just fails,....

It's more likely a seal, donno which one,....

When ya drop the lower unit, follow the oil trail Up to it's origins,....

 

[enginesilo]

I had the exact same issue last season and I would imagine there is a chance it might be the same problem. Could very well be that little o-ring between the upper and lower, but if it sporadically started leaking out of nowhere chances are it is ok. I too thought that was the problem on mine but once I did a pressure test I found the true problem. I would have a little bit of oil (Less than yours, but same location) leak out whenever the boat was out of the water, and while in the water I would lose a little from the reservoir. I pulled the outdrive this past winter and split the upper from the lower. Mine ended up being the shift shaft bushing. This is the little piece that houses the shift shaft, and the small gaskets tend to leak. The process was simple once the drive was off the boat and the upper and lower were split. Redoing your water pump impeller if you haven't done it in a long while while you are already in there is a great idea.

Once you split the upper from the lower you won't truly know if that little o-ring that splits the upper from the lower is the culprit unless you reassemble everything. I did a simple pressure test and that's how I found out it was the shift shaft bushing. Yours could very well be either of these problems.

Here is the part and a picture so you can get an idea of what it is:
http://www.amazon.com/MERCRUISER-ALP.../dp/B004AR159O

Good Luck

 

[Jt93fd]

Thank you, I'm going to pull off the lower today and check it out, I'll be back with my findings

 

[Jt93fd]

No Title

Ok, I just split the upper and lower unit and there's quite a lot of buildup inside. The o-ring for fear lube between upper and lower was ok.

The shaft seal above water pump was ok it seems. Shaft came out with small amount of oil on top, the bottom was darkened from exhaust and old residue.

The shift shaft plastic assembly is covered in oil, and when I separated the upper from the lower the thicker gasket around shift shaft at top of housing was not mounted all the way down.

Oil is now draining out of the weep hole right above the shift elbow (?) on the upper unit. See photo.

The lower shift shaft plastic housing and water impeller service should definitely be replaced, yet I am not sure about upper drip.

See photos and any advice is greatly appreciated

 

[Jt93fd]

I just cleaned up all the dripping gear oil and disassembled the water impeller housing, the plastic shift shaft assembly, and it's all much better looking and less oily now.

After the gear oil stopped dripping out of the weep hole above the upper unit's shift elbow, I noticed that hole is a vent for just beneath the gaskets around the oily top of the drive shaft and the exhaust area of the lower unit where engine exhaust normally resides. What happened was the residual oil coming out of the drive lube monitor reservoir was still dripping onto the upper unit's area where the drive shaft aligns to the cogs. due to no drive shaft being there, the oil dripped into the shift shaft area in the upper housing, coming out of the weep hole.

I removed the clamp I had on the gear lube monitor's hose, and I saw it dripping down the gear shaft cogged area of the upper unit and then coming out that weep hole again. I clamped hose again and dripping stopped.

From flashlight inspection and finger feeler test the o-rings that seal the oil around the drive shaft's upper area are OK.

Correct me if I am wrong, but it looks like there is no additional issue other than shift shaft plastic assembly and also regular water impeller gaskets and what not.

 

[Bondo]

Ayuh,..... Did you pull the entire drive, or just the lower unit from the upper unit,..??

Yer diagnosis of the leak don't add up,.... I agree it's leakin' with the lower unit off, but it was leakin' Before ya pulled the lower unit,....

Ya might have to pressure test the units to find the bad seal,....

 

[Jt93fd]

Bondo, I pulled the lower unit from the upper.

I'm relatively new to boating mechanics, so I wouldn't doubt if I am off on the diagnosis. I installed water impeller repair kit and also new shift shaft bushing assembly.

I guess I have done all I can do with lower unit off? It would be great if there was a way to test without needing to reattach upper and lower units, but I haven't thought of a way.

 

[Bondo]

I guess I have done all I can do with lower unit off? It would be great if there was a way to test without needing to reattach upper and lower units, but I haven't thought of a way.

Ayuh,..... Pull the upper off,... On the bench, plug the oil hole, 'n pressurize to 'bout 10/ 15 psi, 'n check the seals with soapy water,....

Lotsa Great learnin' in Don'S Adults Only section,.... Go spend some time, 'n poke 'round,....

 

[Jt93fd]

There's a ton of good material in there.

I finished cleaning up lower unit, and pressurized it to 10 psi through drain on bottom of unit and plugging top oil hole (where o-ring sits). It held steady at 10psi. For the heck of it I loosened the new shift shaft bearing assembly and it did leak as expected. Lower unit looks great now.

I'm removing the upper unit now

 

[enginesilo]

There's a ton of good material in there.

I finished cleaning up lower unit, and pressurized it to 10 psi through drain on bottom of unit and plugging top oil hole (where o-ring sits). It held steady at 10psi. For the heck of it I loosened the new shift shaft bearing assembly and it did leak as expected. Lower unit looks great now.

I'm removing the upper unit now

You are figuring out a ton of this on your own, good work. Yes that oil you found on the shift assembly was dripping from the upper, I too had a big gush pour out and was worried a seal in my upper was toast, but I realized it wasn't the case once I started to clean things up.

The pressure test is the sure way to figure out what is leaking. One thing to note, you already changed out the shift shaft bushing, so that may be why it was leaking and your problem may be solved. The upper may be fine as is, but it doesn't hurt to pressure test it to be sure. I did a pressure test separately on my upper, lower, and then together once they were reassembled. I would say do a pressure test on the upper, if it holds pressure, reassemble and do the test again. Use a bottle with water and some soap mixed in and spray areas of the drive, if a leak is present it will bubble and you can pinpoint it exactly. If you still have the lower separated it might be worthwhile to retest it and spray with soapy water if you didn't in case there is some other leak as well. From what I understand there are more serviceable areas on the lower versus the upper where it requires more tools and skill.

If you ever come across another issue its usually best to do the pressure test first since that will lead you directly to the problem areas. In my case the shift shaft bushing was the culprit and I had the exact same symptoms and experience as you. Hoping it is also your problem and it is solved. If the upper is having leak issues, from what I read it is mostly a seal that cannot be easily changed and requires special tools, basically not a DIY type job. It was my first time breaking open a drive though so others can chime in if you find new issues in the upper.

For reassembly of the outdrive once you have it back together, a member here on the board (@achris) has an awesome video on how to reinstall, check it out:
https://www.youtube.com/watch?v=aGVrY4cWiDA

Give us an update once you get further!

 

[Jt93fd]

This boat has kicked my *** today. I'm physically beaten.

I was not able to remove the upper yet. I tried to remove the upper without reattaching the lower. I wasn't able to do it though because I could not latch gears all the way into forward gear without locking propeller into place. So I put the lower back on, lining up drive shaft splines and having gear in forward. Piece of cake, threw two bolts in just to hold them together.

Removing upper and lower combined (am I missing a step??!)
Remove trim Rams, remove six bolts on back side, ensure speedo tube is still disconnected, make sure it's in forward gear with prop clicked in, and rock it open and off. I've seen all the youtube videos about it and lots of reading but I cannot figure it out. I have no power steering, so there is nothing to disconnect on opposite side of transom, right? Out drive is about 1/8 inch off of gimbal mount and even with some tapping and prying I cannot get it off.

Yes, you are right I've learned lots in just a day of wrenching!

Unfortunately I cannot just pressure test as a whole and forget about removing outdrive because I damaged gimbal to upper unit gasket in my battle with it and now it must be replaced as well

 

[Eric 3.7LX Alpha 1]

corrosion is keeping it on there, or possibly bad alignment.... It most likely hasn't been off in years. could be the shaft going thru the gimbal bearing or the front of the splined shaft in the coupler which is bolted to the flywheel on the back of the engine.

 

[Jt93fd]

Eric- I wouldn't doubt it, I have no idea how long it had been since it was removed.

I was finally able to get the entire upper and lower units removed! I used the trim hydraulics and also a block of wood to remove it and I made an outdrive stand for my garage. Very primitive, but it will work.

I pressure tested upper unit and lower unit as a whole after cleaning it up and it holds 10psi for over half an hour. No drop whatsoever.

Bell housing looks fine as well. I went through shifter gears making sure linkage was tight while looking at it from the bell housing and it operates fine. I did notice a small crack in bell housing in center of lower exhaust cavity, just above shift elbow linkage. I cleaned it up and jb welded it, it isn't in an area that will cause issues after inspecting it and the surrounding areas.

I'm off to west marine to pick up a new drive to bell housing gasket kit, and I'll put this drive back on. My goal is to test it in the water this evening!

Any other good ideas to check?

Regrease everything while going back into boat, forward gear, etc?

 

[Jt93fd]

After taking boat out into water twice and a few days of sitting I can officially say the leak has stopped! It must have been the shift shaft bushing assembly!

Thanks again

 

[ckirk]

Thank you so much for posting this!!! I've had the exact same issue over the past few years with a 3.0L Mercrusier with an Alpha I Gen II drive; a mysterious very slow disappearance of lubricant from the gear lube monitor but no loss of gear oil in the outdrive and no water in lubricant. But after our first outing for the season this past weekend I noticed a small drip of gear lube on the skeg that was coming from the joint where the lower unit bolts up to the upper half of the drive. I just replaced the water pump impeller so I thought it might be the oil passage way seal, but now I will check the shift shaft this weekend when I have time to look into it, I may replace it anyway it is only $20.

Thanks Again.

 

[Jt93fd]

Thank you so much for posting this!!! I've had the exact same issue over the past few years with a 3.0L Mercrusier with an Alpha I Gen II drive; a mysterious very slow disappearance of lubricant from the gear lube monitor but no loss of gear oil in the outdrive and no water in lubricant. But after our first outing for the season this past weekend I noticed a small drip of gear lube on the skeg that was coming from the joint where the lower unit bolts up to the upper half of the drive. I just replaced the water pump impeller so I thought it might be the oil passage way seal, but now I will check the shift shaft this weekend when I have time to look into it, I may replace it anyway it is only $20.

Thanks Again.

It only takes a couple minutes once you've got the lower unit off!

Couple notes:
Make sure you remove e-clip on ring of lower shift shaft arm when it comes out. Mine was loose (it holds bushing assembly in place with a small indent on shift shaft) and fell into bottom of shift shaft hole. It took a few minutes to fish it out, thank God I saw it though! I'd recommend buying a new e-clip which is NOT part of assembly kit.

Don't forget to remove and reinstall speedometer tube

Have fun and don't forget your lube.