Stern drive leak

Malibu496

Malibu496

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Jul 7, 2013
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Stern drive tank on engine shows empty after it sits for a few days and im finding oil mixed in with some water in the sump under the engine. 97 Bayliner 2050 with 5.7 and alpha 1 ... Line from tank to bulkhead fitting is clean...??
 
oldjeep

oldjeep

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Re: Stern drive leak

Is it sitting in the water or on a trailer?
 
Bt Doctur

Bt Doctur

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Re: Stern drive leak

input shaft seal and maybe the yoke is grooved
 
Bondo

Bondo

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Re: Stern drive leak

Malibu496 said:
Stern drive tank on engine shows empty after it sits for a few days and im finding oil mixed in with some water in the sump under the engine. 97 Bayliner 2050 with 5.7 and alpha 1 ... Line from tank to bulkhead fitting is clean...??
Click to expand...

Ayuh,... Welcome Aboard,... That line attaches to a plastic fittin' at the transom,... Look there,...
 
Malibu496

Malibu496

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Re: Stern drive leak

While sitting on the trailer for a few days or so.. And I've sourced the line back to the bulkhead where it goes in and it's all dry no oil on it... That's what's got me stumped... New to boats.. Been wrenching since I was 10 or so on cars and bikes...
 
M

MarkSee

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Re: Stern drive leak

As BT mentioned above a good chance the seal behind the yoke has failed and leaking gear oil into the bellows then making its way into the bilge.

This is what happened with my Bravo 3 unit and I had to replace the seal but other components to check as well.

Time to pull the drive, see if indeed you have a lot of gear oil in the bellows then do a pressure test using soapy water to verify that seal is leaking. Check out the sticky section for points on making a pressure tester and doing the test.

Mark
 
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Malibu496

Malibu496

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Re: Stern drive leak

I appreciate the help with the links and what not... My question now lies with the stern drive.. Once I pull the 4 nuts or whatever it is to pull the unit.. How envolved is it to change the seal to stop the leak back? With the unit out and off can I pull the input shaft and replace that seal or does it have to go to a shop ? For complete disassembly?
 
Bt Doctur

Bt Doctur

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Re: Stern drive leak

with the spanner wrench and some mechanical ability you shold be able to change it .You need to be careful. if it uses the inner spacer .then you just torque the nut. If it uses rolling torque ,thats slightly different. you`ll know when you take it apart.
 
achris

achris

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Re: Stern drive leak

I have a couple of videos in the stickies that might help you. Once the drive is off you can remove the yoke and drive gear assembly from the front of the drive-shaft housing. That does require the use of a special SPANNER.

Once you have the yoke assembly out you have a couple of options.
1. Pull the assembly apart and replace the seal yourself. Again a couple of special tools and a bunch of special procedures are required. And since it's a Gen II you'll need to set the rolling torque of the bearing assembly as part of the procedure.
2. Take that assembly to a shop and have them do it. The downside of this option is you don't have control of how and what is done, you just have to trust them.

Chris........
 
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Malibu496

Malibu496

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Re: Stern drive leak

Where do I find the stickies everyone talks about? Sorry new to the site I appreciate y'all's patience... Wife wants me to have this thing fixed like yesterday and it's my first boat...
 
Malibu496

Malibu496

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Re: Stern drive leak

I've got to change bellows, gimble bearing and that input seal while I'm in there... What tools besides the spanner wrench will I need? Have all the parts.. Came with boat when I bought it
 
M

MarkSee

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Re: Stern drive leak

Right at the top of this forum where you started the thread under the words:
Title / Thread Starter
You'll see threads that have the word: STICKY:

Click on that and find more to read than you can imagine that Don gathered over the years.

Since you have a 97 we'll assume that is the year of the drive and is indeed a gen 2 so find the sections on replacing the parts you want to replace and it'll show what tools are needed:
Boatinfo - Mercruiser Service Manual nr. 14 - 1991-Current - Sterndrives Alpha One Gen II</

Mark
 
achris

achris

More fish than mountain goat
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Re: Stern drive leak

Malibu496 said:
Where do I find the stickies everyone talks about? Sorry new to the site I appreciate y'all's patience... Wife wants me to have this thing fixed like yesterday and it's my first boat...
Click to expand...

Make a deal with the wife. You'll stay out of the kitchen if she stays out of the shed....

First rule with servicing/repairing boats... DO NOT RUSH! I've done a few hundred of these jobs, and the thing that will come back and bite you hard is trying to rush the job and get it finished quickly.. That will only lead to tears... Take your time, check everything twice and make sure you only have to do the job once. And that's the quickest way to get it done.

If you are going to replace the seal yourself, you'll also need a inch-pound torque indicator, and a press (or something similar).
BEFORE YOU START... Read the instructions, twice. When you're done reading them and you understand what you are doing, read them again....

Chris......

Here's a link to my videos. I have one on setting up the bearing preload...

http://forums.iboats.com/mercruiser-i-o-inboard-engines-outdrives/couple-new-videos-590378.html
 
Malibu496

Malibu496

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Re: Stern drive leak

Holy moly y'all are a huge help!! Thanks. Ill look into the sections.. Gonna tear it down tomorrow... And as far as getting in a hurry.. I did that the last time I put my race motor together and it was a 1500 dollar lesson.... It's how we learn.. Mistakes.. Taking my time
 
Malibu496

Malibu496

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Jul 7, 2013
Messages
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Re: Stern drive leak

Pulled the stern drive and the bellows were covered in oil mixed with water.. Found a seal that had dried and was breaking apart... As stated before I'm changing the bellows, Gimble bearing and gasket seals basically rebuilding it all back there...
 
R

Rob_NC

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Aug 10, 2009
Messages
26
Re: Stern drive leak

...just finished with mine..the input seal of the upper unit....check those bearings !..ujoints and coupler alignment ...proper setting of the bearing preload is a must..rolling torque
 
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Malibu496

Malibu496

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Jul 7, 2013
Messages
34
Re: Stern drive leak

Got it all torn down to the point where I need to remove the shift cable from the housing,.. I understand you need a really deep socket.. But my gen 2 has the plastic shift engager on the end of the cable.. Don't know how to get the plastic off the cable and get to the nut to remove it..got a pic if needed.
 
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