Lower unit oil loss from res. [Archive]

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ALM

10-26-2009, 11:30 AM

MOBILEMERCMAN

10-26-2009, 11:39 AM

I would suggest cleaning the hose and all fittings well and check after each use.

You said all seals are good. Has the drive been off and serviced recently? If the yoke seal is leaking it will leak into the bellows and eventually into the bilge. I would think if the hose was leaking outside the transom there would be water mixing in the lube.

ALM

10-26-2009, 11:55 AM

Geronimo36

10-26-2009, 02:06 PM

I loose lower unit lube from the reservoir. Some goes in the bilge, but I see no oil route. Some seems to get out by the outdrive, under the rubber hoses.
I seen and felt the oil when I flushed. Outrdive seals are good, no oil leaks. Unit has lube all the way up to the top vent hole.
I know there is a tube that goes through from the reservoir to the outrdive. How do I check the connection?
525, ITS Bravo XR.

Couple things to check;

1. You said there is oil in the bilge? It may be coming in thru the driveshaft opening and if that's the case you ahve a bad upper seal.

2. You said there seems to be oil coming from under the rubber hoses? (bellows). This could be from oil reseviour hose/fittings that go from the transom assembly to the gimbal helmet. It's a small hose and it's held in place by plastic clips that are prone to breaking over time. Lift up the drive all the way and visually inspect the hose, it will attach to the helmet on the right hand side, follow the hose to the transom assembly and check for oil leaks. The hose itself may even have a pin-hole.

3. May also have a bad o-ring between the drive and helmet mating surfaces. When people install the drive they sometimes misalign the o-ring or don't use adhesive to hold it in place.

4. The small o-ring in the top cap of the drive might be pinched.

Just a few suggestions, hope this helps!

ALM

10-27-2009, 03:48 PM

I trimmed it up, looked and felt all around. Did not see or felt any small tube. Must be inside the rubber bellows. There is oil around the bellows. etc.
Never removed a Bravo before. Worked on Alphas. Quick comments on outrdive removal?
Gear in forward? etc.? Anything I should know before I remove it and check the bellows and tubes?

Geronimo36

10-27-2009, 03:58 PM

There is a small hose that goes from the outside of the transom assembly to the bellhousing. If you're looking at the back of the boat it's on the right-hand side somewhat even with the hinge-pin. Merc doesn't have good pictures but if I remember the hose is roughly 3/8".
http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=891749001&ivar=images/COMMON/5849.png&inbr=11406&bnbr=250&bdesc=Gear+Lube+Monitor+Components
http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=891749001&ivar=images/COMMON/5476.png&inbr=11406&bnbr=110&bdesc=Bell+Housing

You don't need to put it in Forward like an Alpha, just unbolt and pull it off. There is a claw-like fitting on the right hand side that when you pull the drive back it opens up to allow unhooking of the shift cable. Actually, just above the shift cable is where the remote oil fitting is.

ALM

11-01-2009, 06:58 PM

Removed the outdrive. There was gear lube in the bellows and under it. Just above the anode. (see pic. tip of scre driver)
Where does it come from? O rings and seals seemd to be ok.
I saw the end of the oil tube with a little valve on it, and there was a ball in the outdrive where it connects. I think they act like a valve. There is an o ring around the connection but looked ok. Drained the lower unit. Oil is good. No shavings or water, so I guess it's the reservoir system or tube issue. Any ideas how to fix?
45065

MOBILEMERCMAN

11-01-2009, 08:00 PM

ALM

11-01-2009, 08:17 PM

I say drain and pressure check the drive.. You are most likely going to find a leaking input shaft { yoke seal } leaking. I would suggest you bring it to a shop. There are a few special tools needed to repair this.
The lube was in the bellows and spilled out as you removed the drive.
If the boat is 5 to 7 years old the bellows are due to be changed.

Thanks Jim, but the oil in the bellows was not from spilling during removal.
There was no oil in the reservoir and I slid the drive out easily and quick. I made a track so I can slide it out. I also drained some of the oil from the lower unit. I can assure you it was not from the removal process. There were way too much oil in the bellows from a few seconds of slippin the drive out out time. The boat/motor is only 2+ year old. I'm not sure what you mean by " yoke seal " leak. The shaft and everything around it is ok. I can do a preassure check. I have the tools to do it and will do it Monday PM. I don't think it's "drive leak". Seems to be something with the reservoir tube and conection to the outdrive. But not sure.

MOBILEMERCMAN

11-01-2009, 08:25 PM

I am saying the lube in the bellows can only get in there if the yoke seal { input shaft } is leaking..The lube you mentioned on the anode is from removing it.. If you could see lube on the bellows before you removed it I would think the bellows is on its way out or you have 2 leaks.. Typically they last more than 2 years.. The yoke seals leak it is not un common. The seals also wear grooves in the yoke... There is no way to determine it visually. The only way is pressure checkng the drive.. I would bet you lunch it is the yoke seal if I lived near by.

If you have the spanner wrench, drive stand, some drivers, a roller torque inch/lb wrench it is a simple repair.

2112

11-01-2009, 09:02 PM

There are a few special tools needed to repair this.

.

Is it hard to swap out the yoke seal/input shaft assembly? The seal is an O-ring, correct?
.

MOBILEMERCMAN

11-01-2009, 09:10 PM

If you have the spanner wrench, drive stand, some drivers, a roller torque inch/lb wrench it is a simple repair.

In addition to these you will need basic hand tools and a torque wrench. There are some specific procedures and specs to follow. Rolling torque on bearings. If by chance you over tighten them you will need a press and jaws to loosen before continuing. You will need to ensure the timing marks on the driven gears are timed correctly. You need to measure your torque wrench and spanner wrench to calculate the proper value on torque wrench to achieve 200ft/lbs.

Michael the service manual I previously mentioned to you has all of this and more.

MOBILEMERCMAN

11-01-2009, 09:18 PM

Is it hard to swap out the yoke seal/input shaft assembly? The seal is an O-ring, correct?
.

There is an O ring and a seal. Its the seal that is doing all the work. It rides on the spinning shaft.. The o ring is sealing the housing to the cover nut and related pieces.

It is easier than changing a bellows. Just requires a different set of tools. Once the drive is off it typically takes about an hour. The variable is when you correct one leak and pressure check you may find another. On an older drive you may as well change all the seals. I believe the flat rate on that is 3.5 hours on the upper. Of course a few more tools too .

2112

11-01-2009, 09:48 PM

Which manual should I get and where do you suggest I get it? I have one but it is old and not an official Merc manual so some details are missing.
.

ALM

11-01-2009, 09:58 PM

MOBILEMERCMAN

11-01-2009, 10:12 PM

Which manual should I get and where do you suggest I get it? I have one but it is old and not an official Merc manual so some details are missing.
.

You can order one at any Mercruiser dealer. The drive is a different manula than the motor.

MOBILEMERCMAN

11-01-2009, 10:16 PM

Not knowing the actual term. What is the yoke seal? Have a picture? Are you talking about the upper drive shaft/U joint shaft that goes into the upper drive housing? Is that the "yoke" you referencing?

Yes, the yoke is the piece that holds the u joint and enters the drive housing. It is the seal that rides on the yoke that is likely to be your problem.

http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=891748001&ivar=images/COMMON/26416.png&inbr=11296&bnbr=110&bdesc=Universal+Joint+and+Shift+Components

25 is the yoke 28 is the seal. Its all there

Geronimo36

11-01-2009, 10:19 PM

Couple things to check;

1. You said there is oil in the bilge? It may be coming in thru the driveshaft opening and if that's the case you ahve a bad upper seal.

Removed the outdrive. There was gear lube in the bellows and under it. Just above the anode. (see pic. tip of scre driver)
Where does it come from?

I say drain and pressure check the drive.. You are most likely going to find a leaking input shaft { yoke seal } leaking. I would suggest you bring it to a shop. There are a few special tools needed to repair this.

The lube was in the bellows and spilled out as you removed the drive.

If the boat is 5 to 7 years old the bellows are due to be changed.[B]

[B]Thanks Jim, but the oil in the bellows was not from spilling during removal.

There were way too much oil in the bellows from a few seconds of slippin the drive out out time.

I am saying the lube in the bellows can only get in there if the yoke seal { input shaft } is leaking..The lube you mentioned on the anode is from removing it.. If you could see lube on the bellows before you removed it I would think the bellows is on its way out or you have 2 leaks.. Typically they last more than 2 years.. The yoke seals leak it is not un common. The seals also wear grooves in the yoke... There is no way to determine it visually. The only way is pressure checkng the drive.. I would bet you lunch it is the yoke seal if I lived near by.

If you have the spanner wrench, drive stand, some drivers, a roller torque inch/lb wrench it is a simple repair.

There is an O ring and a seal. Its the seal that is doing all the work. It rides on the spinning shaft.. The o ring is sealing the housing to the cover nut and related pieces.

It is easier than changing a bellows. Just requires a different set of tools. Once the drive is off it typically takes about an hour. The variable is when you correct one leak and pressure check you may find another. On an older drive you may as well change all the seals. I believe the flat rate on that is 3.5 hours on the upper. Of course a few more tools too .

Not knowing the actual term. What is the yoke seal? Have a picture? Are you talking about the upper drive shaft/U joint shaft that goes into the upper drive housing? Is that the "yoke" you referencing?

Yoke seal is also known to some as an upper seal. the seal is located behind the yoke (u-joint and socket assembly) when it it's held into the drive by a spanner nut.

When the drive is on the boat that bellows area gets sealed by the drive housing and when the seal goes bad all the oil collects in the bellows area. When you remove the drive it oozes out..

You mentioned there was oil in the boat, I had suggested the upper seal (Yoke) was bad in my first post! ;)

MOBILEMERCMAN

11-01-2009, 10:21 PM

You mentioned there was oil in the boat, I had suggested the upper seal (Yoke) was bad in my first post! ;)

Frank we agree again. I was first:):sifone:

2112

11-01-2009, 10:26 PM

You can order one at any Mercruiser dealer. The drive is a different manula than the motor.

Yeah, Mine is a SELOC aftermarket manual. Not so great. :(
.

MOBILEMERCMAN

11-01-2009, 10:29 PM

Geronimo36

11-01-2009, 10:30 PM

Frank we agree again. I was first:):sifone:
You're on it again!!!! :blush5:

If he's going to attempt to do it by himself he'll also need the seal driver. The yoke seal is pressed into place and it's pressed in slightly more than flush. If the seal is pressed in flush the face of the seal will rub up against the yoke and wear a hole thru it.

How do I know this? Well, many years ago a customer had a poker run planned and a day before the poker run he called and said there's oil in the bilge.. So I pull the drive and find it's the yoke seal. So I get it apart and come to find out we don't have any yoke's in stock and the merc dealership up the street (Freddie) doesn't have any yokes either...

So I call up the customer and let him know we can't get a yoke and he needs one and asks me to do whatever I can to get him running and we'll fix it on Monday.

So, I install the yoke seal slightly higher to attempt to allow the lip of the seal to ride on a clean part of the yoke... I put it together and pressure checked perfect.. Even went for a test run and it ran perfectly...

He called me half way thru the poker run saying the drive resevior is low again... so I'm like chit, WTF, everything checked out perfect.... So he runs the rest of the poker run and adds some oil at the card stops..

He got back from the run without any issue but on monday I pulled the drive and when to install the new yoke we had on order, only to realize the seal face had a hole worn thru it....:ack2:

Lesson in all this... Don't try to get away with it, even if the customer asks you too!! And for the others, make sure you have the seal driver so it doesn't happen to you!:seeya:

2112

11-01-2009, 11:29 PM

I think the selocs are pretty much useless by comparison.

I think that is an understatement :ack2:

Sent you another P/M BTW if you see this 1st.

I am glad we are finally getting the tech section rockin here on SOS! :sifone:
.

2112

11-01-2009, 11:41 PM

You're on it again!!!! :blush5:

If he's going to attempt to do it by himself he'll also need the seal driver. The yoke seal is pressed into place and it's pressed in slightly more than flush. If the seal is pressed in flush the face of the seal will rub up against the yoke and wear a hole thru it.

Lesson in all this... Don't try to get away with it, even if the customer asks you too!! And for the others, make sure you have the seal driver so it doesn't happen to you!:seeya:

Great info;

Here are pictures of a new yoke seal and anodized cover, front and back.

If I read you right, you meant the seal we see in the center of this unit needs to be less than flush?

.

Geronimo36

11-02-2009, 12:14 AM

yeah, on the back part the cover (spanner wrench holes) the seal should be driven in slightly more than flush. the seal driver that's made for it drives it in, if I had to guess, roughly 20-30 thou more than flush. that's the new XR style cover, the older ones had a seperate plate and retainer nut along with a different seal.

2112

11-02-2009, 01:04 AM

Boy, It appears to be flush now and that is straight from Mercury! :eek:
.

ALM

11-02-2009, 09:17 AM

Yes, the yoke is the piece that holds the u joint and enters the drive housing. It is the seal that rides on the yoke that is likely to be your problem.

http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=891748001&ivar=images/COMMON/26416.png&inbr=11296&bnbr=110&bdesc=Universal+Joint+and+Shift+Components

25 is the yoke 28 is the seal. Its all there

Thanks.. That's what I thought. I went to BAM site and looked at it also. I just wanted to be sure I understand the right terms. If it is my yoke seal, I won't do it mysefl. I will preassure check later today.
I might have to send you a lunch coupon.

Geronimo36

11-02-2009, 10:19 AM

Boy, It appears to be flush now and that is straight from Mercury! :eek:
.

Jimmy will know more on this but it's possible the newer XR yoke seal doesn't drive in further anymore. It's a different seal and a different yoke than the older XR's with the smaller U-joints and the std. bravo. The design changed.

The larger u-joint assembly came out after I changed careers so I could be dating myself so let's see what Jimmy says about the new ones.

PARADOX

11-02-2009, 10:38 AM

Good info.

Can I pressure check the outdrive while in place? or it has to be removed? What pressure should I put on to test. I have a leak down test kit, that I think I can use.
THX
P

Geronimo36

11-02-2009, 11:03 AM

Can't pressure check on the boat unless you pinch or plug the drive resevior hose which I never recommned...

Merc has a specific pressure/suction test proceedure which I vaguely remember the exact details. I seem think it was something like 10-12 psi for 10 minutes with a minimum % drop over time (1-2 psi max drop)???? (I'd have to double check the book for exact figures). I've found they're either good or bad, not so much inbetween.

Basically, you put in 10-12 psi and if it starts dropping off you need to re-seal... Most of the time the leak is from pressure not suction but test both to be sure.

MOBILEMERCMAN

11-02-2009, 11:32 AM

Jimmy will know more on this but it's possible the newer XR yoke seal doesn't drive in further anymore. It's a different seal and a different yoke than the older XR's with the smaller U-joints and the std. bravo. The design changed.

The larger u-joint assembly came out after I changed careers so I could be dating myself so let's see what Jimmy says about the new ones.

I can't comment on the newest. The driver number is 91-813683T and as Frank mentioned it positions the seal in about .020.

On the early standard Bravos flush was OK. You can position them further in once or twice to avoid the ring groove that forms.

Its the X XR XZ that are different. They carry the seal in the cover nut. The standard the seal rides in a spacer piece.

MOBILEMERCMAN

11-02-2009, 11:36 AM

Merc has a specific pressure/suction test proceedure which I vaguely remember the exact details. I seem think it was something like 10-12 psi for 10 minutes with a minimum % drop over time (1-2 psi max drop)???? (I'd have to double check the book for exact figures). I've found they're either good or bad, not so much inbetween.

Basically, you put in 10-12 psi and if it starts dropping off you need to re-seal... Most of the time the leak is from pressure not suction but test both to be sure.

I test to 14 lbs. with no drop. If it sits over night it may drop from cooling other than that I seek no drop and prefer to let sit for 30 minutes. Sometimes that is not practical but that is my preference.

2112

11-02-2009, 09:18 PM

I would guess the Merc Manual is about 90 dollars. They should sell it to you. Some places are weird and may make a big deal out of it. I can give you the part number tomorrow if needed. I think the selocs are pretty much useless by comparison.

Bought it today.

Wow, what an extremely nice shop manual. The Seloc is going straight into the recycle bin.

I took my drive down to have the upper shaft assembly replaced. They said it is about a 1 hour job barring any unforeseen problems.

.

ALM

11-05-2009, 02:54 PM

Mobil man. You got lunch comming. I just tested the drive. Put in about 12 - 14 pounds and I heared air coming at the seal.
I got to take this to get it fixed. :(

MOBILEMERCMAN

11-05-2009, 02:58 PM

Glad I could help....

That's what we do here. Help each other.

Geronimo36

11-05-2009, 05:29 PM

Mobil man. You got lunch comming. I just tested the drive. Put in about 12 - 14 pounds and I heared air coming at the seal.
I got to take this to get it fixed. :(

This is a good time to reseal the complete upper. Next year you might pull the drive off and find oil in the shift cable cavity, coming from the shift shaft seal. Also a good time to check all the gears/bearings....

The labor to dissasemble the upper gear/yoke and replace the yoke seal (possibly even a new yoke) combined with the cost of a single seal vs. a seal kit is somewhat close so I'd just do the whole upper while you have it off and apart.:driving:

ALM

11-05-2009, 07:56 PM

Great. thanks. more $hit to deal with?
Merc men needs to bring his tools to the Keys. I bring the drive.

MOBILEMERCMAN

11-05-2009, 09:10 PM

Sorry Alex, I went the last couple years. I will not be going this year. Resealing is basic work any dealer should be able to turn it over for you quick.