3.0L Mercruiser mysterious hose/tube

Joined
May 29, 2012
Messages
17
So long story short, my wife and I were handed down a 1995 Bayliner Capri 1750 with the 3.0L Mercruiser and Alpha 1 (gen 2 I believe). Anyway, when we got it, there was water in the oil. So after a few oil changes we hit the lake for a quick cruise so see if we had any real problems. Luckily it looks like it was simply water that snuck in while the boat sat for a couple years.

Anyway, after pulling the boat out of the water I noticed that the bilge had what looked and smelled more like gear oil/lube than motor oil. Not a lot of it, but enough to make you notice. I believe I've traced the culprit down to the mysterious hose pictured the below. The hose runs back to the transom and is connected to what feels like harder tubing/pipe (hard to see exactly). However, I can't for the life of me figure out if the end pictured is supposed to be connected to something else or if it is some sort of vent. I know some outdrives have a separate reservoir for gear oil.

Thanks in advance for the help.

The first pic shows the hose as it sits on starboard side as your looking towards the rear of the boat. Second pic attempts to show its path back to the transom.

12 - 1.jpg12 - 2.jpg
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: 3.0L Mercruiser mysterious hose/tube

If that's the leg oil monitor it should be connected to a bottle, mounted somewhere on the engine...

Chris....
 

tmhelvie1982

Recruit
Joined
Feb 24, 2012
Messages
3
Re: 3.0L Mercruiser mysterious hose/tube

That looks like the hose that would connect to your resevoir.. On my 3.0 I have a resevior attached on the starboard side of engine, my old 3.0 did not. Could you take a pic of the front of your engine. That would tell us alot or give us some serial numbers.
 
Joined
May 29, 2012
Messages
17
Re: 3.0L Mercruiser mysterious hose/tube

If that's the leg oil monitor it should be connected to a bottle, mounted somewhere on the engine...

Chris....

That was my thought but I haven't found such a bottle. I'll take some more pics and post more info in the am.
 
Joined
May 29, 2012
Messages
17
Re: 3.0L Mercruiser mysterious hose/tube

That looks like the hose that would connect to your resevoir.. On my 3.0 I have a resevior attached on the starboard side of engine, my old 3.0 did not. Could you take a pic of the front of your engine. That would tell us alot or give us some serial numbers.

So I took some pics.

Here's my serial# info: IMG_1735.jpg

and pics of the engine and reservoir bracket(?):
IMG_1737.jpgIMG_1739.jpg


So it certainly looks to me that it had a reservoir at one point. My question now is if that is something that is necessary to replace or can I simply plug/cap the hose and not worry about it?

Thanks again for the help.
 

tommy8604

Cadet
Joined
May 29, 2012
Messages
28
Re: 3.0L Mercruiser mysterious hose/tube

i would say that is your reservoir bracket. as far as capping it off i would say you could but you would have to keep a close eye on you outdrive oil level as the reservoir would show you the oil level and also supplied oil incase of some leaking out.
 

Utahboatnut

Senior Chief Petty Officer
Joined
Jan 15, 2009
Messages
785
Re: 3.0L Mercruiser mysterious hose/tube

i would also keep a very close eye on the oil issue usually that much water doesnt just sneak into an engine after a few years unless it has sat with the engine cover off and the flame arrestor and cover gone. the cover could have had a leak and allowed water in and might not be anything but for sure keep an eye on it..
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: 3.0L Mercruiser mysterious hose/tube

Yes you could cap it off... But, Merc put them there for a reason, and that reason is to reduce the damage done when you get a leak, either water in or oil out (because it connects into the alarm circuit. Those 2 wires hanging near the bracket)... I would bite the bullet and buy a new bottle... It's WAAAAYYYY cheaper than a new drive...

Part# for the bottle... -806193A51 (about $90)

Chris......

EDIT: It's got me curious... Why would anyone take the bottle off?
 

81 Checkmate

Lieutenant
Joined
Jul 20, 2010
Messages
1,360
Re: 3.0L Mercruiser mysterious hose/tube

Im with Chris... pick up a new bottle and make it the way the factory made it. Like Chris said there is a reason for it.

Also i would check your outdrive gear lube as it is now... could be low or water intrusion. Just pull the drain plug and take a sample..
 

fishrdan

Admiral
Joined
Jan 25, 2008
Messages
6,989
Re: 3.0L Mercruiser mysterious hose/tube

A replacement bottle is cheaper than a replacement drive...

Since you have gear lube in the bilge, (it only came from one place) I would drain/refill the drive and look at the old oil for metal, or excessive metal. Check the upper unit's vent plug to see if it's low on lube first, so you know if it was run low on lube.
 
Joined
May 29, 2012
Messages
17
Re: 3.0L Mercruiser mysterious hose/tube

A replacement bottle is cheaper than a replacement drive...

Since you have gear lube in the bilge, (it only came from one place) I would drain/refill the drive and look at the old oil for metal, or excessive metal. Check the upper unit's vent plug to see if it's low on lube first, so you know if it was run low on lube.

Thanks for the help guys! I drained some gear lube and refilled it to check it prior to taking the boat out (everything looked fine). I also checked it again after I noticed it was leaking and everything still looks good. In reading more about how this all works I think that by refilling it until it came out the vent plug I inadvertently pushed oil out the house that should be connected to the nonexistent reservoir (I didn't really look in the bilge prior to setting out on the lake and it did seem as though I had to at a lot more oil then I drained when I checked it so I'm assuming I was just pushing it out the hose.)

Upon reading more I'm a little hesitant to just cap it off since part of the reservoirs purpose is to create/relieve pressure to prevent water from being sucked into the drive.

Before I bite the bullet and purchase a reservoir bottle is there anything else this hose could be for? I'm fairly confident we've correctly identified it but just want to double check.

Also, is this the kit I'd need? Gear Lube Bottle Kit, Mercury - Mercruiser 806193A48
 

fishrdan

Admiral
Joined
Jan 25, 2008
Messages
6,989
Re: 3.0L Mercruiser mysterious hose/tube

Before I bite the bullet and purchase a reservoir bottle is there anything else this hose could be for? I'm fairly confident we've correctly identified it but just want to double check.

To confirm, stick a Qtip in the hose and see if it comes out green/blue gear lube colored, I bet it does. The bracket, hose and wiring in the pic are correct for the bottle, just no bottle.

That P/N looks good, it comes with the rubber strap that you'll need too.

After installing the bottle, fill the drive from the bottom until the bottle starts filling, so you fill the hose and top off the drive. Then you can top off the bottle inside the boat. (Who knows how much lube was lost from the drive by having the bottle disconnected and running the boat...)
 
Joined
May 29, 2012
Messages
17
Re: 3.0L Mercruiser mysterious hose/tube

Thank's everyone for help! I went ahead and ordered myself the kit.

EDIT: It's got me curious... Why would anyone take the bottle off?

Your guess is as good as mine. We acquired the boat as a result of a sudden death in the family so the answer is likely to remain a mystery. Seeing as how there was water in the motor oil and trim pump (so far testing hasn't shown any leaks) I have a hunch that the boat filled with water at some point (or sat uncovered) and I'm wondering if the reservoir wasn't removed to empty obvious water sitting in it and never put back on.

Anyway, thanks again for all the advice/help. If you don't hear back from me on this issue assume that all is well and that I'm out making waves.
 

mikemurd

Recruit
Joined
Apr 17, 2010
Messages
3
Re: 3.0L Mercruiser mysterious hose/tube

I picked up a 1981 Bayliner Liberty with a Mercruiser 4 and some problems. First I have had a few Mercruisers and I have manuals but I have never seen this. Please see photo of blue plastic tube and gimbal housing.
PS I can't get the photo to upload
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: 3.0L Mercruiser mysterious hose/tube

I picked up a 1981 Bayliner Liberty with a Mercruiser 4 and some problems. First I have had a few Mercruisers and I have manuals but I have never seen this. Please see photo of blue plastic tube and gimbal housing.
PS I can't get the photo to upload

Please do not hijack a current thread.... Start your own and you'll get far more help...

Welcome to iBoats...
 
Top