leak in lower unit

al1026

Petty Officer 2nd Class
Joined
May 17, 2007
Messages
101
I have an alpha 1.On a 1984 sea ray 488 merc 4 cylinder engine. Last year I had the rubber hoses changed in lower unit.I had a driveway mechanic that said the hoses are original and if a split occures boat could sink.
Mechanic changed, A few week later I used boat and when I was tied up at dock boat ramp and I was checking oil I heard a drip drip sound coming from the rear housing inside engine compartment .Not sure if the drip was happening prior to hoses being changed.? This mechanic is a driveway guy tried asking him about this but after 5 calls and never returning any calls, so I gave up.
I live in Floirda and use boat often. Have been living with this issue almost two years. Boat is at my home. Engine area is tight and can't see were water is coming in from, but can hear drip drip sound. And then there are times when I don't hear the drip
Can't tell how much water is entering within the hour not seems not very much except driving me crazy
I understand With out seeing almost imposible to zero in.But what do you guys think could be causing this drip .
Thought bolts holding the gimbel housing could have rusted?allowing water to enter?Besides the two hoses the mechanic changed are there any more rubber hoses in lower unit that could could cause this??Maybe defective hoses??
This year I had another driveway mechanic change impella in lower unit and he eye balled said the hoses seemed fine??? To find out what the leak he felt there was a possiblity the engine had to be removed.
So fellow boater anybody had a simuliar problem and any ideas what else I should look for????? any some sort of pressure test ??
I stay off shore or intracoastal . Only use few hours at a time and then I trailer home.
Recently left over night at a marinia and stayed up all night wondering if bildge would go on or upon early arrival I could find 3 ft of water on engine room. WHen I got down everything was fine but battery was weak which indicated pump went on often during the night.
Happy boating
Thanks
al in Orlando
 

captmello

Captain
Joined
Jun 30, 2008
Messages
3,848
Re: leak in lower unit

Hard to say. Your going to have to get your head in there and find it. When its dripping, run your hand around the area you think it may be coming from. Start at the top and work your way down until you find some wetness. Towel off the area first if you can. You may need to move some seats or interior pieces to get in there but its the only way to find out. It sounds like it drips whether the engine is running or not, Right?
 

al1026

Petty Officer 2nd Class
Joined
May 17, 2007
Messages
101
Re: leak in lower unit

Hard to say. Your going to have to get your head in there and find it. When its dripping, run your hand around the area you think it may be coming from. Start at the top and work your way down until you find some wetness. Towel off the area first if you can. You may need to move some seats or interior pieces to get in there but its the only way to find out. It sounds like it drips whether the engine is running or not, Right?
Thats for getting back. Position of engine makes it impossible to get to back of engine. Laying on my stomach Can get a small look at rear and try to feel to find leak but almost impossible to pin point
WHile emailing back to you it dawned on me that there is holding bins that basically cover the engine room. Storage for fishing gear . Twin doors that cover engine room.A major task to disassemble but if I do I can get more access to rear. WHen this is taken apart if need to be the engine can come out of boat. Otherwise working in this engine room is not mechanic friendly. I ran a bead of marine corking around gimbel housing out side and this did not help
Too your knowledge are there more hoses than the two the guy changed.
Not sure of the name of hose but when looking at lower unit can see a wide rubber hose.
Thanks for getting back captain
 

chiefalen

Captain
Joined
May 18, 2008
Messages
3,598
Re: leak in lower unit

Get that bilge 100 percent dry.

And lay newspaper down under the motor. Put the boat in the water.

And with a flashlight watch for the drips.

You will at least narrow down where the first few drips are coming from.

Might not be the transom, might be something else.

Like the elbow, exchanger, only the shadow knows for sure.

Good luck keep us posted.
 

ziggy

Admiral
Joined
Jun 30, 2004
Messages
7,473
Re: leak in lower unit

there's only one hose on your drive. the water hose that connects the drive to the transom shield. this hose would not leak water into yer boat. however the tube that passes thru the transom shield could i believe. there are three bellows in the drive though. the larger main drive shaft bellows. the smaller exhaust bellows directly below the drive shaft bellows, and the small shift cable bellows that is starboard of the main bellows and the exhaust bellows. the drive shaft bellows and the shift cable bellows can leak water into your boat if not sealed. the exhaust bellows is irrelevant as there's water in the exhaust system up to the water line while the boat is static in the water. on the inside of the boat where the exhust pipe mounts to the gimble housing there is a seal though. it's under water all the time so it could leak. the gimble housing could also leak water into the boat if it wasn't sealed to the transom. or if wood rot has effected the gimble housing seal.
sounds like a bummer to work in your bilge for no room to work. along with the other suggestions. i'll through out using a mirror or using a camera to see places you can't get to...

do you have a service manual? there's pics in it + proper terminology to call parts in your boat....... this could be helpful in discussion since we only have words to communicate...
 

freeone

Petty Officer 2nd Class
Joined
Aug 10, 2007
Messages
104
Re: leak in lower unit

there is a junction at the bottom of the gimball ring where the hydraulic lines for the trim rams connect. there is a seal between the junction an the gimbal ring check for corrosion. two hoses from the pump go through the transom and connect to the junction inside the gimbal behind the junction. i believe that seal at the junction is the only thing stopping water from getting in the bilge.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,090
Re: leak in lower unit

and when I was tied up at dock boat ramp and I was checking oil I heard a drip drip sound coming from the rear housing inside engine compartment .Not sure if the drip was happening prior to hoses being changed.? Engine area is tight and can't see were water is coming in from, but can hear drip drip sound. And then there are times when I don't hear the drip. I understand With out seeing almost imposible to zero in.But what do you guys think could be causing this drip.

Ayuh,...

You're Right,.... You're the only 1 who can See, but more importantly, Hear the Drip....

1st Clue is,... You Hear a Drip,... That means it's coming from above,+ Not below,...
That'll rule out the Hyd. Manifold mentioned by Freeone... That'll Seep, not drip...

When you can Hear the Drip,.... Start Looking..... Follow the Sound....
That might mean you might have to take 1/2 of the boat apart to get a Look,+ more importantly, a Feel...
That's the Only way it's going to be Found,+ then fixed....

Your boat is a Hole in the Water,+ the Water will try to get in Everywhere it touches...
There are Many places it can get in, in the driveline,...
Bellows, Hoses, Exhaust fittings, even the Transom itself...
If you, yourself are Unable to do this,... you'll have to bring along somebody to help...
Just the fact that you can Hear it, should make it a reasonably Easy find....
 

billder62

Seaman Apprentice
Joined
Nov 13, 2007
Messages
33
Re: leak in lower unit

I have used a telescoping inspection mirror and flashlight when I cant get my head in there , great help.
 
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