Oil leaking from lower unit drain.

Coastal Confessions

Coastal Confessions

New Member
May 28, 2012
108
Upstate NY
Boat Info
1994 Sundancer 300DA
Engines
Twin 5.7l Mercruiser with Alpha one gen II
1988 Sea Ray 268 Sundancer with twin 4.3s. After taking the boat out of the water to winterize it at home, I lowered both lower units to be sure they were drained. On the starboard unit, the starboard side of it, just above the horizontal shaft to the prop, toward the front of the unit is a tiny....... ohhhhh maybe 1/8 hole that appears to be a drain. (I say that because the port side was draining water from that spot when it was lowered) I noted sand plugging the hole. I cleaned it out with a wire then blew into it (no my boat didn't go oh baby LOL, but we are "good friends") there was resistance at first but the more I blew into it the easier it got and eventually water drained out. It sounds to me like the air was blowing up into the impeller of water pump. About an hr later there was contaminated oil coming out, chocolate milk looking, slow oooz. Is this BAD or do I just have a bad seal on something minor?
 
Are you and your boat on a first name bases or do you have to buy it dinner & drinks lol sorry just have to laugh in the summer my wife tells me I cheat on her with my ( our ) boat
 
ksimmons said:
Are you and your boat on a first name bases or do you have to buy it dinner & drinks lol sorry just have to laugh in the summer my wife tells me I cheat on her with my ( our ) boat
Click to expand...

:lol: Oh definitly, we've had dinner together, drinks together, late night swims. Infact, my wifefigure (were not married, her girls call me her husband figure lol) is even with us most of the time. Its an "open relationship" :thumbsup: (god we boaters are messed up)
 
On the leading edge of the drive there is a small hole like you describe where the pilot tube for the speedo connects, but it doesn't exactly sound like you are describing this area.

Is the hole on a flat wide surface of the drive, or on the leading edge where the drive comes to a point?

Can you post a picture?

Did your speedo work before?
 
I don't know for sure about 1988 era drives but what the OP describes sounds like one of the water drain holes that I know more recent drives have. For sure anyone that encounters freezing temps with boat out of the water should know where they are and make sure they're not blocked. You other guys have the drain holes. If you look in your manual it'll show their location.

For the OP, who knows how long that hole was plugged. If the amount of 'chocolate milk' is quite small it could be an accumulation of drops over many years and I wouldn't worry to much about it. Let it drain, then watch your gearlube level closely and watch to see how much more oil leaks out that hole.
 
The OEM Speedo is a vacuum type mounted to the Stearn as far as I know. It looks like all the other stern mounted ones I've had in the past. I have NOT drained the lower unit oil but intend to in the spring. It is my first year with this boat so I'm learning its specifics. I do not have a manual. I need to figure out just what drive it has. My assumption based on Internet research is that its an Alpha 1. Not sure which generation. Spring time I plan on sanding them both down and repainting them. They have layers of old black paint on them. They were originally white with Sea Ray stickers from what I can see.

It was a small amount of oil. Less than a cup. The other drive did not have any sand in that area, although I know both motors were fired up one or twice in shallow sandy water to charge the batteries so I wasn't surprised.

The hole I am speaking of is not on a flat area, it is in part of the curve the the horizontal shaft of the propeller.
 
http://www.scribd.com/doc/39660594/Mercruiser-Owners-Manual Take a look at the pic on page 76. The lower left red line points toward the speedo pickup hole, it's right on the knife edge. The other lines are toward possible drain holes. There can be other holes down there also, not shown in that pic but you can see them on page 83. Maybe it'll help you describe which hole you mean.
 
Cool, thanks for the link. Nope def not a speedo tube. The hole is on the side and lower.
 
Coastal Confessions said:
Cool, thanks for the link. Nope def not a speedo tube. The hole is on the side and lower.
Click to expand...

Id say ANY milky brown oil coming out of any hole on the OD is bad. You need to drain the drive and see if the oil coming out is milky. If it is, you need to get the water out of there ASAP and get the drive resealed. Water will quickly destroy the gears in there, and that can get expensive.
 
Coastal Confessions said:
Cool, thanks for the link. Nope def not a speedo tube. The hole is on the side and lower.
Click to expand...

The hole you describe is a water drain hole. As others have stated, if you have oil coming out of that hole, there is a bad seal somewhere in the outdrive that needs to be replaced.
 
Coastal Confessions said:
The OEM Speedo is a vacuum type mounted to the Stearn as far as I know. It looks like all the other stern mounted ones I've had in the past. I have NOT drained the lower unit oil but intend to in the spring. It is my first year with this boat so I'm learning its specifics. I do not have a manual. I need to figure out just what drive it has. My assumption based on Internet research is that its an Alpha 1. Not sure which generation. Spring time I plan on sanding them both down and repainting them. They have layers of old black paint on them. They were originally white with Sea Ray stickers from what I can see.

It was a small amount of oil. Less than a cup. The other drive did not have any sand in that area, although I know both motors were fired up one or twice in shallow sandy water to charge the batteries so I wasn't surprised.

The hole I am speaking of is not on a flat area, it is in part of the curve the the horizontal shaft of the propeller.
Click to expand...
WORD OF ADVISE....
don't wait till spring...if there is water in your lower ...and there probably is... it can freeze and crack the case
changing from a 800.00 rebuild to a 3-5k replacement
if the oil is getting out there is more than likely water getting in also.
 
I finally got a picture. Here is where the slow slight leak is coming form.
tn.jpg
 
I would look to the shift shaft seal or the water pump carrier seal/the seal/housing thats located under the water pump housing. This part is included in a full water pump repair kit.
 
Am I correct in thinking it just a drain from the water pump. Not sure if you read my original post, It was plugged with sand. Once I cleared it out I got water followed by oil. I intend on replacing the water pump with a kit. So it sounds like the seal I need will be in it?
 
Correct, it's a water drain hole, the seal is called a drive shaft carrier seal and is located under the water pump SS rub plate, if you order the kit, try Basicpower.com, they are good folks over there and decent prices. The carrier housing/seal just slides down over the drive shaft after you separate the upper and lower halfs of the drive, PM me if you like and I'll talk you thru it if ya need it.
 
Problem fixed. We originally thought it was the shift linkage seal located behind the water pump in the lower half of the drive. Got it all back together and it still leaked. So I figured it was the top end. Replaced all the seals in the top end and no leaks. :)... here are some pics101 (1).jpg101 (2).jpg101 (7).jpg101 (8).jpg101 (9).jpg101 (10).jpg101 (11).jpg
 
No. Was pretty confident it was in the lower end. When I found out it wasn't, it was only $25 for the top end seal kit so I said why not just reseal the top to. If it still leaked I would have pressure tested it. When I bought the boat last year I was told both drives had been resealed. As you can see in one of the pics, I think the seal got damaged when installed. It was so easy that next year Ill reseal the port side.
 
You must log in or register to reply here.

Forum statistics

Threads
113,190
Messages
1,428,252
Members
61,100
Latest member
Raneyd85
Back
Top