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JKTX21
11-12-2006, 11:56 AM
So I go to hook up my boat yesterday afternoon, and pull it out only to discover that A LOT of my oil has leaked out into the bilge while sitting. There was minimal amount on the dipstick, maybe half an inch. The last time out I made certain to check the oil a couple of times during the day (as I just got it back from the shop), so it had oil.

I couldn't pinpoint the leak yesterday, has this happened to anyone? I felt around and the oil pan has clearance between it and the bolts for the bottom fins, so there's not a hole in the pan. Has anyone had their drain line crack or where it mounts to the pan fail? Thanks in advance.

JimN
11-12-2006, 12:26 PM
It's not going to leak out of the pan where it meets the block unless there's an excessive tilt AND the gasket or main seal is bad. Clean it out and lay some paper towels under it, fill the crankcase to a normal level and look for oil spots. That will tell you where the leak is. The fact that you checked the oil level a couple of time when you were out last tells me that you have had some leaks before. It is possible for the drain plug to be loose, the hose to crack or the seal where that attaches to go bad.

What was done at the shop that would make you worry about the oil level? If it didn't leak ebfore they worked on it and they did some disassembly near the oil pan, or at least under the top of the oil level, they should get it back. That's called a rework.

mrG
11-12-2006, 12:44 PM
Also, look around the flywheel area. If the main seal goes bad it can leak from the bottom of the bell housing.

JKTX21
11-12-2006, 01:03 PM
The reason I was checking the oil and keeping an eye on it last time out, the brass fitting for the oil pressure sending unit cracked and pumped out a bunch of oil. It was repaired and I kept an eye on it and the oil level, but all was okay with that.

JKTX21
11-12-2006, 01:08 PM
Also, my mechanic didn't do anything major, just had it in for a tune-up and new water pump. He is an individual and sees A LOT of tournament ski boats. He's going to take a look at it this week, I will update

mrG
11-12-2006, 01:09 PM
If you know that it's not leaking from the upper part of the engine like a valve cover or something like that, try feeling around under the engine with your hand. With that much oil in the bilge you should be able to find a concentration of fresh oil somewhere on the bottom surface of the engine.

TMCNo1
11-12-2006, 01:42 PM
Has the oil and filter been changed recently and is the gasket messed up on the oil filter, or is the cap leaking on the end of the oil drain tube?

JKTX21
11-12-2006, 02:41 PM
Thanks for all the input.

I noticed the oil was leaking from the very bottom (near the back) initially. It took about 3-3.5 quarts to get the oil back to full, after the boat sat for about two weeks leaking oil, so it was a slow leak. I cleaned the bilge out, filled it up with oil. I am 99% certain that it is the drain plug assembly on the bottom of the pan that is failing. There is plenty of clearance with the oil pan and the bolts on the bottom of the boat, so that is good.

It's very tight underneath there, any tips on replacing the drain hose assembly? Thanks

JKTX21
11-13-2006, 11:40 PM
Bump

Anyone had to replace the oil drain hose assembly on a 95-97 190? It didn't seem like there was enough clearance between the oil pan and bilge to back out the plug. I handed it off to my mechanic buddy and would like to give him some input if anyone else has had this problem (if he will have to lift the motor or not). Thanks.

JimN
11-14-2006, 12:40 AM
If there's not enough clearance to remove the plug, the motor and/or transmission will need to be raised. I would lean toward raising the rear of the motor because that's closer to the plug. Mark the fiberglass where the motor mounts are and loosen the top nut on the mounts. Disconnect the coupler and raise the rear of the motor with a 2x4 or something that won't mar the glass. Replace the hose and reassemble. Don't change the height of the motor.

JKTX21
11-16-2006, 12:46 PM
Got an update from the mechanic. He pulled the motor up a bit to replace the oil plug and discovered that the oil pan has a hole/leak in it from corrosion. It makes sense, the guy that owned it before me kept it in the water. So there was probably always water up to the bottom of the oil pan until the auto bilge came on.

The good news is that I will be getting a new HV pump while the motor is out.

TMCNo1
11-16-2006, 01:30 PM
Got an update from the mechanic. He pulled the motor up a bit to replace the oil plug and discovered that the oil pan has a hole/leak in it from corrosion. It makes sense, the guy that owned it before me kept it in the water. So there was probably always water up to the bottom of the oil pan until the auto bilge came on.

The good news is that I will be getting a new HV pump while the motor is out.


Glad to hear you found the problem before a lot of damage was done.

JKTX21
11-21-2006, 12:59 AM
An update on the boat with pictures. Don't take your plug out? Leave your boat sitting in the water all summer? This is what the oil pan from my boat looks like...

http://i16.photobucket.com/albums/b19/JKTX21/DSC01973.jpg

And the motor half way out
http://i16.photobucket.com/albums/b19/JKTX21/DSC01974.jpg