Possible lower unit leak

[trobinson017]

Hey all,

This may sound like an obvious, no-brainer diagnosis but I want to check anyway. My boat, with a Johnson 130 Ocean Pro outboard, sits on a lift off of my dock. This morning when I lowered the boat into the water, as soon as the anti-ventilation plate on the motor went underwater an oily slick appeared, streaming slowly away from the lower unit. I left the boat in this position for a few minutes and the slick grew pretty large, about 3 ft. in diameter around the entire lower unit that was in the water. I did not start the motor.

I'm guessing that a gasket is blown where the lower unit bolts onto the rest of the motor. Is that a correct assumption?

I've been planning on servicing the water pump soon so if it is a gasket I suppose now is the time to take care of both issues. So, do I just need to buy a gasket or are there other things I should replace and/or check?

TIA!

 

[petryshyn]

Re: Possible lower unit leak

Lower unit is easily checked by monitoring your lower unit lube level and color.
You may have simply observed a fuel slick from unburned fuel in the exhaust or fuel expelled from the silencer, especially if the motor was tilted all the way up or tank vent was closed when last stored.

 

[another todd]

Re: Possible lower unit leak

Check the lower unit oil to see if it is milky, a sure indication of a lower unit leak. There are seals and a gasket under the water pump, and that would be a good time to change them if they are leaking. When you remove the lower unit to change the WP, have the lower unit vacuum and pressure tested to see if you actually have a problem. I may just be left over oil in the exhaust you are seeing and not a problem at all.

 

[trobinson017]

Re: Possible lower unit leak

Update: I drained the lower unit oil and sure enuff it was milky. I could actually see a clearer watery liquid come out just as I removed the top bolt. I've completely drained it. So, what should I do now? Plan to remove the lower unit completely to have it checked and rebuild the WP at the same time? I don't have a trailer and the boat sits on a lift over the canal. My only options are to borrow a trailer and tow it to my driveway, drive it to a marine mechanic place or have a mechanic come service it at my house. Do you think I would be able to refill it with fresh oil just to be able to drive it to a marine mechanic or boat ramp? Or should I have it towed to a service place or boat ramp? I'm guessing refilling and driving to a ramp or facility would be unwise simply for the fact that I'd be polluting the water in doing so. I dunno. This is my first boat and I've never dealt with this kind of problem before.

Any and all advice greatly appreciated!

 

[trobinson017]

UPDATED: lower unit leak

UPDATED: lower unit leak

See message immediately above for update on my leaky lower unit.