: Lower Unit Leak

03-04-2011, 08:35 AM
I winterized my boat in October and stored it in my unheated garage. Yesterday I noticed a spot of oil about the size of a silver dollar under the lower unit. It does appear to be oil and not lower unit lube. The leak is right on the stainless bolt under the prop. It must have just started because I had not noticed anything til yesterday. I thought I had did everything right. Here is a pic if you can tell anything.

03-04-2011, 08:45 AM
Normally there is a rubber gasket on the screw, but sometimes they stick when you take it off. If that fell on the floor and you put the screw back in it will leak. I would check that first.

Gone Again
03-04-2011, 09:55 AM
Hard to tell from the picture. If you fogged the motor when winterizing and lubed the cylinders, it could be fogging oil coming out of the exhaust-which looks like the area that it is leaking from. This would be normal if that's the case. I would run it this Spring and watch it-see if the leak persists. I'll bet it won't!

03-04-2011, 10:58 AM
Its not from the screws to fill the lower unit lube. There is a big bolt above and below the prop and its leaking around the lower bolt. Not much at all. Did not fog motor as the dealer said fogging was not necessary on a 4 stroke. Just changed the oil, lower unit, treated the gas. I had checked periodically all winter around those screws for filling and draining the lower unit to make sure I did not have a leak. They are dry as dirt.

Robert M
03-04-2011, 09:50 PM
Are you sure it isnt exhaust/oil etc. running out by the prop onto the bolt. Cant tell much by the picture. It would be clear clean lower unit lube if you just changed it.

03-04-2011, 09:57 PM
Its leaking just behind that bolt wear it looks streaked. Very small amount. Can't figure out why it waited 4 months to leak. Boat has not been moved.

03-05-2011, 07:39 AM
Motor is a 4 stroke.

03-08-2011, 10:02 AM
Its definately motor oil. I think maybe when I changed the oil that the sponge around the drain hole was soaked with oil and it has trinkled down.