Logo
FULL SITE MENU

Lower unit oil leak on a 99 hp after laying on itbs side

F

followingsea

Regular Contributor
"I just bought an older (8

"I just bought an older (88?) 9.9 Yami 4 stroke yesterday. I had it laying on it's side on the trip home --at least a few hours. In the process of unloading it and hauling it inside it trailed about 1/3 cup of oil. Looks like most of it came from the little hole near the lower unit oil fill hole.
Is this a major problem or just happens when it's layed on it's side the wrong way? I'm including a photo of where it was leaking.
116911.jpg
"
 
"Dennis, I am not an expert bu

"Dennis, I am not an expert but I had the same problem at the end of the season. I was told that it's "unburned gas/ oil that comes out the casting holes" That made sense to me as I had just winterized the motor.Sprayed fogging, ran stabile etc.. and raised the motor up for the trip home. I doubt it's anything major, but the tech guys will tell you for sure. dave"
 
"Dennis, this being a four str

"Dennis, this being a four stroke, it does have internal oil. If what leaked out appears to be "motor" oil there is a chance that you drained it by laying it on the "wrong side".

Four strokes can be layed down but usually only in 2 of the 4 possible ways you could put a motor on it's side. Some of the newer ones even have a sticker on them telling you which side to lay it on.

With it in it's upright position, check the oil level - you are probably going to need to top it up, or better yet, change it completely.

Here is recommendation for storing a 4 stroke Merc - your motor should be similiar...

116914.jpg
"
 
"Thanks for the help David and

"Thanks for the help David and Graham. I'm almost certain I laid it over the wrong way. The learning never stops!

In the process of hauling it home and then picking it up and turning it I had the powerhead nestled in my belly and the leg sticking out (sitting basically horizontally) while I moved it. Must had tilted it the wrong way and got motor oil down the wrong place.

I checked the oil level this afternoon, after I had it standing up for a while. The oil was clean and about halfway up on the oil level range of the dipstick.

Just curious:

1) WHERE exactly does the oil get out when the motor is tilted the wrong way? Is there a breather of some sort that it comes out?

2) That little hole that it was oozing out? Inside the case, is that just a tube the runs from the bottom interior of the cowling area and downward for draining off excess water, gas or oil that might accumulate up top?"
 
"Dennis, when the motor is lay

"Dennis, when the motor is layed down "wrong" (for lack of a better term), the oil seeps from the sump into the cylinders then makes it's way out of the exhaust (which is down the leg and ultimately out the propeller).

That little hole that you found weeping is most likely a drain hole to allow water to exit to prevent a freeze crack - the oil running down the exhaust housing simply made it's way out of there as well..."
 
"Graham,
Thanks the continuin

"Graham,
Thanks the continuing education. What you said fits because there was also some oil leaking out by the exhaust (behind the prop).
I guess it's no different than turning my car or P.U. upside down for a few hours.
happy.gif


This little 4-stroke is new learning experience."
 
"Dennis, if you haven't st

"Dennis, if you haven't started it yet since it leaked the oil, you might find it a little difficult at first.

Best to clean up the plugs (or replace them if they are due) - because basically you have flooded your engine with motor oil - which makes it quite tough to start - and expect a good bit of blue smoke out of the exhaust until you get it burned off.

Otherwise, you haven't hurt anything...."
 
"Thanks again Graham. I'll

"Thanks again Graham. I'll let it sit in the upright position for a few more days then pull the plugs for a good look. I'll replace them if they need it. Also, several pulls without the plugs ought to help air it out a little."
 
I have a 98 9.9 mariner engine

I have a 98 9.9 mariner engine and notice oil leaking at the prop after doing a eng. run. Whats the problem ????
 
"Stephen, that is totally norm

"Stephen, that is totally normal if the motor is a 2 stroke. The motor is grossly inefficent - most of your gas and oil goes right out the exhaust without being burnt, additionally, all the residue from what does get burnt goes down the exhaust along with the cooling water.

Particularly after a long run, when you haul the boat out, all that "goop" slowly makes it's way down the exhaust housing and out through the prop resembling an oil leak....."
 
Back
Top