Oil leaking from cap?

[BiXLL]

Hi all, I have a 2003 Mercury 125 HP. I am docking this year at a boat club and have been storing with the motor tilted all the way to have lower unit out of the water. The other day I was walking down the dock and noticed a oil slick behind my boat. To make a long story short I figured out that the oil is leaking out from the oil tank cap. I checked it out closely and the O ring seems to be fine. The cap is marked to turn to right to close and to left to open. I am not sure why as I can pull the cap off when it is turned all the way to the right. I can see in the throat of the tank what looks to be sort of a thread, but I see nothing on the cap that would go into that thread.

Could I possibly have the wrong cap on this motor? The cap is yellow, with an O ring about half way up on its base and again I see nothing on the cap that would benefit me by loking it in place by turning it. Anybody have any ideas?

 

[carholme]

Re: Oil leaking from cap?

Here is the parts list for a 2003 125.

100/115/125 HP 80 JET (4 CYL) - Mercury, Mercruiser, Force, etc. Parts Lookup

See the cap as items 2 thru 5 under Oil Injection Components

There is a better picture in the service manual which I can send you if you PM me with an email address.

Gerry

 

[BiXLL]

Re: Oil leaking from cap?

PM sent. I still am not seeing anything on the cap that would lock into the thread portion of the throat of tank though? Should I be able to pull cap off when it is turned all the way to the right?