Hi experts,
I have a 2000 Merc OB 90HP ELPT Serial on the sticker says 0T067768. Recently purchased the boat (pontoon) and motor from a marine shop (consignment) and have taken it out a few times. This last two times I trimmed down in the parking lot, I noticed motor oil drip from the prop collar (see pic...the dark streak on the skeg is the oil). It wasnt a lot...maybe 1oz. I cant find a whole lot of good info on this issue except for two-strokes...and when I asked a marine mechanic he couldnt think of how motor oil would drain down there from a 4-stroke. The inside cowl bowl and outside of the motor looks perfectly clean. No oil or residue, no leak from the fill cap or dipstick.
Oh and the motor runs great. There is no milky oil, in either the motor or the lower unit. And I get almost all 6000 RPM at WOT. Compression check looks good, too.
So, I'm kinda baffled at how I would get oil down there, too. Is there an oil cooler on these motors that may be leaking? I am trying to look at microfiche on my motor but several of the sites dont recognize the serial #. I included a pic of that, too, if anyone knows which motor it is.
Any guidance or suggestion are appreciated.
I have a 2000 Merc OB 90HP ELPT Serial on the sticker says 0T067768. Recently purchased the boat (pontoon) and motor from a marine shop (consignment) and have taken it out a few times. This last two times I trimmed down in the parking lot, I noticed motor oil drip from the prop collar (see pic...the dark streak on the skeg is the oil). It wasnt a lot...maybe 1oz. I cant find a whole lot of good info on this issue except for two-strokes...and when I asked a marine mechanic he couldnt think of how motor oil would drain down there from a 4-stroke. The inside cowl bowl and outside of the motor looks perfectly clean. No oil or residue, no leak from the fill cap or dipstick.
Oh and the motor runs great. There is no milky oil, in either the motor or the lower unit. And I get almost all 6000 RPM at WOT. Compression check looks good, too.
So, I'm kinda baffled at how I would get oil down there, too. Is there an oil cooler on these motors that may be leaking? I am trying to look at microfiche on my motor but several of the sites dont recognize the serial #. I included a pic of that, too, if anyone knows which motor it is.
Any guidance or suggestion are appreciated.
The L/U or gearcase lube is SAE 90 from Merc. I just changed that last week and it is blueish green. The motor oil is 25W-40 and is standard engine oil color. That 25w-40 is what appears to be leaking. When I swipe it off of the skeg with my finger or a towel it is the color of motor oil, and not blue/green in any way.