Lower Unit

[gwh2224]

I just changed the oil in the lower unit of my 1992 115 Yamaha. I didn't notice anything unusual...The old gear oil looked fine. I did notice a very black greasey substance that had leaked out from just below the prop. Also, I noticed a small amount of the same black grease inside the prop. Any idea what this might be?
Thanks for your help.

[Ken]

gwh,
Not to worry - that "black grease" is just residue from the exhaust - burned oil. Most of the exhaust goes thru the center of the prop.
When you change your oil (once a year), you need to also pull the prop and inspect for fishing line wrapped around the prop shaft that could cut into the shaft seal.
Also, need to re-grease the prop shaft splines and prop splines with marine grease to prevent corrosion between the two. I like to put a little grease on the thrust washer also. Be sure and use a new cotter pin on the prop nut.
Good luck [img]smile.gif[/img] ,
Ken K

[gwh2224]

Thanks Ken...Another question...When I removed the bottom drain plug of the lower unit, I noticed a few, very small metal shavings attached to the plug. Is this normal wear, or does that indicate a lubrication problem. I really appreciate the help.

[Ken]

gwh,
A few small metal shavings is normal. Just make sure you use a quality 90W gear oil designated for lower unit use - Yamaha, Pennzoil, Lubrimatic.
Ken K [img]smile.gif[/img]