gearcase lube is black

[bergsofafeather]

This is my first time changing the lube in my lower unit, 85hp, 1975 Mercury. Bought a pump and on the back it says "examine for metal filings, milky appearance, or black color with burnt odor. If old lube has any of those characteristics, see your dealer." I've got black, with a little odor. I had it changed two years ago before salmon season, ran the boat a dozen times during the season, and it has sat idle ever since. I bought new Mercury High Performance Gear Lube +, and it is green right out of the bottle. Tell me this could be normal?? Also, the salesman told me it would take a quart, maybe a little more, I only got half a quart out. Oh, I almost forgot, just today I got done running 1 bottle of Sea Foam Deep Creep through the carbs, and put regular Sea Foam in my tank, if that would have anything to do with it.....

 

[paulgp6022]

Re: gearcase lube is black

The seafoam through your carbs doesn't have anything to do with it. The black is usually a sign of burnt up lube. Either it was never changed or it was never filled up all the way and ran hot. The new lube is greenish-blue out of the bottle (good stuff)! Fill it through the drain hole until it comes out of your top vent screw hole, then install the vent screw before removing the fill container. Then quickly fit the lower plug into the bottom. My 75HP holds 22 ounces, so yours should take more than a half quart. If only a half quart came out, and there wasn't a milky color to it, then I think it was never filled up all the way, and ran hot. If you had a bad seal, it would have let water in and turned it milky in color. Just be sure to fill it all the way up this time! Good luck.

 

[bergsofafeather]

Re: gearcase lube is black

SS- It took a little over 20 oz. so I feel better about it now. Thanks for the reply.

 

[paulgp6022]

Re: gearcase lube is black

There you go, she was just thirsty! Good luck