lower unit gear lubricant

ljcatman

Petty Officer 3rd Class
Joined
Aug 27, 2008
Messages
91
how do you change the lower gear unit lubricant i don't know what to do. it's a 1972 mercury 9.8hp motor. can some one show me pictures of it being done. and is super tech gear lube good to use or a better brand then that. please help
were is the hole to change the gear lube at. and how much do i put in it
 

8075mercury

Petty Officer 2nd Class
Joined
Feb 13, 2008
Messages
113
Re: lower unit gear lubricant

Great little motors!!

Remove the small (slotted for a regular screw driver) screw on the side of the lower unit just above the anticavitation plate, and then remove the large screw near the bottom near the leading edge. Drain. Then, fill from the bottom hole until you get flow out of the small hole. Next, put in the small screw and then quickly put the large screw in while minimizing the lose of oil.

The drained oil should not be milky or have lots of metal particles. Some small amount of metal fines is normal. Milky indicates water intrusion and time for a rebuild.

You can get an owners manual from ebay or Mercury which shows this. Seloc is good too.

Good luck.
 

8075mercury

Petty Officer 2nd Class
Joined
Feb 13, 2008
Messages
113
Re: lower unit gear lubricant

Forgot the lube part, I like Mercury premium gear lube. I think you can get it at Walmart now!
 

Salacia

Petty Officer 2nd Class
Joined
Aug 15, 2008
Messages
132
Re: lower unit gear lubricant

I always put the oil back in with a merc pump i.e it screws into the bottom hole and then you pump it in. However recently found out that if you buy the gear lube in tubes you can just squeeze it in and it saves the expense. :)
 
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