1986 yamaha 150 outboards lower gear lube and quantity

lime4x4

Well-Known Member
Joined
Mar 24, 2011
Messages
339
Reaction score
2
Points
16
Location
Palmerton, Pa
Time to change the lower gear lube in both of my 1986 yamaha 150 outboards. Can't remember how many quarts i need to do both outboards. Also was gonna use yamalube gear case lube 80w-90 anything better?
 

DennisG01

GreatGrady Captain
Joined
Sep 1, 2013
Messages
6,745
Reaction score
1,188
Points
113
Location
Allentown, PA & Friendship, ME
Model
Offshore
Without knowing exactly, it's probably roughly a quart. Get three quarts and you'll be covered. You can use the synthetic Merc stuff - it can deal with some water intrusion, just in case.
 

lime4x4

Well-Known Member
Joined
Mar 24, 2011
Messages
339
Reaction score
2
Points
16
Location
Palmerton, Pa
i was thinking a quart per drive but wasn't sure. Rather have extra then not enough
 

seasick

Well-Known Member
Joined
Aug 19, 2008
Messages
9,073
Reaction score
1,293
Points
113
Location
NYC
For my 150 the LU takes a bit more than a quart, something like 1.1 qts, an annoying value that forces you to buy 3 bottles of oil. I wouldn't use synthetic, the Yamalube is fine. Don't forget to get new gaskets for the oil plugs.
 

DennisG01

GreatGrady Captain
Joined
Sep 1, 2013
Messages
6,745
Reaction score
1,188
Points
113
Location
Allentown, PA & Friendship, ME
Model
Offshore
Some synthetics should NOT be used - or more specifically, any GL5 rated lube should not be used in certain lower units. The Merc synthetic is GL4 and is a fantastic gear lube. It's only a buck or two more per quart - it really is good stuff. I've been using this stuff in pretty much everything for a couple decades. Not that the regular Yamaha or even another manufacturer's regular stuff is bad - but the Merc stuff is a step up in that if you don get some water in there, it will still protect the gears. The regular stuff will not fair as well.
 

Doc Stressor

Well-Known Member
Joined
Nov 13, 2009
Messages
1,177
Reaction score
288
Points
83
Location
Homosassa, FL
Model
Seafarer
I'll second the recommendation for the Mercury High Performance (not their Premium) gear lube. I used that stuff in my old Honda BF90 and the original lower unit is still running fine after 21 years. That span includes a couple of leaky seals and few propeller shreddings. It's GL4 to protect soft metals and it seems to hold up well during water leaks until things can get repaired.