lower unit oil

[Mass101899]

Am new to boating. I have a 1980-81 80HP Mercury outboard. I winterized it in the fall to include draining and refilling the lower unit. I was surprised as to how little it took before it appeared full. I did fill from the bottom with a pump type dispenser and the lube did exit the top hole. Does anyone know approximately how much oil this lower unit holds? I do not want to guage on how much drained out since this is the first time I serviced it and do not know if it was filled to maximum. Thank you... am learning a lot here!

 

[schaiss]

Re: lower unit oil

When you originally filled the LU, as long as the engine was trimmed completely down and you added lube until it seeped out of the vent plug on the top of the LU, you do have it filled with the correct amount. If you want to know the exact amount of lube, the easiest way to determine the exact amount of gear lube would be to completely drain the LU into a 24 or 48 ounce measuring cup (can get one at K-Mart or WalMart). If this lube is still good it can then be teransferred into a tube and pumped back into your LU. Your LU should not require any MORE than 20 ounces.

 

[andrewkafp]

Re: lower unit oil

As Aqua said.. Let it drain all night and then refill till all the bubbles are gone. Try not to let air get in as it reduces the volume.If you want to know the exact amount, it will be in the manual, but my 1980 50HP only takes about 600ml.<br />You can wait a day and squeeze a bit more in if you think there is air in there.<br />BTW Watch out for those little counter sunk gaskets on the fill/drain screws. They can easily roll away and vanish. I put nice bright blue ones on so I can see them...