Yamaha Outboard Lower Unit Fluid Fill Question/Advice
#1
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Joined: Feb 2006
Posts: 40
Likes: 18
From: Boca Raton Florida
Hi all,
So I changed the lower unit fluid and silly me filled from the upper vent instead of from the bottom. It took the correct amount in total and I didn’t rush filling so I believe it’s correctly filled and presume since it fully filled with the correct amount and such that it doesn’t have an air pocket.
Looking for advice as I know it’s not a huge deal to do it again from the bottom but I’d prefer not to if I don’t have to.
So I changed the lower unit fluid and silly me filled from the upper vent instead of from the bottom. It took the correct amount in total and I didn’t rush filling so I believe it’s correctly filled and presume since it fully filled with the correct amount and such that it doesn’t have an air pocket.
Looking for advice as I know it’s not a huge deal to do it again from the bottom but I’d prefer not to if I don’t have to.
#3
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Joined: Nov 2004
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From: On A Dirt Floor
#5
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Joined: Oct 2010
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From: Cheboygan, MI
A little trick to save time and effort. keep the vent closed, open the bottom fill and quickly insert your fill tube, then open the vent. You don't need to drain the whole drive and you will only lose a few drops.
#9
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Joined: Feb 2006
Posts: 40
Likes: 18
From: Boca Raton Florida
Update I did it the simple way as suggested hooked up a fresh bottle of lube to the lower hole this time, opened the vent and pumped and yep had a small air bubble as it immediately spit out a bunch of air and some lube of course right onto me. Ran it last weekend and all good.
thanks everyone
thanks everyone








