Yamaha Outboard Lower Unit Fluid Fill Question/Advice
 

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.

Why not drain the oil and catch it in a clean container for re-use and put it back in correctly? Then you don't have to wonder the next time you drop the hammer.

Winner winner chicken dinner

Thanks, you’re right keep it easy and worry free redo it and reuse it.
Thanks for the advice

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.

That’s the way
 

Just fill it from the bottom and see if anything seeps out at the top.

No need to drain.

Id run it........it will purge any air out then top it off if need be from the upper plug

I appreciate all the advice everyone.

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:)