Thats just a fill vent plug, there has to be a reservoir some where to keep the lube level full, the lube lever needs to be above that plug for the upper gear set and clutch

I see white lube bottles under the starboard gunnel...........??.or are they trim pumps

what year is this boat? early bravos did not have an inside reservoir. the transom assy. have had the upper pin redone so assuming not real new and the sticker is most likely not the original which is why no numbers.

I think you are seeing blowers...BUT I will look again. Thanks

1988 Formula 311 SR-1
Please explain: "...the transom assy. have had the upper pin redone so assuming not real new"
My previous F311 (same year and model) had "stamped" drive # on the back plate. I know these drives had been "gone through"...I was just looking for serial # info so I could know/understand the vintage of the original drives.
Thanks

I dont think the 88 bravo had internal reservoir. you pull the top plug and fill it to that level from the bottom. the plate on the top of the transom assembly is not stock. that is because the back was cut open to gain access to the upper pin. if the drives were redone then those are most likely new stickers. if you are willing to peel the sticker off then sometimes the numbers can still be seen in the surface of the drive.

not really, the passage for the reservoir is at that same level so that is all they fill to in the drive, air is trapped above that. the reservoir is to allow the oil to expand and contract with temp and to let you know for sure you have oil. the early ones if they leak you only find out when it locks up.

ya , blowers

Thats how it was on a buddies old Baja. Drain/fill plug behind the props and then pump the oil till it weeps out of the top plug. Ill do some searching to see what I can find out for you.

Here Ya Go.

https://www.sterndrives.com/changeyo...ogearlube.html

If the gear lube reservoir is higher than the top of the drive, which it should be, the lube will fill the drive to just below the top cap.