35Hp removing lower unit vent screw

[skytracker]

I serviced the lower unit on my 1987 35Hp Merc last fall. Now I wanted to top it off and make sure there weren't any air pockets and the vent screw will not come loose. I've tried PBblaster and light hammering with a mallet, no go.
Any suggestions appreciated...

 

[Yepblaze]

Re: 35Hp removing lower unit vent screw

Let me begin with saying that the lower unit is filled from the bottom, either by squeezing the oil out through the pointy end of the bottle or pump device screwed into the drain hole.

If you want to check the oil, most of us would just asoon drain and refill rather than try to top off by way of vent hole.

For just a few bucks (maybe $3.99-20) you should be able to buy a impact screwdriver with bits. Place the best fitting screwdriver tip on it. Twist it to the left slightly and hit it with a hammer.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=37530

 

[skytracker]

Re: 35Hp removing lower unit vent screw

Thanks for the reply. I fill from the bottom also, but i usually crack open the vent and pump in fresh lube until it comes out the vent. What concerned me was how it froze up since last fall.

I'll try the impact screwdriver and see how it goes.