When I filled my drives w/oil I just filled them to the plug on the side of the drive at the top. Is that enough or do they need to be filled to the mark on the dipsticks ?

fill from bttm to top plug. insert top and bttm plug and fill to mark on stick from dip stick tube .

I do mine just like 28SS said only when the oil gets to the top plug I put the plug in and pump until resivoir inside transom reads correct on it's dipstick.....Fred

Fred has it right

Thanks David....maybe it was you that told me to do it that way,....anyhow it has worked great doing it that way.....Fred

I can only fill mine till it just starts to touch the dip sticks. If I go any higher it comes out the vent hole when I start running it hard. I use the HP merc oil maybe I should try something else.

Mine does the same thing as Dougs. I fill until it just shows on the dipstick ...any more it will puke out the vent when running hard The Ironman.

Ironman are you running a 3 or 4 blade prop. I am running a 4 blade Hydromotive 25p and I wander if it is makeing the drive work harder and is foming the oil and we should switch. Doug

It does the same thing with 3 or 4 blade props cleaver or round ear. I do not think that the prop has any effect on oil level. it may effect oil temp but I have not measured that yet. Ironman.