1984 150HP lower unit oil (middle phillips head screw)

[BJBUSYBOY]

There are 3 screws in the lower unit. I filled it up with oil until it came out of the middle screw (phillips head screw). What is the top screw for? I've read forums that said the middle screw is a "shifting fork screw" and should not be removed. We'll.....it WAS remove and filled to that level. Took it to the lake, everything shifted fine and ran fine. What happens if this screw is removed and filled to that level?

 

[ezeke]

Re: 1984 150HP lower unit oil (middle phillips head screw)

The two matching screws are the ones to remove. By filling only to the phillips screw, you are not getting enough oil into the gearcase (besides risking getting parts out of position when you remove the phillips screw).

Force oil into the lower fill opening until it runs out of the upper vent opening and you will have the correct amount of oil.

 

[Vic.S]

Re: 1984 150HP lower unit oil (middle phillips head screw)

You have been lucky!

SEE THIS DIAGRAM

Dont undo the philips screw #3, it holds the pinion bearing in position I think.

The drain/ filler screw is #47 and the level screw is #41.

Top it up to the correct level, #41, and dont undo the Philips screw again. You might not be so lucky next time.

On some there is a Philips head screw that supports the shifting mechanism inside the gear case