mercury plumbing Question

[Nitro 929]

I have a 1995 3.0 225 mercury and on the block below the starter twards the reed block is a check valve with a 3/8 stem. Whats supposed to attach to it ? Any help would be greatly appriciated. Thanks Scream & fly!

[shooter1]

It should be where the pressure line to the oil reservoir hooks up. It provides crankcase pressure to push the oil up to the tank on top of the motor.

Shooter1