Gear lube vanishing

[8mk]

DP-SM outdrive missing a quart of lube but no water in lube that I removed and there is vacuum on the dipstick when I remove to check the lube I can hear air in rushing so how can there be a leak?
thx
Mark

 

[bruceb58]

Re: Gear lube vanishing

Have you looked in the bellows yet?

You need to pull the drive, drain the lube and do a pressure test.

 

[8mk]

Re: Gear lube vanishing

looked in the bellows and all is clean as I was just reolacing the u joints.What is the vacuum or pressure I always get when I unscrew the dip stick rod.It would seem to me if there is a release of some pressure or vacuum that it would be leak free but I will try to rig up a pressure test.

 

[jerryjerry05]

Re: Gear lube vanishing

A whole Quart??
When the exhaust goes through the drive it heats it up and the heat causes pressure.
The pressure pushes the oil out.
There are 2 seals in a back to back configuration.
One's designed to keep the water out and the other's designed to keep the oil in.
Possible one went bad?
Pressure test it.