Gear lube monitor question

[boatingedge]

I have a Merc 5.0L Alpha Gen 2. When changing the gear lube and topping off the gear lube monitor, I lost the rubber gasket that was in the monitor's cap. Is the purpose of this gasket just to keep the gear lube from spilling out of the reservoir or does it do something else. Does it matter if I replace it or not.
Thanks

 

[Bt Doctur]

Re: Gear lube monitor question

The caps vented anyway, guessing for spillage, guess you could use a large "O" ring.

 

[Don S]

Re: Gear lube monitor question

Get a new gasket. The cap has a rubber check valve, it will suck air in if needed, but will not let any oil out. The bottle will expand and bulge if too much heat is built up or water is getting into the drive along with the oil.
Without that, you would have oil everywhere.