Rotary Cutter Why is mower gear box oil milky?

[Hay Dude]

Could be from condensation if live in an area with temperature swings and humidity.

Amazing how condensation affects any partially full vessel.
Diesel fuel tanks included.

 

[repete]

Amazing how condensation affects any partially full vessel.
Diesel fuel tanks included.

In the winter especially in W Washington I keep my fuel tanks full. Fuel is underground and run through a Goldenrod water block filter.
I also drilled and tapped a plug in where my breather cap went in with a 1/4" barb fitting. I then ran a 1/4" rubber fuel line over to a mower support piece and ended with a 1/4" fuel filter that allows breathing in both directions to keep dust and whatever out. I know... Overkill...

 

[kioti28527]

7’ Frontier mower. I ran the mower for first time in 2 -3 months, THEN I decided to check the gearbox oil level (I know). Oil level was fine, but oil looks milky. How did water get in? Or has it always been there?

5 years ago, I changed the input shaft seal because, vent/filler bolt was plugged, and unvented it pushed oil out the input shaft seal (on hot days).
I’m pretty sure I drained most, if not all, of the oil out at that time with a suction hose, and refilled with new oil.

When I checked oil BEFORE the last time using it and before turning it on, oil level was fine and oil was clear. I’ve noticed no oil leaks outside of gearbox. Vent is working fine. I store mower outside but cover the gear box with a plastic John Deere garden cart.

Would oil get water just from the gearbox “breathing” through the vent over a period of months? Years? Could water be in gear box for years, but I don’t notice it at the beginning of the year when it’s not stirred up? And my dipstick only touches the top layers? I’m mystified.

Condensation?it doesnt take alot to get milky,especially running it till its hot and shutting it down in colder weather

 

[CobyRupert]

I have a piece of equipment with a similar breather. Checking oil before using was fine. I store the equipment outside. On advice from someone here I use teflon tape to wrap the breather when the equipment is not in use and this has stopped the issue of getting water in the oil. Only thing I can think of is that a combination of rain and wind was driving the water into the gear box.

The previous problem I had with plugging the breather (actually mud, grime, or wasp plugged it) was oil was getting pushed out the input shaft seal when the gear box would get warmed in the sun. The gear box needs to breathe.

I’m just surprised that I’ve had mower for many years, and only this year, 2 months after not having milky oil, it went milky. It’s been a dry summer, and gearbox is keep under a cover.

That’s why I wonder if oil always has water in it, but I just don’t see it at the beginning of the year if I haven’t mixed it up yet?

 

[big bubba]

OP: since your ambient conditions promote condensation, keep in mind the same could occur in your hyd sump as well.