In article ,
GeoLane at PTD dot NET GeoLane at PTD dot NET wrote:

The machine now has 265 hours on it and is beginning its 6th season.
The hydraulic oil has gone from clear to light tan and does not smell
burnt. I can see some milky white oil droplets reminiscent of an
oil-water mix clinging to the inner wall of the dispstick tube.

Two clues: "light tan" (as in suspended rust particles, probably) and
you see condensation on the dipstick tube. Be penny-wise and
pound-foolish if you like, or accept that when you bought far more mower
than you needed, you bought the maintenance expenses that go with that.
Hydraulic fluid should look very close to the way it looks coming out of
the bottle at all times, or there are going to be (or already are)
problems.

53 hours a year. Poor thing probably never gets adequately warm to boil
out condensation, so your "light use" is actually harder on it than
proper commercial use, where it would run all day and heat the hydraulic
fluid up. You should start hiring out to mow other lawns.

Before you put it up next year, mow for as long as possible to heat it
up and dry it out as much as possible.

If there is a vent on the hydraulic system, you might tie a bag of
desiccant over that vent when the mower is stored. If there are any
filters (fluid and/or vent), change those out, too. Likewise the engine
oil.

If you can't find the vent, bag the whole mower up with dessicant.

--
Cats, coffee, chocolate...vices to live by