Montana 3840: hydraulic system idiot light

[ramonajim]

Greetings all - looking for some guidance on my little ghetto tractor.

Montane 3840, previous owners seriously abused & neglected it from new to ~ 1600 hours. Left it where it "stalled out" until 3 years later I offered $1000 for it and its FEL (with a busted arm). I'd just closed on my first farm, and I figured if the Montana got me through the first 6 months of farm start up (it was a foreclosure, empty for 2+ years) it would be $1000 well invested.

Got it started, brought it home, and did catch up on the basic maintenance. Got the FEL arm welded up, and have been happily using it for the past nearly 3 years.

To my question: dash panel includes what the (hilariously translated from Korean) owner's manual calls a Hydraulic Filter warning light. Troubleshooting part of the manual says filter needs replacing if that light is on.

Light started coming on at seemingly random times - usually when mowing (3 pt deck, not hydraulic). If I'd raise and lower the FEL a few times, light would go out. Over about a month, it started coming on more often and staying on longer. Hydraulics seem to operate normally whether light is on or not.

Gave the tractor a spa day. - all fluids and filters replaced, zerks lubed, etc. No change to the idiot light's tendency to come on, never while using hydraulics (other than steering) and usually after I'm 30-45 minutes into whatever I'm doing.

Assuming it's not actually a new, plugged filter - any idea what might be going on?

 

[rScotty]

Does it have a cleanable sump filter? Most of the shuttle & power shift tractors from that era have a cleanable filter in the transmission/hydraulic sump as well as a replaceable spin-on filter.
Check if yours does. If so it is likely in the line that goes from the lower side of the transmission housing up to the spin-on filter. The cleanable is sometimes under an access plate in the side of the transmission housing - but I've no idea where Montana put it or if they even have one. But you asked for ideas, and that is a good place to start.

My guess is you need to take that filter out and scrape the sludge off of it. They are typically a 200 mesh stainless screen and pick up a lot of metal sludge as well as the goo that happens when water gets into transhydualic fluid.

Drain your hydraulic fluid first. If it is new enough fluid to reuse, let it set absolutely quiet for a few days or longer and then - very carefully - decant or better yet siphon it off to leave the sludge behind and you can usually re-use 90% of the old fluid if not too old.

You can ignore that cleanable filter for awhile, but eventually it will starve the hydraulic pump and when that happens cavitation will kill the pump pretty quickly.

First symptom of a clogged cleanable filter is often that either or both the FEL/3pt and/or hydraulic shuttle shift seem to be taking too long to engage. They are starving for fluid.
rScotty

 

[CoyPatton]

I agree with rScotty. I would look for the screen in the hydraulic sump. It will be very low in the sump, so do yourself a huge favor and drain the hydraulic fluid 1st!
YOU WILL DRAIN IT ONE WAY OR ANOTHER!
Clean the screen. I have used a bit of diesel in a pan and a soft brush.
As for location, follow your suction line to the reservoir and then opposite the suction line look for a removable plate on the housing.