I'm new to these tractors recently, but had a need to locate the filter/screen today, too. The filter/screen cover is located directly underneath the left footrest behind the heel position, directly in front of the axle housing. It's diamond shaped, about two inches long, with two bolts holding it in place. Remove the bolts and the filter assembly comes out. BUT, first you must remove the brake rod, as it is in the way of pulling the filter all the way out. Remove the cotter pin, then the pin, and drop the brake rod downward. The filter/screen will now pull all the way out. If you haven't found the drain plug under the bottom of the differential and already drained out the lube, the lube will surge out once you pull the filter/screen out. I didn't locate the drain plug, so most came out the filter/screen hole for me.
Incidentally, I purchased my tractor exactly one week ago. It was a cold day, not much above zero F, so I didn't take a great deal of time testing all functions on the tractor, and loaded it quickly onto my trailer, then drove home 175 miles. Had I taken the time to do so, I would have discovered the 3 point lift arms were not lifting. Might have gotten a break in the price if I'd found it before paying for the tractor?? Live and learn I guess.
Anyway, this morning, a week after bringing it home, temperature is 9 F, went out to the unheated shed and started it up just fine. Let it run for about 5 minutes, then decided to try the rear lift..........nothing moved. Immovable as can be. In fact, when I moved the lever to "down", the levers actually lifted about an inch or two, then quit altogether. Go figure.
Here is what I found in the process of draining it out: As the differential lube also serves as the hydraulic fluid, I figured it was probably just stiff, but decided to open up the breather plug just under the front edge of the seat to see what might come out, if anything. Loosened it up and foamy, super thick lube started to push out, like under pressure somewhat. Uh-oh....so quickly concluded that maybe the filter/screen was caked over with this gucky stuff. After finally locating it (as described above), I removed the two bolts, dropped the brake rod, and slowly pulled the filter screen out. Once it was totally removed, the gear lube began to slooowly ooze out. It was as thick as taffy and the same color as tan taffy, too. What also became evident were the small ice chunks which were present in every glob of it. So, I figure there must have been water in the lube, then it froze up. There was absolutely no way that even one drop of this stuff was going to pass through the filter screen, thus choking off the flow of oil back to the return pipe that take lube back to the hydraulic pump near the front of the engine. So, took the screen back into a heated location and totally cleaned it up, including a total bath in sudsy hot water until all gunk was out of it.
Tonight, the tractor gear case is still slowly draining out one small blob at a time. Temps are supposed to moderate this week, in a few days up to the high 30s. When it does, I'm planning to fill to capacity the transaxle/hydraulic sump with 10W30 motor oil and run it that way until later this spring when temps rise up into the 70s, then will drain it out again and fill it with synthetic 80 weight gear lube. That is, provided the hydraulics work as they should and that nothing else in the hydraulic system is defective. The detergent motor oil might help to clean out the transaxle housing, too.
My Beaver has a couple of other minor issues, like a temp light that is ALWAYS on, ice cold or hot. Never shuts off until ignition switch is shut off. Must be a gremlin in the system somewhere.......I'll get him later. Oh yeah, the seat is busted too. Gotta get suggestions for a replacement, as it's not what you'd call a comfy ride. Otherwise, no complaints. I think I'm gonna like this tractor.
Best of luck with yours.
Vvm
