The transmission goes dry & the hydraulic reservoir gets over filled. There is no connection between the trans cooler & hydraulic cooler. Recently the tractor will only go fwd & locks up when the reverser is in the reverse position.
Welcome to HEF Bill . When you say the transmission goes dry I assume you mean the reverser ? The mfwd clutch in the transaxle is activated by hydraulic oil (transaxle oil). The park brake and diff lock are both operated by mechanical linkages. I suspect there a reverser cooler line and a hydraulic cooler line that are crossed.
I will check the lines, although it has taken several weeks to move all the oil from the transmission to the hydraulic sys. It seems to be happening at a faster rate & yesterday it suddenly "locked up". Your comment about the park brake & diff lock seem to come into play.
Has any cooler lines started leaking or blown off connections where they are clamped on lately?
no, nothing has changed in the past 9 months, except I changed the filters, removed the engine oil pan, cleaned it (the pan was glued to the block & the drain plug was welded) & used J.D. specified oil & coolant. Replaced all the o-rings on the hoe control valve & new hoses on the steering cylinder. The oil loss problem started last Spring (2023), but now it's about every 6 days. There was some comments about problems with aluminum oil coolers. Mine is steel. The repair manual talks about the different oil being mixed in the hydraulic filter which contains a relief valve. I wonder if there could be a possible leak across the valve ?
Just to clarify what machine you have , what is the full machine serial number ?
TO410CG727250 now another problem has developed due to low oil. I moved the machine fwd about 20 feet, then tried to go in reverse. It was like it was in "park". Checked the oil & none on the dip stick (just put oil in trans a few days earlier). Filled the transmission full. Now it only goes fwd. when the engine runs, even with the reverser lever in neutral & then there is a squealing noise. when in reverse the machine won't move (clutches locked ?). The transmission can not be shifted into any gear with the engine running, with the clutch down & the reverser lever in neutral. I don't see any oil leaks, except for the hydraulic cylinders on the back hoe. The engine oil seems to be creeping up. (last 2 times, to fill the transmission I pump oil from the hydraulic reservoir, then top off the hydraulic reservoir with new oil.)
I assume you are referring to Operation and test manual TM1468 ? As per the information I have ,the reverser filter and the hydraulic filter are completely separate systems with no cross connection possible at the filters. Take a screenshot or picture of your manual information if you can. . To help determine if the issue above is in the reverser or in the transmission, I would remove the driveshaft between the reverser and the transmission and see if the reverser output shaft turns freely when in forward or reverse with no squealing. . The engine oil creeping up would have to be either engine coolant and or diesel fuel leaking
yes, I see now that the reverser is a seperate system. The last time the tractor moved properly, it was going forward. when the reverser was moved to "back-up" it wouldn't move. Now, it makes no diff. which position the reverser is in, it only goes forward. while the engine is running, the transmission can not be shifted in or out of gear. I think the manual read somewhere that the clutch is operated hydraulically. So, if the filter is plugged the reverser does not function. I removed the filter. I think I replaced that filter last January. Anyway the oil looks too dirty. I will get the front wheels up about a foot & take the plate off the bottom of the reverser/clutches, check for broken parts & sludge. Now I see that it's the reverser dip stick that shows oil 1/2 way up the stick & the "trans" stick shows it needs oil. Also remember that when I changed the hydraulic filter that the canister was dry (very little oil in it). So oil is not being transferred from one system to the other, something else is wrong. Op & test TM-1468 (Oct 88) Tech Manual TM-1469 (Dec 88) The output shaft does turn freely when the eng is not running. Not inclined to get under the machine with engine running. With the trans in neutral, i pull the machine backwards with the hoe. put the trans in first or second, start the engine, reverser lever in fwd or neutral & go forward, no problem.
I agree , sounds like the reverser forward clutch is locked up (clutch plates severely warped or welded together). The reverser oil must smell burnt ? Post what you find after the reverser inspection. .
oil smells good, lots of chips cover the bottom plate. they appear to be some kind of fiber but like chips of rust. removed the pump screen, it's clean. Don't understand where all the oil went when it was filled about a week ago. Maybe the pump failed because there was no oil on the dip stick. looks like the floor/seat in the cab has to be removed to gain access to the unit. Looks like the only option is to replace what is damaged.
Remove the large rubber plug underneath where the bell housing bolts up to the engine and check for any significant amount of oil. The bell housing should be dry. The repair manual TM1469 will give the reverser removal procedure.
that "large rubber plug" is long gone & there is no signs of oil in the bell housing. I think there is a little on the output shaft of the transfer case. I'm thinking that the relief valve has failed or the filter is completely plugged. The output shaft turns like it's new. Where do all those flakes come from ? Got a quote for a rebuild; $4000 +shipping, which I don't have at this time. Maybe just get the rebuild kit for $1100. While I'm about it, might as well determine why the foot lever is disengaged & I can't get out of 4-wheel drive.
If you are mechanically inclined or have mechanical friends that work cheap the reverser repair option would be ideal. The critical parts to pay close attention to would be the reverser oil pump, individual clutch discs and plates ,bearings and of course replacing all seals and gaskets. Sounds like you still need to determine the cause of the reverser oil loss. . The MFWD (4 wheel drive) clutch is spring applied and hydraulically release so the system defaults to MFWD being engaged. The oil supplied to the MFWD valve on the floor comes from the main hydraulic system priority valve. IIRC the drum item #8 in the screenshot below was the weakest link. The fingers on the drum would break off and the clutch piston would jam out of position and leak. A pressure test would be in order to troubleshoot the potential problems correctly. https://partscatalog.deere.com/jdrc/sidebyside/equipment/59730/referrer/navigation/pgId/4138 . .