M Series Hydraulic Filters

Fruitfarmer131

New member

Equipment
M6040, M8540, M5950, M7040
Nov 1, 2013
8
0
0
Kewadin, Mi 49648
Developed a hydraulic leak in a M6040, and couldn't locate where it was coming from other than the right side of the tractor, behind the fender. I drained the fluid, pulled both filters, only the front has a magnet, by the way, and disconnected and inspected two lines from the control, and the metal line that goes from the junction block back to the remote valve control. They all looked fine, so reconnected everything added some fluid back in and tested, still difficult to determine location of leak, but I'm beginning to believe it may be that one of the filter is leaking. My question is are both these filters, sump filters, in other words are both just filtering fluid drawn from the transmission case, or is one an output and under pressure?

In any case I'll run down and pick up some new filters, drain, replace and refill and check.
 

North Idaho Wolfman

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Lifetime Member

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
31,024
6,994
113
Sandpoint, ID
You won't have a pressure leak at the suction filters, look at the smaller pressure lines for the leak.
 

Fruitfarmer131

New member

Equipment
M6040, M8540, M5950, M7040
Nov 1, 2013
8
0
0
Kewadin, Mi 49648
Both filters are in the suction line in parallel.
There is a service manual available here
http://www.kubota.cz/data/soubor/WSM_M6040_7040 EN.pdf
Finally got in contact with service at dealership, they didn't know offhand, so thanks. That service manual will come in handy, thanks very much.

I did find the leak after removing the rear tire, steel pressure line from pump, had developed a crack. I removed and welded it back up, seems to be holding.
 

100 td

Active member

Equipment
B21TLB (B21, TL421 & BT751) Toyota SDK4 T116 Bobcat
Aug 29, 2015
1,776
9
38
ɹǝpunuʍop
Where was the crack? Any pics? Just wondering the how and why, pressure on the pipe, vibration etc. something hit/push it?
 

Fruitfarmer131

New member

Equipment
M6040, M8540, M5950, M7040
Nov 1, 2013
8
0
0
Kewadin, Mi 49648
Where was the crack? Any pics? Just wondering the how and why, pressure on the pipe, vibration etc. something hit/push it?
Maybe I can get some pictures later today, the leak was in the pressure line from the pump to the junction block, believe it was on the upper side, near one of the curves, a slit. I cleaned it up attempted to seal it by welding it with a piece of wire and acetylene torch, then built up a layer of braze, hoping if there were some pinhole leaks, the braze would seal. It worked for a few days, but we are right back, so got to pull the rear right wheel, pull that line, grind it back to where it was and attempt to reseal it. I will likely check on price of the line, but I just replaced a rear plastic fender flap and that was $106, so I'm guessing the line will be 3Xs that minimum. There was no visible impact, just guessing vibration and stress, maybe manufacturing faulty. In any case it is certainly out of warranty. At 72 yrs, I really don't enjoy wrestling those heavy loaded rear tires, but for shop labor prices these days I do what I can.
 

Fruitfarmer131

New member

Equipment
M6040, M8540, M5950, M7040
Nov 1, 2013
8
0
0
Kewadin, Mi 49648
I love my M5950, maybe one day I'll be finished rebuilding it get to work with it.
Ours see limited duty, originally it had a cab, and was used for powering an airblast sprayer. Cab fell apart, and was removed, we have a forklift mast mounted on it, needs either a new or rebuilt high pressure injection pump. It starts, runs, but leaks fuel badly. For a 33 yr old tractor it still is in pretty good shape, only work done was to replace the clutch 2x.
 

Luckystars

Member

Equipment
M5950 M1840A RTV900 CLUB CAR CARRY ALL 1
Mar 1, 2018
98
2
8
Webster FL USA
I just had the injection pump rebuilt $780. A new one runs ~$2800 if you can find one.
I hope I'm done with the overhaul. I did the engine and wires and...... Now I'm painting. I'll use it to clear and level our property for our new home. Also to build the shop/barn. After that it will moving duty on 10 acres.

Good luck with that leak. If it's a crack I've had good luck with Bronze brazing rods as long as the metal is still sound and not pitted or rusted.