Help identify M7040 trans leak. Shuttle valve?

[sixdogs]

I have a cab M7040 Hyd shuttle shift that I bought used with 600 hours. I noticed a trans fluid leak recently and it's coming from underneath and appears to be in the shuttle shift area at the back of engine and start of the "bell housing" area. It's difficult to see because I have to lay on a creeper and the oil origin appears to be up high. It's on the left side of the trans.


Shuttle shift is greek to me and leaks are disturbing so this will be fixed and maybe someone is familiar with what I'm talking about and can offer some commentary. I'm starting form zero so anything or direction is appreciated.

. . .

I can't see where it's coming from but it does look up high.

 

[Gator6x4]

I have a cab M7040 Hyd shuttle shift that I bought used with 600 hours. I noticed a trans fluid leak recently and it's coming from underneath and appears to be in the shuttle shift area at the back of engine and start of the "bell housing" area. It's difficult to see because I have to lay on a creeper and the oil origin appears to be up high. It's on the left side of the trans.


Shuttle shift is greek to me and leaks are disturbing so this will be fixed and maybe someone is familiar with what I'm talking about and can offer some commentary. I'm starting form zero so anything or direction is appreciated.

View attachment 616837 . View attachment 616838 .View attachment 616839 . View attachment 616840

I can't see where it's coming from but it does look up high.

You need a endoscope. I like the Teslong.

https://www.amazon.com/Industrial-Teslong-Inspection-Waterproof-Lithium-Ion/dp/B01HPCPE2Y

 

[5030]

I like the Harbor Freight one better. It's cheaper and in color as well.

On the tractor, the shuttle shift is hydraulic not mechanical. Where is your fluid level at? Looks to me like it's coming from the case vent on top.

 

[sixdogs]

I like the Harbor Freight one better. It's cheaper and in color as well.

On the tractor, the shuttle shift is hydraulic not mechanical. Where is your fluid level at? Looks to me like it's coming from the case vent on top.

Good thinking. I changed the fluid and am very careful but will check that. There is dirt around the oil on the part so that suggests it's been there a while and also it dripped while just sitting. The vent wouldn't drip while just sitting but you never know. Kubotas are very sensitive to an overfill so I'll look and report back.


Gator--On the endoscope, it's a great tool and I'll look into it. Thank you.

 

[5030]

Owning 2 M's, my take is, unless you are getting a puddle on the ground under it overnight, I wouldn't get concerned much. Both mine weep a little bit from the many levers and tings that go through the case casting. I ignore it and wash them regularly (underneath) with a low pressure tip on my pressure washer. Nice thing about hydraulic fluid is, unlike grease, it washes off. besides, it protects the paint...lol

I lose way more fluid (I run Chevron THC All Weather Synthetic) versus Kubota fluid in both mine. Being gear drive (hydraulic shuttle units and not HST), the oil isn't as critical and every time I switch implements with hydraulics (I do that a lot, the Pioneer quick disconnects always pee a little oil anyway). The backside of my M's is usually wet. I just consider it a necessary evil of farming with many different hydraulically operates tools.

The quantity of fluid in your case (mine each hold 54 quarts) pretty much negates any small loss anyway. I can farm all season and loose fluid from the hydraulic fittings on the back and the case weeping a bit and in the fall, the fluid is still within tolerance.

Keep in mind that so long as the fluid shows in the sight glass or in the dipstick (whatever you have), it's all good. In reality, there is enough fluid in the case and Kubota has designed it where the low fluid level (don't show in the sight glass or in the dipstick at all, is still ok. So lonag as there is enough fluid in the case to reach the bottom geareset in the PTO assembly, don't worry. I run a 2 speed double shaft )(exchange type 540-1000 pto on my M's so I can pull a shaft and actually see the level inside the case.

 

[sixdogs]

Well, I went out and gave it a look over the best I could. It does appear the trans oil is a whisker over the top line so here's what I'm now thinking.

My guess is the original owner also kept it at the top line and some fluid came out the breather as things bounced around in field work. That mixed with the dirt already there and made it look like a longer term leak. The fluid could indeed be coming from the vent and that's the best and easiest explanation. To confirm this I'll need to get some fluid out and I can't quite figure out how to do that. I could loosen a filter and see if I can get some out that way but I don't want a gusher so I'm still thinking.

Thanks for helping out and I'll report back.

 

[5030]

I'd just run it the way it is and when it's change time, fill it correctly. The residual hydraulic oil will keep everything lubricated up there and it washes off very easily.

 

[sixdogs]

Something I learned that may help others in the future is that Kubota has it's vents for the gearcase and the front axle set up so that the top line on the dipstick means what it says. If you fill above it, even by a small amount, the excess oil will vent out. If it's on the front axle the vent is above the battery up front and the fan will blow oil all over the place. For the trans, oil will drip out like mine did. Just an FYI.

 

[sixdogs]

Just a footnote on this. If you overfill the trans oil on this series--M7040, etc-- of Kubota, the overage will vent or drip out of the vent in the center of the tractor underneath and you'll think you have a leak. It's no leak and just the overfill coming out.

I have verified this on two M7040's and watched the overfill seep out until down to the max full mark on the dipstick and then stop dripping.