Kubota L4400 Hydraulic Fluid Level

Old 08-27-19, 05:38 PM
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Post Kubota L4400 Hydraulic Fluid Level

Kubota L4400

I have searched the internet over & I cant find a clear answer.

I have a leak (drip) under the transmission case but I cant tell (yet) where its coming from. It could be a gasket or a line etc.
But my question is the hydraulic fluid level. On the L4400, there is a sight glass on the rear of the tractor below the seat near where the 3 point hitch connects onto the tractor. Its only a small round sight glass about half the size of a dime. The fluid is clear so its hard to tell if there is fluid present or not. So, you have to get the level just right by moving the hydraulics just right so you can see the bubble at the top of the fluid in the sight glass.
The problem is, every web site I have found that discusses this, talks about how to position the bucket & other optional equipment that I dont have on mine, to get the fluid up so you can see the bubble on top of the fluid.... in the sight glass.

There is no dip stick on the filler cap. So, I took a stick & put all the way down to the bottom of the tank & there is only about 3" on the stick. I would say the tank is 12"+ deep. I know its low but I dont know how low & dont know how to set the implements / 3 point hitch to get the fluid to the proper level for an accurate reading.

The problem is, EVERY discussion I read on this says "DO NOT OVERFILL". It can cause damage (air bubbles/cavitation etc). It was stressed every place I read. Also, low fluid levels can also cause damage for obvious reasons.
Again, the problem is, I dont know how low it is or how much to put in because there are no instructions in my situation. Why in the dickens they didnt just put a dip stick on the filler cap, I dont know.

Bottom line here is, If no one here knows, I'll have to take the tractor 90 miles round trip to the nearest dealer just to find out & get oil added.
Old 08-28-19, 01:11 AM
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On my JD2100 I have the same sight glass and the instructions say for the fluid line to be right across the sight glass.

Doesn't matter what hydraulics you have or dont have, they eventually fill and the fluid is captured in them so all you are doing is keeping the trans at the full level!

So assuming your low, just keep adding a bit every time you use till the level comes up.
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Old 08-28-19, 02:39 AM
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On my NAA it says to check the hydraulic fluid level with all cylinders up. My tractor does have an aftermarket bucket but if you took that out of the equation you'd still want the 3 pt hitch raised when you check the fluid level. My dipstick is on the side of the housing with the cap under the seat.

I doubt there would be any harm to the system if the fluid level is a little low or a little overfilled. Hopefully you can get it figured out. Once you figure out the correct level - take a stick, measure the fluid level inside and mark the stick for future reference. I know I wouldn't want to trailer my tractor any distance just to have a fluid level checked.
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Old 08-28-19, 04:47 AM
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Basically just reiterating what Marq said, but you want the fluid level in the sight gauge just as they prescribe, with or without a bucket or anything else. The reason they elaborate on the bucket is that this same fluid operates the cylinders on that, so depending on how the bucket is positioned at any given time the level may show low when in fact it is not. Without the bucket, your level will always be the same. And yes, it is hard to see some days.

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