Kubota l3400 hydrulic question

[RDSEILE]

I have an l3400 HST, and when the tractor is sitting on level ground the sight glass is full. But when I run it using the bucket sometimes the fluid totally disappears out of the sight glass and it takes awhile to come back. Does that mean it is ok?

 

[J_J]

If all the cyl are full of fluid and not air, then the only change in the fluid level would be determined by temp.

 

[RDSEILE]

So what does that mean, and is it ok to run? I must mention I just did the 50hr service on the tractor and had all the fluids topped off then.

 

[J_J]

If the fluid is cold and in the middle of the sight glass, that is your cold fluid level. What does your book say about the fluid?

Check the fluid when cold, to see if you are close to fill level.

The fluid will expand when hot and the level of the fluid in the sight glass could change and go above sight glass level.

Work all the cyl about 5 times to purge any air if any, and then check the fluid

 

[MHarryE]

Are you checking it the same way - loader down, 3 point down, bucket curled? Idea is to get all cylinders retracted as much as possible to prevent overfilling. My Kubota book doesn't mention it but other equipment I have does - hydraulic oil has a significant coefficient of expansion so your hydraulic system should show a higher level when hot than when cold.

 

[RDSEILE]

Yes i have checked it with everything down, and when it's cold the level is fine when I run it the level disappears out of the sight glass but it doesn't go over the glass

 

[J_J]

These three things will lower the level of the fluid other that temp.

Lift arms at max up. Base side of cyl full.

Bucket tilt full down. Base side of tilt cyl full.

3pt full up. 3pt cyl max fluid.

Are your hyd operating satisfactory?

 

[RDSEILE]

Yes everything works fine I just wanted to make sure I wasn't going to burn the pump up or the transmission, nothing seems to be slow or sluggish