Turn up hydraulic pressure on Kubota L39?

DivineL39 · Mar 29, 2020

Ya, Im starting a new thread. This is a separate question. I have researched how to check the pressure that the main relief is set at, and how to adjust it. (I believe mine is set low)
I have ordered a gauge and plan to test my pressure sometime next week. My question is, Has anyone else done this on a similar machine? Spec is 2770 psi max. Is there anybody who has tweaked it up above the suggested max? If so what pressure did you go with, and has it caused any problems? Also one detail on adjusting. The manual shows the location of the "adjustment screw" but doesn't give detail on how to adjust it. Is there a cap to be removed to access it, or is the hex im looking at it? any detail on that would be great.

radios1 · Mar 29, 2020

I know someone who did that on a larger tractor, he broke the FEL arm, and had to have it welded, this was done installing a cesspool.. the pressure is limited for a good reason..

oldnslo · Mar 29, 2020

As a point of reference 100 PSI on 3 inch cylinder is 700 lbs force so increasing pressure 200 PSI is 1,400 lbs force.

Your machine adjust as you want with the understand something might break.

DivineL39 · Mar 29, 2020

radios1 said:
I know someone who did that on a larger tractor, he broke the FEL arm, and had to have it welded, this was done installing a cesspool.. the pressure is limited for a good reason..

Thats exactly the kind of info Im looking for, Thanks. I wonder how much he turned it up? I will say. Unless I hear that someone else has done it, with no problems. I Won't do it to my tractor. But I do hope I find that its set at the factory minimum, then turn it up a few psi to max spec. I wouldn't go over specs without some convincing testimony of success.

DivineL39 · Mar 29, 2020

oldnslo said:
As a point of reference 100 PSI on 3 inch cylinder is 700 lbs force so increasing pressure 200 PSI is 1,400 lbs force.

Your machine adjust as you want with the understand something might break.

So If Mine is set at spec. minimum 2700, and I bump it to spec. max 2775, I should expect 525 psi or so extra strain on my cylinders and arms? That would be a decent improvement. Here is hoping I find it under specs.

Tractor Seabee · Mar 30, 2020

Early on my BX with 1500 hours I raised the pressure from 1780 to 2000 and have had no problems, just the advantage of lifting more with the FEL.

Ron

DivineL39 · Mar 30, 2020

Tractor Seabee said:
Early on my BX with 1500 hours I raised the pressure from 1780 to 2000 and have had no problems, just the advantage of lifting more with the FEL.

Ron

Do you know the specs for the main relief pressure on your tractor? min and max?

Tractor Seabee · Mar 30, 2020

DivineL39 said:
Do you know the specs for the main relief pressure on your tractor? min and max?

1778-1849. It came set at the low end.

Ron

DivineL39 · Mar 30, 2020

Tractor Seabee said:
1778-1849. It came set at the low end.

Ron

Ok, that is some good info.
So roughly you went about 8% over spec.
But ultimately you got about 12.5 % overall increase in pressure.
Im not greedy, that sounds like a nice Bump in potential.
If you have 3" cylinders then that's 1540 Lb force per cylinder = 3080 lb total extra force.
Not sure what that translates to in lift capacity. FEL lift capacity is not my main target though. I save a lot of time and money pushing trees over with the hoe. Thats where I want more oomph.