BX25 Hydraulic pressure, what should it be

[forceten]

I bought the bxpanded kit.

Tested my BX25 after I got the 50 hr service done and swapped all the trans fluids.


No real spike - it went and hit and stayed at 1650 ish

Put in some shims - to bring it up to 1850


Was thinking that might be good - didnt want to push it too much higher and 200 psi should make a world of difference.


But is 1850 ideal? I see some others have gone to 1900 - 1950 and even 2k

I know 1650 was too low (factory set)


For those that have tested and even adjusted. Where is the ideal psi for you and why?

 

[North Idaho Wolfman]

I changed your thread title as what you're asking about is the Hydraulic pressure, not the HST pressure.

 

[85Hokie]

I bought the bxpanded kit.

Tested my BX25 after I got the 50 hr service done and swapped all the trans fluids.


No real spike - it went and hit and stayed at 1650 ish

Put in some shims - to bring it up to 1850


Was thinking that might be good - didnt want to push it too much higher and 200 psi should make a world of difference.


But is 1850 ideal? I see some others have gone to 1900 - 1950 and even 2k

I know 1650 was too low (factory set)


For those that have tested and even adjusted. Where is the ideal psi for you and why?

Mine was at 1750 ish - used the same kit - got mine closer to 2000 - it too made a world of difference! However - after a period of fluid getting hot, you can feel it get "weaker" - but that is simple hydraulics and fluid dynamics. But those little shim(s) make a huge difference!

 

[forceten]

I changed your thread title as what you're asking about is the Hydraulic pressure, not the HST pressure.

Thanks - true its not the transmission pressure I'm adjusting

Mine was at 1750 ish - used the same kit - got mine closer to 2000 - it too made a world of difference! However - after a period of fluid getting hot, you can feel it get "weaker" - but that is simple hydraulics and fluid dynamics. But those little shim(s) make a huge difference!

I tested mine hot. Wondering if I should shim it up another 100 psi to 1950.

Any negatives to having it that high? or is the BX at that psi no problems? I don't have my FEL or backhoe on right now so I cant test the 200+ I already put on. I'm sure I will feel that. Not sure how much more difference another 100psi will make

 

[redfernclan]

I started at 1750, went up to 1950 and am very pleased. Sure, you can go more, but I believe that one reason Kubotas last so long is that there are not cranked way up. I also believe that anything with a FEL should be able to pick the front end up, and mine would not, till I raised it.
I spent ten years as a heavy equipment mechanic and feel comfortable at 1950. More power, but not too much to the point it is overloading things and being to hard on stuff. You can tear any piece of equipment up. Kubota just makes it harder with lower pressure. You can work them hard without destroying them, just use some common sense.

 

[lugbolt]

They keep the pressure low because pressure builds heat. The BX doesn't hold a lot of hydraulic fluid and doesn't have a cooler to speak of, just a fan on the drive shaft that blows air over the HST. Just like a lawn mower.

I hear the complaint of "weak" hydraulics on the BX's often. It is mostly due to not running the engine at rated speed (3600 RPM) when operating. Idling, it's just a little tiny pump that needs speed to make pressure and flow. Sometimes I find that an owner bought less tractor than they needed.

 

[I C Bonz]

hey All

Does shimming for higher PSI void the warranty?

Jake

 

[85Hokie]

They keep the pressure low because pressure builds heat. The BX doesn't hold a lot of hydraulic fluid and doesn't have a cooler to speak of, just a fan on the drive shaft that blows air over the HST. Just like a lawn mower.

I hear the complaint of "weak" hydraulics on the BX's often. It is mostly due to not running the engine at rated speed (3600 RPM) when operating. Idling, it's just a little tiny pump that needs speed to make pressure and flow. Sometimes I find that an owner bought less tractor than they needed.

Lug,

I hear ya - much like any oil - once the temps get up there, the viscosity get up there and flows better than "water"! And I cannot agree more about pump speed. Too many baby the engine and hydraulic power is directly related to the spinning of the pump.

Now, running the BX at 3600 rpms? I might have ta disagree wit cha there , if I push that throttle arm all the way, not sure I can hit 3.6k My little girl has seen 3400 ish - I think I bent the arm then! But I do know that running the engine at 2200 is barely enough to raise the bucket! I like to run mine at 3000 most of the time - if I need more, I goose it and even at 3400 - there is a difference to be seen between those two. And as for cooling, you right again - aint a lot of that going on there either.