Hydraulic (bucket) throttling

[Bugzilla46310]

The bucket on my 2680 is extremely touchy. Seem like it is full go or stop. Other tractors I have had you could operate the bucket much more smoothly very easy. Is there anything you can do to the hydraulic valve to get a smoother operation?

 

[Mark_BX25D]

I have the same question for my backhoe main boom. Up or down, left or right, it's VERY touchy. The dipper and bucket do not have that problem.

 

[Grandad4]

The BX models all have a pretty small hydraulic pump. At full operating rpm you get maximum flow but the output drops off at slower engine speed. If things are too jumpy, try slowing down the engine before looking for more complex solutions.

 

[Mark_BX25D]

The BX models all have a pretty small hydraulic pump. At full operating rpm you get maximum flow but the output drops off at slower engine speed. If things are too jumpy, try slowing down the engine before looking for more complex solutions.

But Scotty, I need more POWER!


Seriously, if I have to slow it down to get it to work decently, that's a design flaw. I would love to find a way to adjust it.

 

[TheOldHokie]

But Scotty, I need more POWER!


Seriously, if I have to slow it down to get it to work decently, that's a design flaw. I would love to find a way to adjust it.

The metering performance of spools in DCVs is primarily a function of gland overlap and edge design. You typically pay more for valves that provide better control of metering but it often comes at the cost of increased spool leakage. Somebody in engineering/purchasing made a cost/benefit decision and AFAIK short of replacing the valve with a better one you are stuck with it.

Dan

 

[Grandad4]

But Scotty, I need more POWER!


Seriously, if I have to slow it down to get it to work decently, that's a design flaw. I would love to find a way to adjust it.

The way to adjust it is with the throttle. You don't need to operate at max rpm all the time. You don't want to putt-putt around at ldle either. The best engine speed varies from task to task.

The BX is admittedly a very small tractor built to meet a particular price point, and it is not as sophisticated as larger, more costly tractors. But it can do an amazing amount of work, particularly in the hands of an operator who has learned how to get the most out of it.

 

[Mark_BX25D]

The way to adjust it is with the throttle. You don't need to operate at max rpm all the time.

When I'm trying to dig in hard soil and deal with roots, I need everything it has to offer. Reaching back to adjust the throttle for every swing of the backhoe is not exactly a practical solution.

 

[Mark_BX25D]

The metering performance of spools in DCVs is primarily a function of gland overlap and edge design. You typically pay more for valves that provide better control of metering but it often comes at the cost of increased spool leakage. Somebody in engineering/purchasing made a cost/benefit decision and AFAIK short of replacing the valve with a better one you are stuck with it.

That's pretty much what I figured, but it's nice to have knowledgeable input.

 

[Crash277]

I can operate mine at full rpm with no problem. But not until I had lots of seat time. I slowly worked up the rpms while getting used to the machine. Rarely is it jerky any more.

 

[0xACE]

I just recently moved to a 2022 BX23S from a 2003 BX1500. I was very fluid with the BX1500 after ~20 years of seat time. The "curve" of the stick is different with the BX23S so my work is also a bit herky-jerky as well. Figuring as stated here, I just need more time working with the new girl to get my motions just how she likes them.

 

[fried1765]

When I'm trying to dig in hard soil and deal with roots, I need everything it has to offer. Reaching back to adjust the throttle for every swing of the backhoe is not exactly a practical solution.

A nice, new, or used L47 TLB would solve your issues.
The L47 has 3 hydraulic pumps!
I have a 2006 L48 TLB which also has 3 pumps.

 

[Mark_BX25D]

A nice, new, or used L47 TLB would solve your issues.

You ain't a bit shy about spending my money for me, now, are ya!

 

[Dustyx2]

Combining boom and swing motions makes it more manageable.

 

[Mark_BX25D]

Combining boom and swing motions makes it more manageable.

Yes, I picked up on that, and I use it. Still, it should not require such careful management.

 

[Vigo]

You can install adjustable restrictors inline on those circuits if you want to, but they do put some heat into the fluid. Some adjustable restrictors offer adjustable flow in one direction and free flow in the other direction, which you may find useful. For example, i would like all buckets to have the option to go fast in at least one direction so you can 'shake' sticky clumps off the bucket when needed. You would also need two such valves if you wanted to adjust the speed to be different in each direction.

Some backhoes have non-adjustable forms of these restrictors from the factory. I found and repaired some such factory restrictors and posted about it in this thread, post #10: Backhoe swing speed restrictors

The idea for restricting bucket movement would be the exact same, just placing the restrictors in a different set of hydraulic lines.

 

[Mark_BX25D]

Ah, like so?

I didn't knwo of their existence. Thank you, I'll look into that.