Backhoe [RPMS] how little is enough?

[ron45]

Being of frugal...STINGEY German stock I sometimes run Kioti at about 1200 rpms when digging out rocks that are not very large. This is just enough to make the controls responsive. Someone told me once that the hoe should be run up near max rpm from the motor or undesirable chemical changes accumulate in the hydraulic oil. He had a term for it but I don't remember it. I asked about it here once but it was long ago. The consensus was not true. So I just wanted to check about the opposite of max rpm, re minimum rpm needed for the the task. Am I hurting anything working this way? I don't get the sense that anything is under powered. These are small surface rocks and they come right up with little perceived effort on Kioti's systems.

 

[4570Man]

Being of frugal...STINGEY German stock I sometimes run Kioti at about 1200 rpms when digging out rocks that are not very large. This is just enough to make the controls responsive. Someone told me once that the hoe should be run up near max rpm from the motor or undesirable chemical changes accumulate in the hydraulic oil. He had a term for it but I don't remember it. I asked about it here once but it was long ago. The consensus was not true. So I just wanted to check about the opposite of max rpm, re minimum rpm needed for the the task. Am I hurting anything working this way? I don't get the sense that anything is under powered. These are small surface rocks and they come right up with little perceived effort on Kioti's systems.

I don't see any problem. I find my backhoe works pretty good at 1200-1500 RPMs. If I am doing anything "serious" digging I run at the suggested 2200-2400 RPMs because it is much faster. When I am using my backhoe thumb for firewood cutting I ideal at an 1300 RPMs. The backhoe operate much too slow at slow ideal, but spends most of the time doing nothing so I hate to run much faster.

 

[Gary Fowler]

I don't think you would do anything to the hydraulics at that speed, but you may not be doing the engine any good running it at prolonged just barely above idle speeds. It could cause a lot of carbon build up and some say it causes 'wetstacking' (WS) where unburned fuel gets back into the crankcase. I never run my TLB at WOT when digging, it is just too noisy and I don't need the extra RPM to make everything work to my satisfaction. I do find that 2000 RPM is about right for what I do and the hydraulics work plenty fast with just as much power, the engine isn't screaming like it is at wide open throttle (WOT)and it is fast enough so there is no WS nor carboning up of the engine.
I would suggest at least 1500 RPM for removing surface rocks and other easy going operations.

 

[murphy1244]

When working my machine I run at 1800 rpm at least to get the hydraulics up to speed and work the moisture out.

 

[ron45]

Thanks 4570 man. I use to have on of those. Traded it for a welder I needed. I've always regretted it. What is a back hoe thumb? That's a new term for me.

 

[ron45]

Yea, noise is the other issue that got me thinking about lower rpms. Didn't know about the wet stacking. I'll try the 1500. Most of the rocks I encounter are not of the surface type and the ones that are don't require much time at all. Then it on to the bigger ones. Worst case might be 10 minutes. In view of that do you feel it would cause problems.

thanks very much for helping,

Ron

 

[ron45]

Thanks Murfy, I often run it there for serious digging. When driving the tractor to where the work is on grades in 3rd gear I am often at 1800. Is just that sufficient to warm up the hydraulic fluid or should I be letting Kioti do some yoga while we go the the work area?

 

[murphy1244]

Thanks Murfy, I often run it there for serious digging. When driving the tractor to where the work is on grades in 3rd gear I am often at 1800. Is just that sufficient to warm up the hydraulic fluid or should I be letting Kioti do some yoga while we go the the work area?

Yoga is always good for the engine and the soul. Let the PTO spin on a cold day too. Zen and the art of tractor repair...

 

[DK35vince]

Its not hurting a thing.
The backhoe will just be slow at low RPM's

 

[Alien]

I sit on 1800 for most stuff (FEL etc) and 2200 for mowing. Main thing to watch for is that the engine is not labouring. (struggling)