Loader question

[CTyler]

Hi.....I have a L3130 with a Woods 1016 loader. The Kubota operators manual page 56 states the following:

"When using the tractor hydraulic system to power the front loader, do not operate boom and bucket cylinders simutaneously"

Why? What is wrong with doing this? It seems counter productive.

Thanks
Chris

 

[Bird]

Chris, I think if you try it (experiment a little), you'll find out what's wrong with it. Shouldn't hurt a thing, but when you open both valves simultaneously, the hydraulic fluid will take the path of least resistance, which means whichever cylinders have the lightest load will be the ones to move and the others won't move until those reach their limit of travel. Took me a little while to get used to that system with the LA401 loader on my B2710, but it's really not a problem once you get used to it.

 

[Anonymous Poster]

Bird and all,

That's really interesting and makes sense. BUT, the funny thing is that I did not notice that with my B2910 and La402 loader.

I did a lot of moving of dirt with my loader last summer after getting my tractor...I can't wait to try it when the weather gets warmer [or maybe when the snow piles up a bit more...already been out there once today].

I do know with my backhoe, I can do several movements at the same time...swing, raise boom and curl bucket for example. I just never thought I couldn't do the same with the loader so I did not pay attention I guess. /forums/images/graemlins/tongue.gif

 

[CTyler]

I have been using both at the same time as well but usually on the down side. Lowering the boom and curling the bucket after a dump. Yesterday I was moving snow and used both on the up side as well. This was to make big snow piles for the neighbor kids. Both seemed to work together ok.

Evidently I missed what the manual said the first time through. After reading it today.......Dohhh!!! Just wanted to understand the reasoning. I found it confusing as well because l have a backhoe and you need to use multiple functions at the same time.

Thanks for the responses.

 

[JATO_RaT]

There has got to be more to it then what we are understanding. Using both loader lift and extend/retract on the bucket hydraulics is something that Kubota has made clear you can do. " A regenerative dump circuit allows for fast bucket dumping and the series circuit provides for simultaneous operation of the boom and bucket." That is a quote taken from one of their brochures. Rat...

 

[rbargeron]

The valve is Woods? Does it have two levers? Snow may not be heavy enough to make the hydraulic oil flow to the other spool, but a bucket full of rocks might be. Bird's point makes good sense. The other comments are right too- but apply to the Kubota valve.

 

[JATO_RaT]

That would seem to be the case. My neighbor bought a Yanmar that uses the separate valves instead of a joystick. If using the two at the same time, its the one with the least amount of resistance thats going to profit with oil flow. Not sure why they used that design other then to save cost.

 

[CTyler]

Hi, the loader has a single joystick controller. I called the dealer today and talked to several people and they do not know why this is in the manual. The dealer stated that they do it all the time. I'll write Kubota an email and see what they say.

 

[CTyler]

You may be correct with a heavy load the boom could lower while curling. Maybe a liability thing?

Maybe it just specific to the two stick configuration? That leads me back to the backhoe needing multiple functions at the same time. The BH has seperate sticks maybe the BH valves are different?

 

[jrlichina]

It has nothing to due with how many "sticks" it has but rather the type of valve. Loaders have a 2 spool valve and can be configured with either two separate control levers or one combined lever(a Joystick). The difference is some loaders have a series circuit valve while others may have a series/parallel valve. Meaning the connection between the two separate spools is one or the other. A series circuit valve is really only good when you want to use only one valve at a time. While a series/parallel valve allows multiple valves to be operated at the same time(like a backhoe valve). When two or more valves are operated at once, the cylinder that needs the least pressure will operate first, then the cylinder with the next least, and so on.(like Bird said earlier). Here is a small side note. The valves can be a one piece valve the most typical for a loader or can be of the stacked type most typical of a backhoe. The stacked valves can have different types of work sections to make up one big valve. So you could have one valve be a motor control, one a double acting valve, one a single acting, or 4-way with float, etc.. One piece valves can also have different types of valves too. It's just that with stacked valves you can build what you want. I've rambled on enough so I'll just stop now...