Dumping Loader bucket

[Wannafish]

This is about the only complaint I have after 228 hrs. on my 4010 with the 410 FEL. Sounds like there are a lot of us who thought it was only "our" machine. Please let us know what the technicial says...the only positions I can find are "slow" and "frustrated"! /forums/images/graemlins/frown.gif

 

[JerryG]

<font color="blue">since it's heavier it tends to extend the cylinders faster than the pump can fill them so you end up with a void... You then have to wait till this void is filled with oil again to get quicker response from the loader</font>
That is the exact reason that a regenerative valve is placed in a lot of loader systems. It prevent this from happening. Does this loader have a regenerative valve?

 

[JackIL]

The issue is that not enough oil is being pumped and usually (not always) this means the cause was that the engine was not being run at wide open throttle. The first thing to try is to run at wide open throttle. Usually this will reduce the severity of the problem or eliminate it.

The problem usually occurs when dumping a very heavy load or when backblading. With light loads it may not occur.

On "industrial strength" machines the pump is usually sized large enough so that even with the engine throttled back there will be adequate oil flow to prevent the problem.

Give it a try and then let us know if it helped you.

JackIL

 

[candmgam]

I'm just about to take delivery of a new 4410/430 fel. Any comment on whether I'm likely to see this problem on that equipment, or am I in the 'industrial strength' range - I expect to be using the backblading quite a bit in landscaping work /forums/images/graemlins/confused.gif.

 

[BigEddy]

Deere has Regen on the dump circuits of most of the CUT's.

Push the lever to the right, and the pump feeds oil to the dump cylinders at the rate it is being pumped. More RPM, more oil. You can feather the lever to vary the rate as well.

Push the lever further to the right, past the detent, and the SCV opens a port to allow oil to flow from one end of the cylinders to the other independent of the pump. Gravity will now dump the bucket faster than the pump alone IF you have a load in it. With no load in the bucket, it might be slower than with the pump, as their is little weight forcing the oil around.

I'd experiment with it a bit. Might be your detent is stiff and you can't get into regen / back from regen. That would account for the bucket not staying put while backdragging. You should be able to feel/tell when you go from regular to regen, like you do going into float on the lift cylinders.

 

[deere_x475guy]

I just met the tech at the house. As usuall the symptoms are not showing up now. I did clean it well last night and noticed I had a lot of weeds and just up around the housing on the right side. Could be just had something interfering with being able to move the lever far enough. When it does happen you don't hear the relief valve noise that you usually can when reaching a complete cycle of the cylinders. Or, it only happens when good an warm. I will be doing 80 yards of sand over the weekend and should be able to tell my then. I will let every know how it goes.

Happy 4th to all

 

[beenthere]

That was a good description of the regen system, and explains the 'mysterious' behavior when not having a load in the bucket and pushing joystick to the far right to dump. It is slower when getting into that dump regen position (and not having a loaded bucket). As well, the bucket seems to 'flop' around with no 'control'. Getting used to (experience) the way it works is half the battle.
For a full bucket, the regen works great and dumps the load quickly. Without regen feature, the bucket would only dump at the same speed it curls.

 

[glalonde]

There's an article in the 790 manual which talks about this:


<font color="green">Using Selective Control Valve (SCV) Regenerative Circuit</font>
The SCV has a regenerative or "regen' circuit. "Regen" means that the SCV cylinder is pressurized on both sides.
The SCV can be adjusted to a "regen" position for permitting attachments such as loaders to dump the bucket faster.
<font color="green">To lock out "regen" function:</font>
1. Remove screw (B) and lockout plate (A), located just below the SCV control lever and rockshaft control lever.

M97728

2. Turn lockout plate (A) over and install screw (B) as shown.

M97729

3. Tighten screw (B).



I'm not sure what position is this plate on my 790 (I'm at work).
Also, the sub-title "<font color="green">To lock out "regen" function:</font>" is a bit confusing i.e. does it mean that the circuitry shown in the first picture is in the mode to dump the bucket faster and you can prevent this by locking the regen circuitry ? ... or does it mean it's the opposite that's shown ?

 

[RobS]

Very informative thread, thanks everyone. I've see the same article in my 790 manual, which has only served to further confuse me /forums/images/graemlins/confused.gif

I suppose one of the difficulties with all this is it's hard to get practice. Empty bucket practice doesn't work. I have a new pile of pea gravel, maybe I'll take the time to experiment /forums/images/graemlins/smile.gif

 

[JackIL]

It is possible on essentially all compact tractors with loaders if the engine speed is so low that the pump cannot "keep up. If you find this situation occurring when back-blading or dumping very heavy loads, just boost the engine rpms untill it goes away. By "industrial strength" I intended to imply full-sized loader-backhoes or excavators.

JackIL