Bucket Dump Hesitates

[Knight9]

Hi all,

I just got through moving and spreading 10 loads of topsoil (120 cubic yards). All went well and the place looks much better even with just nice dirt...can't wait for grass!!!

Did have one problem that I would like some input on. Occasionally (about one in three dumps) when I had a load of dirt and went to dump the bucket the dump cycle would start, hesitate and then finally dump. Moving the control back to center and re-initiating the dump would sometimes force a smooth full cycle dump properly. Has anyone got any suggestions?? The hydraulic fluid level is fine, the loader pivot points are well greased. Tractor has about 35+ hours on it.

Thanks,
Kevin

 

[DarinRay]

Kevin,

I too experienced the same thing once in awhile and posted this awhile ago in Kubota Owning "Front axles". Here is the paste of the reply from Kubmech. This might be different with yours but am sure you will find out in here. Goodluck

Darin



Re: Front axle seals [re: DarinRay]
Posted by kubmech (Bronze Member)
Posted on 06/16/01 06:58 PM


O.K. Daren here's what I think you may be experiencing:
When you have a bucket full of material and your dumping, the weight of the material tends to cause the bucket to dump faster than if it was empty. This will create a slight air void inside your cylinders. Thus the 'spongy" effect you describe. The increased speed of the bucket dumping exceeds the ability of the cylinder to completely fill on the opposite side. When you power the bucket in the other direction you basically purge the air and the cylinders are tight again. Most likely the same thing with your backhoe just shows up as a different symptom do to the working nature of the two different implements. I can't remember if it was an option in 1996 but they have overcome this problem with a new style loader valve (4 position), That adds a regeneration circuit which ports fluid to both sides of the cylinder and eliminates this effect. I know, if you port fluid to both sides of the cylinder how does that work? Why does'nt it just lock up and not move? I'ts simple once you think about it for a minute. The front side of the cylinder has the rod in it, while the back side does'nt, therefore due to the larger displacement on the backside it overcomes the front side and no more air bubble.

 

[Knight9]

Hi Darin,

If I'm reading this correctly <font color=blue>"they have overcome this problem with a new style loader valve (4 position)"</font color=blue>....then I should have the new loader valve that should have corrected this problem? Is that correct?

Thanks,
Kevin

 

[DaveM]

Hi Kevin,

I don't know if your valve type causes or fixes your problem but I believe all recent B series FELs come with the new regenerative valve. My LA402 did and I bet your's did too! Did you call your dealer yet to pick his brains? BTW, I haven't experienced this problem but I doubt my loader has seen as much hard, honest work as your's.

Good Luck- Dave

 

[Knight9]

Hi Dave,

No I have not called my dealer yet. I still have a fair bit to do in a short period of time here so I will be hitting the 50 hr mark shortly. We negotiated in the 50 hr maintenance to be included, so when they do that I'll have them look at the dump cycle if it is still acting up. No use doing two trips.

The dirt piles certainly put the little Bota through its paces that's for sure!!! The sad (good?) thing is that I have only done the front of the house....the back will likely be another 10-15 loads.....more seat time!

Kevin

 

[DarinRay]

Hmmmm,, You are right I didn't realize how new yours was for some reason. It will be interesting to see what others say now. Boy it's hard to keep up with all the different projects everyone is doing. /w3tcompact/icons/smile.gif

Darin

 

[RichS]

Not sure about the Kubota's control, but when I got my JD every once in a while I would have a similar reaction. What mine turned out to be was that I was actually not just dumping, I was moving the control so the loader was moving up/down and dumping at the same time. This was not a problem if I either had the RPM's higher or had a lighter load in the bucket, or pushed the control so that it was actually only dumping. Just something that I found. Not sure if it will help on your Kubota or not. /w3tcompact/icons/smile.gif


Rich S.

 

[Knight9]

Rich,

Sounds like you are implying user error!!! /w3tcompact/icons/smile.gif/w3tcompact/icons/wink.gifI certainly hope you are right. I'll try and focus next time on a clean move in one direction and see if that helps. But....With the Kubota loader I'm supposed to be able to go "at an angle" with the control and lower/dump or raise/dump simultaneously. Hmmm....makes a guy wonder.

Kevin

 

[RichS]

Yes, in my case it was user error. /w3tcompact/icons/shocked.gif I can go at an angle with mine as well, but I have found that if the combination of low rpm and/or something real heavy in the bucket will cause a hesitation. Low RPM was in my case around 1800-2000 and in addition, I have a hydrostatic. Thus the combination of all, up/down, cycling the bucket and potential of moving with low RPM just wasn't putting enough juice through system. Found that with the Hydro. definitely need the higher RPM for performing these operations in conjuction with each other. Sometimes, I would just get real slow response, Bucket would dump just real slow. Then I thinking. Jeez, my tractor is too tiny. Need more power. Naaaaa, Just smarter operator. /w3tcompact/icons/smile.gif


Rich S.

 

[DarinRay]

Rich,

Now that you mentioned that about rpm's and operator error thing I am starting to look in that direction too. ALthough mine might be a combination of older valve body and operator error. Well now that I'm thinking outloud----I am running my backhoe atmost 1600 rpm's because that just keeps everything smooth running for a slow operator. /w3tcompact/icons/wink.gif Probably is a hydrualic flow thingy. /w3tcompact/icons/smile.gif

Any comments about running at these low of rpm's. I've been reading some post on diesel idles or shut down and see there is sometimes a problem with carbon buildup. If I never see 2000rpms does this bother the motor?? I might reach 2000 when driving up my driveway and thats just about it.

Any thoughts or comments would be appreciated.

Darin