Go Bottom Go Bottom

Metal hydraulic line burst B2400 Kubota

View my Photos
Pigtyme
Join Date: Jul 2003
Posts: 11 Anderson, SC
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster

2002-10-19          43989

Just want some ideas on what could have caused this. This B2400 was purchased new in 1998 and has been used mainly for grass cutting. I added a LA352 loader about three months ago. The tractor only has 292 hours and has always been kept inside and maintenanced beyond recommendations. While using the loader to carry some rolls of sod a few days ago the loader started moving very slowly. Then I smelled hydraulic fluid and found it gushing from the left side of the rear pump where the metal hydraulic line connecting front and rear hydraulics bolts onto the drive pump, right under right side of drivers seat. It just seems strange to me that a metal line would fail with only 292 hours and right after installation of the loader. I don't know how it could have been damaged or if it was just a bad part to start with but you know that it was an expensive repair ... they had to take the tractor apart to get old one out and new one on.

Anyone had a problem or any ideas on the cause? I don't mind paying for repairs on something I did or wore out but I figured I paid for superior quality up front and should not have something like this go bad at such low hours on a pampered tractor ...


Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
Peters
Join Date: Feb 2002
Posts: 3034 Northern AL
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster  View my Photos  Pics

2002-10-19          43991

The metal line should not break. The only reason that the line would break is if the line was damaged, rusted or had a defect in the forming at the factory. If there is no evidence of damage or rust I would look to Kubota for a replacement. Despite the fact it is out of waranty a safety problem like this need to be tract down as to the problem with supply and Kubota should replace. ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
Pigtyme
Join Date: Jul 2003
Posts: 11 Anderson, SC
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster

2002-10-20          44027

I questioned my dealer some more about this failure so I would have at least followed "chain of command" before contacting Kubota HQ. Dealer says he believes that pump was out of adjustment and over pressurized the line causing failure. Line was not externally damaged or rusted. My arguments are:

1) I did not know that you could adjust pump pressure and sure never saw it in my maintenance procedures. It is strange too that you can adjust a pump, which is full of seals and gaskets, to blow apart a metal hydraulic line. Does not sound like good engineering if true.

2) Wouldn't that be something the dealer should have checked when installing a new loader and changing hydraulic fluid just hours before the failure?

Interesting that new line does not follow path of old line. It has a "gentler bend". Makes me think trouble has surfaced before and has been reengineered. Anyway dealer says his hands are tied since tractor is out of warranty but wished me well in my contact with Kubota HQ. I did e-mail Kubota from their website and I am waiting for reply.

I love my tractor and have had nothing but good experiences with both dealer and Kubota up to now ... I will let you know what comes of this. Thanks ... Robert ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
DRankin
Join Date: Jan 2000
Posts: 5116 Northern Nevada
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster  View my Photos  Pics

2002-10-20          44029

You may grow old and grey waiting for Kubota to answer phones or E-Mails. I have been waiting for a return phone call for a month and an e-mail did receive an automated response after a 3 week wait.
My suggestion? Get the name of the area rep and call him every day until he calls back, or call the area distribution center and make a real pest of yourself.
But I still would not hold my breath while I waited if I were you. ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
ThomasG
Join Date:
Posts: 1
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster

2002-10-21          44033

As far as I know, pumps generally aren't adjustable, at least by ordinary maintenance routines. Max system pressures are usually set by a pressure relief valve rather than anything to do with the pump. I suppose the dealer could have meant the relief valve, and a stuck relief valve would raise an issue of over-pressurization. I suppose it's possible that installation of the loader could have interfered with relief-valve operation.

However, even if the relief valve isn't protecting the high-pressure line, design should be such that ruptured lines aren't likely. SAE standards in the '70's called for lines rated for four times systems pressures. If that standard were used, the lines should be rated in the vicinity of 10,000 lbs. I don't think that the gear-type hydraulic pumps generally used on tractors are capable of withstanding anything approaching 10,000 lbs.

This seems like a good place to repeat a hydraulics basic. Pumps don't develop pressure, loads do, and pumps are rated for how much pressure they can withstand. It would have been the loads of sod that produced high pressures, not the pump. Unless the loads were especially heavy for the loader, pressures shouldn't have approached a relief valve setting, let alone the pump's peak pressure rating, which should be a decent measure of max system pressure.

When the loader was working, you might have noticed if the relief valve was working. With especially heavy loads or a valve held open for a few seconds when the loader is at the limit of it's travel the relief valve should open and a scream should be heard. If you've heard that sound, then the relief is likely working and max pressure should be around 2,500 lbs.
....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
Art White
Join Date: Jan 2000
Posts: 6898 Waterville New York
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster  View my Photos  Pics

2002-10-21          44036

I haven't seen or heard of any problems that you have described. We did just do a service call on a leaky line from a loader installation but that is it. I would try and talk to the dealer support staff and find out who put your loader on and checked it over. I would be digging deeper. ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
Pigtyme
Join Date: Jul 2003
Posts: 11 Anderson, SC
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster

2002-10-22          44088

Well Kubota did reply to my e-mail telling me that it has been transferred to its Southeast Support Division for consideration. I guess even that reply is encouraging. I am pretty hydraulic ignorant so I have to rely on what the dealer tells me and bring to you more knowledgeble board members his words for a "truth check". What he said just did not make sense to me even with my limited knowledge. I am sure that the loader was not overloaded with the sod though. I was hand loading the rolled pieces of sod and they were fresh and fluffy weighing only 20-30lbs each and could only get ten at a time loaded. Loader is working well again though and I still love my tractor ... put out 28 yards of mulch this morning with barely a sweat and no aching back. Tractor is still the best working toy I have and is a fine piece of equipment. I guess nothing is perfect no matter how it is built. I will keep you posted. Thank you all for information. Robert ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
Peters
Join Date: Feb 2002
Posts: 3034 Northern AL
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster  View my Photos  Pics

2002-10-22          44089

Stay at them either the dealer or Kubota has made a mistake one need to come clean.
If you consider the break force when you are loading earth from a pile, the sod in the bucket should not be a problem.
I loaded sod this summer and do not recall it being overly heavy. I certainly have had heavier loads of wet soil in the bucket. ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
TomG2
Join Date:
Posts: 1
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster

2002-10-23          44100

I guess it's pretty obvious that I don't think much of the 'over-pressured' explanation. I'd stay with the Kubota CS folks and maybe think that the dealer just used some convenient words. the works might not have come from a technical person.

Since the loader is now working, I would run the bucket to the limit of it's travel, continue to hold the valve open for a few seconds and listen for the relief valve. If the relief valve is working, there's virtually no possibility of pressures on the tube exceeding the system pressure. Irrespective of whether the system is obstructed and the relief valve stuck, components should be capable of withstanding the max pressure the pump could generate.

I also doubt that high-pressures from excessive loads were ever present. Keep in mind that pumps don't make pressure on their own. However, much higher pressures than the load itself can results from bumps hit while driving or dropped loads. However, the steel line is exposed to load pressures only while actually lifting. I suppose a lift or bucket could be made while the tractor was moving and a bump might be hit. A shock load would be generated. However, even if the relief valve was stuck, most loader valves have safety valves on the cylinder lines to protect against load shocks. 3PH's have safety valves as well, and typical safety relief pressures are around 3,200 lbs. compared to 2,200 lbs. for the system valve. If a loader valve is open, the safety valve would protect the steel line against high-pressure. Anyway, it's really stretching trying to reason that operation or even a combination of part failures could expose the line to pressures that it wasn't designed to withstand.
....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
Art White
Join Date: Jan 2000
Posts: 6898 Waterville New York
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster  View my Photos  Pics

2002-10-23          44109

When you are talking to your dealer have him reference his service bulletins on the B-2400 and he will find that there was an update that put an additional clamp and a longer collar to stop the vibrations from doing as you have. ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
Pigtyme
Join Date: Jul 2003
Posts: 11 Anderson, SC
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster

2002-10-23          44131

Thanks ... I will call him in the morning because, unfortunately, I have not heard a peep from Kubota since being forwarded to Southeast CS. Just by chance is there someplace on the web you can find service bulletins for Kubota equipment? Robert ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
Art White
Join Date: Jan 2000
Posts: 6898 Waterville New York
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster  View my Photos  Pics

2002-10-24          44153

Wish I could say yes to tthe on line service bullitins but I can't. I have a lot of running to do friday and saturday delivering new machines but if I get a chance to before the first part of the week I will get the numbers for you. This is not something that Kubota will pick up the tab on but I believe as well as my Kubota rep that is the problem. He did know of the problem when we were talking but couldn't give me the numbers. Manufacturers often do updates like these as when they built these they were not aware of the problem. Some things need more than the controled environments when doing testing to bring out the faults. The new line would have the collar added and normally the parts books will show the extra clamp in all revisions. ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
A HappyPigtyme
Join Date:
Posts: 1
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster

2003-01-14          47502

Kubota came through for me. Mr. Brown from Southeast Division called and had me contact dealer who reimbursed me for the repair. They were slow in responding but Hey ... worth the wait. Tractor is doing great and is getting a toothbar installed as I type. Going to go dig something! THANK YOU KUBOTA FOR STANDING BEHIND YOUR PRODUCT! ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
jeff r
Join Date: Jul 2003
Posts: 428 burton. michigan
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster  View my Photos  Pics

2003-01-14          47529

Pigtyme,

Make sure that dealer puts a test hydro gage on and sets the relief valve for the pressure recommended. You would be surprised at the looks you get when you ask if the the relief pressure was checked. My dealer installed a new Wood's FEL, relief pressure WASNT checked, and FEL lift capacity was real wimpy. I made my own test gage after loader relief pressure capacity was 300 pounds short and prompty went to the installing mechanic and politely showed him the errors of his ways. Needless to say he was humbled.
Betcha he checks them ALL now. ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
Pigtyme
Join Date: Jul 2003
Posts: 11 Anderson, SC
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster

2003-01-15          47540

Thanks for good advice! ... They did check out valve when repair was done. I have used the machine in some tough work since and the loader seems to operate well ... was very fast, strong and smoothe. Getting tooth bar to help grip and rip roots close to surface. Also should help in picking up debris piles. I am a happy Kubota owner. ....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo



Metal hydraulic line burst B2400 Kubota

View my Photos
alcockt
Join Date: Aug 2005
Posts: 1 michigan
TractorPoint Premium Member -- 5 Tractors = Very Frequent Poster

2005-08-10          114656

please contact em in regards to the b2400 line bursting,,are ther eservice bulletins on this, warranty etc
....

Reply to | Quote Post Reply to PostQuote Reply | Add PhotoAdd Photo


  Go Top Go Top

Share This
Share This







Member Login