eBay/Craigslist Back hoe question

jakell2010 · Sep 25, 2011

Hi

I am new to the Chinese board,,,been around here a while though (TBN),,,anyway, I have a 2011 Kubota 2920B series,,,here goes,, surfing craigslist the other day I see " Backhoe 7' used 10 hrs, stored inside $2000", so I go to see it, and this chap had one time tried to start a dealership of Asian tractors and had bought several units to sell, he says when he got it he found that it didn't have a few things like stops for the swing etc. ( he's an engineer),, so it has been slightly modified.,,,but it looks fine, actually like new. What concerns me are the o- ring flat seals,,,it uses this on all fittings, the hoses look like new, but as everyone knows,,,,hoses are meant to be cut.

My needs for the hoe are slight,,,,,mainly around the farm kind of stuff,,,tree stumps,,test hole fence posts, etc.,,,probably won't see much use. This hoe runs off tractor hydraulics. He was running on a 1310 ford, pushing like 5 GPM, it was slow, but worked, . I am having my tractor plumbed for rear hydraulics tomorrow to see how it'll work on my tractor. It's a 3 point type

What do you think, should I not buy this thing,,,for my use a $2,000 hoe is perfect, far less than $8,000

The other thing was ,,the seller said the valve body has no bypass' in it, it has to be run by PB from the loader

Joe

J_J · Sep 26, 2011

Do you have FEL valve with PB?

Are you planning on plugging in to the remote valves for BH?

Detent on the remotes would be a good thing.

Do the remotes have PB?

How many GPM's does your tractor have?

What do you mean by no bypass on the BH valve? Do you mean no PB on the BH valve?

RonMar · Sep 26, 2011

Does the BH have a fluid tank? Does it have it's own pump? It can be run from a PB port on the tractor as long as it has a low pressure return to the reservoir. BH's tend to work the fluid hard and make a bit of heat. Most run their own pump and tank to help deal with this heat.

As for the hoses, every chinese BH I have seen uses the ORFS hoses. Any dealer that imports the chinese hoes should be able to get you replacement hoses if you need them...

Bob Rooks · Sep 26, 2011

ORFS fittings are becoming very common for low volume systems on today's construction equipment, however, the Chinese chose a metric size that's not available through regular sources (18 mm x 1.5).

The seller states the valve stack doesn't have a "bypass"? Of course it does. It has a system relief valve! (this fellow is an engineer?) If you remove the console cover you'll see it on the left side - it's the one with the adjusting screw. This hoe is designed for 7 gpm @ ~2,250 psig. All of the hoses are ~1/2" ID or the metric equivalent, which IMHO is too large for this unit.

Problems/issues you can expect: Piston cup seals in the hydraulic cylinders don't like American formulated hydraulic oil - they will decompose and blow, and fill your system with small bits, and plug the relief valve so you will have little, if any, operating pressure. Been there, done that with my Chinese hoe and so have a lot of other folks. The valves are not easily feathered and it will take some getting used to.

After numerous breakdowns, I finally fixed my Chinese backhoe - I replaced it with a LiTW Korean hoe and couldn't be happier. But that's just my story, several others have reportedly had good luck with them

jakell2010 · Sep 26, 2011

Yes my loader has PB

I am having pressure and return ports put on the back of my tractor from the F.E.L VB

Why would I need an additional remote with detent before the hoe?,, the hoe has it's own valve body which will be supplied with power from my loader VB power beyond port

The seller said that the hoe doesn't have a relief valve inside the VB?,,that I need to run it off my loader valve PB port, which I do have, and which does have a relief

I have 8.3 GPM, the hoe doesn't have a pump or tank , it's set up for tractor hydraulics

RonMar · Sep 26, 2011

Maybe what he meant was the BH valve dosn't have a PB passage. I would be really surprised if it didn't have a safety relief in the valve block. As Bob mentioned, it will be near where the input hose connects to the valve block. On mine it is on the bottom of the valve block just below where the input hose attaches... Some PB ports have detent valves on them so you can turn the flow to them on and off

Is your tractor hydrostatic drive? If it is and you decide on this I would reccomend a return line filter on the return line from BH to tractor, again provided that return is low pressure to the tractor reservoir. I have had domestic fluid in mine for about 3 years now and have not experienced any seal degredation, but a fine filter would help contain any issues from contaminating your tractors system if you should experience any issues...

J_J · Sep 26, 2011

jakell2010 said:
Yes my loader has PB

I am having pressure and return ports put on the back of my tractor from the F.E.L VB

Why would I need an additional remote with detent before the hoe?,, the hoe has it's own valve body which will be supplied with power from my loader VB power beyond port

The seller said that the hoe doesn't have a relief valve inside the VB?,,that I need to run it off my loader valve PB port, which I do have, and which does have a relief

I have 8.3 GPM, the hoe doesn't have a pump or tank , it's set up for tractor hydraulics

Are you going to keep the BH on all the time? If not, you have to connect a short hose from the pressure fitting to the return fitting to keep the flow in series.

You can always plug in a set of remote valves for other applications, like T-N-T, and other hyd driven attachments, etc.

Soundguy · Sep 26, 2011

sounds like a good price for a small hoe.

I picked up a woods 6500 for 2600$ a while back.

I too only need it for 1/year kinda jobs.. but it sure beats a shovel when ya need it.

I 3-pt'ed mine on an old ford 850 and run off a pto pump.

way cheaper than buying a new hoe, and way more convienient than going and renting one for spure of the moment jobs..

soundguy

NuJinma · Sep 26, 2011

There are problems with the chinese hoe. I have one, it has been working for me for 3 years now. If you blow a hose by tightning down the relief valve to much it is a pain getting new hoses with those fittings. The valving is not too smooth but you will get by and has it does have excellent power.

jakell2010 · Sep 26, 2011

JJ,,,,,the Kubota guys didn't mention having to keep the PB flowing by looping it, the valve body on my B2920 is integral on the trans housing , the tractor comes with the loader valve stock,

I thought about putting a filter on the return, what micron size is best?

I see a lot of tractors with coupling that aren't tied together when not in use, what's the difference

Bob Rooks · Sep 26, 2011

jakell2010 said:
I thought about putting a filter on the return, what micron size is best?
10

I see a lot of tractors with coupling that aren't tied together when not in use, what's the difference?
Those are probably closed center systems that allow multiple valves to be used in parallel.

12345

driley · Sep 26, 2011

I bought a Chinese backhoe (Jimna LW7) off ebay this summer. I put it on my Kubota L5450 and run it off the one of the tnt valves. Everything they warn you about them is true. They're loose right from the get go, the valves are difficult to feather, etc. But when you compare the price to a Kubota or equivalent it makes the shortcomings easier to live with. Especially if you plan to only use it a dozen hours a year or so like I do. If I was going to make money with it, I'd pay for the good one. As a shovel replacement for a guy getting too old (or lazy) to dig with a real one, It's perfect.

jakell2010 · Sep 27, 2011

Driley,,,,,,,my exact reasoning, the only thing i am concerned with is doing damage to the tractor, the amour I will use it is maybe 1-2 days per year

traktorz · Sep 27, 2011

ORFS are inch only, never metric.

ORFS standards: SAE J1453 and ISO 8434-3
ORFS (O-Ring Face Seal) fittings have a straight thread and a flat face with an O-ring groove machined in the flat face.

I would strongly recommend to avoid mixing up the Chinese Metric thread flat seat/seal Hydraulic Hose Fittings with ORFS. Primarily, ORFS are never metric threads. Secondary, the Chinese fittings do lack the inner groove wall, thereby risking the o-ring to get sucked into the hose and contaminating the hydraulic system.

Just call them what they are instead (and what the Chinese call them): Chinese Metric thread flat seat Hydraulic Hose Fittings

More on this topic in these referenced threads:

Ref:

traktorz · Sep 27, 2011

I agree with adding a return filter, if you chose to run from the tractors hydraulics. I think it actually is a simple insurance for the tractors own hydraulics. I also strongly recommend to add a tank return filter, if your backhoe is using a separate pump and tank.

One weak spot with the Chinese backhoe is the abscense of grease zerks at the joint bearing for the twin boom swing hydraulic cylinders. Grease them up well, before taking the backhoe in operation, and during your maintenance services.

Also, pay some attention to the mounting of the backhoe to the tractor.

You may also check in advance with your friendly distributor their stock of spare hydraulic hoses if they should break. A hose will break sooner or later on your backhoe...

driley · Sep 27, 2011

jakell2010 said:
Driley,,,,,,,my exact reasoning, the only thing i am concerned with is doing damage to the tractor, the amour I will use it is maybe 1-2 days per year

I understand your concern. There's a lot of messages on this board about people breaking their tractors with 3pt backhoes. I will say that it does seem kind of hard on the three point when I'm digging. Not so much the actual stress but the fact that the linkage slack allows the hoe to move around and can cause jerking type stresses. I'm seriously thinking about building my own frame mount to use if I'm doing something more than a small simple job.

Bob Rooks · Sep 27, 2011

traktorz said:
ORFS are inch only, never metric.

I didn't think I would have to do this:

Surplus Center

ORFS Male/Metric Male

And many more...

But like I said, the Chinese use different metric sizes: 14mm, 18mm, and 22mm.

bluechip · Sep 27, 2011

Most Chinese 7' backhoes are quite heavy, and usually set up for 3 point mounting. I think this will be way too much hoe for a 1600lb tractor. I think there is a good chance you will snap your tractor in two. I didn't like to put the 7' how on less htan 35HP chinese tractors and they are usually 3500lbs or so base weight, and heavy castings. There are some smaller korean, italian, and even chinese hoes that would be better, or a kelly made in usa. of course you won't get them for 2000! If you proceed with this be very careful and you may want to see what it might do to your kubota warranty.

jakell2010 · Sep 27, 2011

The hoe weighs 700 lbs, it is not as heavy as the other 3 pt hoes I have seen,,my bush hog weighs 600lbs and is cantilevered 6' out,,,

Tractor,,I already set up a return filter thanks, i set it up with qiuk connects so I can put it in when I need to use the hoe and take it out for other things

This hoe has grease zeros on all the bearings,, the king pin was modified and replace with a greasable one, Mr Rooks,,I had seen that page from surplus supply, thank you

I have access to a tank and PTO pump, that I may buy for $100 just to isolate it,,,not sure

I still haven't gone thru with the purchase,still weighing the ends against the means , so to say

My tractor has frame mounts in the back and I was thinking about fabricating a backer mount to make it a little tighter, also there are some " more heftier " top links out there that companies like liberty backhoes use

Thank you for all the input