BT600 hydraulic line sizes and problems

[Tractor Gal]

If anyone has a BT600 backhoe and can help with this, I'd be most grateful.

The six hoses that come from the control valve to the boom/dipper/bucket all are "crammed" under the boom cylinder hook up area. And, when I say crammed, I mean crammed.

I cannot find any specs on these hoses as to whether they all should be the same OD. It seems that return hoses are larger on some equipment (so I'm told) but I don't know if this is the case here.

The six hoses are contained in a mesh sleeve of some kind to reduce friction so that sleeve also takes up some room. I've seen the diagram in the WSM of how the hoses are to lay in there but they just don't lay right.

I've just replaced the hoses on the boom cylinder so I had to re-attach the boom rod with those hoses under it. I could hardly do it. And, it seems that with that tight of a fit, the hoses are going to need replacing again sooner than later.

So: what are these hoses to be of the same outer diameter? I know they are 1/4" inner diameter. I had a hose made locally and even though it was 1/4" ID, it was not the same OD as the hose I took with me to have made. They said they only carried that one OD size.

Any help or suggestions would be helpful. Thanks.

TG

 

[North Idaho Wolfman]

That is an issue with Hydraulic hoses.
There are thin wall hoses that are original equipment and most aftermarket makers do not deal in them.
I can't think of an easy work around for the lack of space.
I just looked and you can buy the OEM hoses for it.

 

[Tractor Gal]

That is an issue with Hydraulic hoses.
There are thin wall hoses that are original equipment and most aftermarket makers do not deal in them.
I can't think of an easy work around for the lack of space.
I just looked and you can buy the OEM hoses for it.

I have purchased the OEM from the dealer. Too large OD for this tight tolerance. They offer no explanations. Go figure. I guess I'll live with it for now...as if there are other choices.

TG

 

[GreensvilleJay]

hmm. OEM hoses HAVE to fit... it's what the OEM used to make it.......
However it may be a 'game of Tetris'. You need to insert them in a certain order or sequence to get them in properly. I learned the hard way to take LOTS of pictures BEFORE tearing down 'tight' stuff. It usually helps , also recording the 'removal sequence' helps when you get to installation time.
It'd be great to see another BT600 to look at how they're laid out and IF the new hose ARE the same.

 

[TheOldHokie]

I have purchased the OEM from the dealer. Too large OD for this tight tolerance. They offer no explanations. Go figure. I guess I'll live with it for now...as if there are other choices.

TG

Hose OD varies depending on brand and construction. If its that tight you need to do some shopping in the catalogs. What is the OD of the originsl hoses?

 

[PoTreeBoy]

Yes, all 6 hoses will be the same rating and size. Can you measure the OD of your old hoses? The 1/4 R1 hose from Discount Hydraulic Hose measures 0.53" OD.
I'm guessing your dealer made the hoses from the hose and fittings he stocks, not truly OEM.

 

[Tractor Gal]

Thanks for these replies. The answers would be logical is everything else was equal. But, it's not.

The backhoe has probably had new hoses at some point. This setup is a 2004 MLB BX23.
I purchased OEM hoses from the dealer for this backhoe just this week. One of them is larger OD than the other. When I picked up the hoses, I asked about the specs of the hoses and the guy didn't know and I said mentioned about the small space. He, however, was of no help.

In the WSM, there is a diagram for the placement of the hoses at the location. Three go on the bottom of that junction and 3 go on the top of the bottom three. I have tried to follow the diagram but 4 of these 6 hoses are larger OD than the others so it isn't possible.
I just don't know how/where to get the OEM specs so that I can go from there. Or, if nothing else, it would prove that I am crazy...which I don't doubt in most cases.

Sadly, I don't know how to order the correct OD hoses, especially since I'm not sure which of the current hoses are actually OEM. As I mentioned, before I began to replace these due to leaks, it was easy to see that some were large OD than others. I had one hose made at a local shop and when I said it was not the same OD as the one I brought as a pattern, the guy said it was 1/4" ID and that was the only 1/4" hose they stocked. That's why I ordered the OEM from the dealer but this did not solve the problem.

The tolerance in that space is so small that it's "non-negotiable. " I thnk that is why leaks have developed. There is continual friction and pressure at that location. Add the thickness of the sleeve and it's even worse when the hoses are too large at the start.

PoTreeBoy, your info may be the answer, as I re-read what has been posted. I'll try to measure with my micrometer so that I'll have more info. I would've ordered from Discount Hydraulics but I just haven't gotten the "terminology" for the fittings, etc. I know it's J16 but I don't know the size of the connecting ends. I see the pictures and can see the 90 degree etc., but I didn't want to order and then it wouldn't be right. So, I've got the dealer stuff and it will work...crammed in there as it may be. I hope to be ready when one of these pops in the future!

Thanks for all the help. I am learning...slowly, perhaps...but I am learning.

Is there a way to contact Kubota headquarters for questions like these? That may be the best approach since the dealer where I bought these is not helping.

I hope this explains this. Maybe I'm missing something that this explanation will help uncover.

 

[Tractor Gal]

That's another reason I wondered if the return hoses would be larger OD? The neighbor said that is often the case.

TG

 

[North Idaho Wolfman]

The return line is only the line from the BH valve to the tank on the tractor, I don't think yours is larger.
Both lines to the cylinders are the same size interior and should be same size exterior.
One thing that drastically effects exterior diameter is hose construction, like on wire 2 wire, abrasion resistant and such.
Post up what size you have, and what size did fit in there before and I can see if we can get you the hoses you need.

 

[Tractor Gal]

I will measure the hoses with a micrometer tomorrow. There has never been a good "fit." Yes, they are in there but it was quite a task. Friction will definitely be a problem.

I changed one hose earlier and it was at that time that I saw the big difference in hose sizes. I had gotten that replacement from Messick's. I went with the local dealer this time for 2 hoses since they can put parts order with their weekly order and there is no shipping. I was going to be near there so it wasn't spending gas. Another hose, as I mentioned above, was from a local hydraulic shop.

But, I will measure because it's good to know. Because I've just purchased these hoses and the backhoe is back together and working...no leaks...I don't want to buy more hoses at this point. The one from the Kubota dealer was $95!. Ridiculous.

TG

 

[TheOldHokie]

I will measure the hoses with a micrometer tomorrow. There has never been a good "fit." Yes, they are in there but it was quite a task. Friction will definitely be a problem.

I changed one hose earlier and it was at that time that I saw the big difference in hose sizes. I had gotten that replacement from Messick's. I went with the local dealer this time for 2 hoses since they can put parts order with their weekly order and there is no shipping. I was going to be near there so it wasn't spending gas. Another hose, as I mentioned above, was from a local hydraulic shop.

But, I will measure because it's good to know. Because I've just purchased these hoses and the backhoe is back together and working...no leaks...I don't want to buy more hoses at this point. The one from the Kubota dealer was $95!. Ridiculous.

TG

This is why I popped for a hose crimper. The cost of purchasing custom hoses is prohibitive. The local Parker store can make that $95 hose from Kubota look like a deal. At $10 per foot and $25 each for fittings it adds up fast!!!

Dan

 

[GreensvilleJay]

sigh, what a nightmare !
As a starting point, ALL of the true OEM hoses 'should' have a Kubota part number on them and match with the drawing/parts list, well hopefully.
since 4 of the hoses are bigger OD, my 'gut's telling me they're NOT OEM
I suspect the OEM hoses are 'single braid', the fat ones are double(higher pressure but NOT as flexible)

I'd take picture of each, measure them and try to see how they get installed,maybe even make a cardboard 'tube' similar to the boom dimensions to practice on ?

The sad thing is some guy(or gal) on the assembly line did this in 15 minutes so it should be THAT easy..
I'd be tempted to have the dealer order all six hoses and get a price for him to install them1-2 hrs ??). Then when you can't (wrong hoses.,too big) ,get him to install them for free.

sure hope you find a solution soon.

 

[L35]

My BT900 is very similar design. I have replaced most of the hoses and will say the failures except for 1 have been everywhere but the confined space. I honestly don’t see why the bunch can’t be run externally around the tight spot as long as you are careful not to snag them on anything. Some hose control methods to keep them close to the tractor can probably be used to help with that.

 

[Tractor Gal]

My BT900 is very similar design. I have replaced most of the hoses and will say the failures except for 1 have been everywhere but the confined space. I honestly don’t see why the bunch can’t be run externally around the tight spot as long as you are careful not to snag them on anything. Some hose control methods to keep them close to the tractor can probably be used to help with that.

It would be hard to run the hoses externally because the boom folds and it "nests" with the base. Hoses would be crimped in that space. Good idea, though. And, maybe there won't be problems any time soon. I can hope for that.

TG

 

[Tractor Gal]

sigh, what a nightmare !
As a starting point, ALL of the true OEM hoses 'should' have a Kubota part number on them and match with the drawing/parts list, well hopefully.
since 4 of the hoses are bigger OD, my 'gut's telling me they're NOT OEM
I suspect the OEM hoses are 'single braid', the fat ones are double(higher pressure but NOT as flexible)

I'd take picture of each, measure them and try to see how they get installed,maybe even make a cardboard 'tube' similar to the boom dimensions to practice on ?

The sad thing is some guy(or gal) on the assembly line did this in 15 minutes so it should be THAT easy..
I'd be tempted to have the dealer order all six hoses and get a price for him to install them1-2 hrs ??). Then when you can't (wrong hoses.,too big) ,get him to install them for free.

sure hope you find a solution soon.

Several issues to get the dealer to install. One of the main ones is that I don't have a trailer to take it there. Another main reason is the cost. $400+ for the hoses plus $200 install? Just guessing. These reasons are why I try to do things myself. Having "consultations" from members here helps me do that. Plus, I don't see a dealer reverting to no charges with hoses. But, I could be wrong.

As far as the ease...maybe for some. But to have to remove the boom cylinder from inside the boom...that took some doing. Henro recently gave me several suggestions for accessing that boom cylinder. The WSM did not bother to explain all the issues.

Thanks again for all the suggestions. For those with lots of tools, etc., as well as a shop for these kinds of things, this kind of thing is simple. Next time (and I hope there isn't one too soon), it would be more simple for me, too.

TG

 

[Tractor Gal]

A little late to the party in measuring the BT600 hoses, but I checked them today. In fact, I took a picture with my phone but couldn't get it sent to this computer so I can't post it.


Sizes in inches measured as outer diameter:
Smallest hose size: 0.4900
Largest: 0.672
Mid-size: 0.5313

My guess is that the smallest hose size is an OEM. And, this
size may not be available any more. Plus, in thinking this through,
I don't see a dealer selling something that wouldn't fit. That doesn't make sense.

So, while I am trying to place them as the diagram in the WSM shows, it is not working well. Add to the hose size is the mesh size and that mesh has some "wrinkles" in it that would make it take up even more space. They are all in place and working so I'll just need to be happy with that, for now. At the next leak, I'll be back.

I will call discounthydraulics tomorrow to check on the smallest OD hose that is 3000 psi or better. This tractor generates 1850 psi...I bought a hydraulic pressure measurement device from Bxpanded because I wanted to know. Inquiring mind, you know.

Thanks for all the good help. Once again, all of you are top notch.

 

[TheOldHokie]

A little late to the party in measuring the BT600 hoses, but I checked them today. In fact, I took a picture with my phone but couldn't get it sent to this computer so I can't post it.


Sizes in inches measured as outer diameter:
Smallest hose size: 0.4900
Largest: 0.672
Mid-size: 0.5313

My guess is that the smallest hose size is an OEM. And, this
size may not be available any more. Plus, in thinking this through,
I don't see a dealer selling something that wouldn't fit. That doesn't make sense.

So, while I am trying to place them as the diagram in the WSM shows, it is not working well. Add to the hose size is the mesh size and that mesh has some "wrinkles" in it that would make it take up even more space. They are all in place and working so I'll just need to be happy with that, for now. At the next leak, I'll be back.

I will call discounthydraulics tomorrow to check on the smallest OD hose that is 3000 psi or better. This tractor generates 1850 psi...I bought a hydraulic pressure measurement device from Bxpanded because I wanted to know. Inquiring mind, you know.

Thanks for all the good help. Once again, all of you are top notch.

I suspect the larger hose is not the same dash size as the other two. My guess is the two smaller hoses are -04 (1/4") and the larger hose is -06 (3/8"). Working pressure rating for single braid (R1) hose will be 2700 PSI. Double braid (R2 or R16) will be rated for 5400 PSI. DHH is not going to have anything as small as .490.. Your best bet is R17-04 which is 3000 PSI hose with an OD of .50 If you are really intent on going as small as possible Gates M3K is an R17-04 hose with an OD or .48". You will likely pay through the nose for that.

Dan

 

[PoTreeBoy]

I'm with TheOldHokie - somebody replaced a 1/4" hose with 3/8", and some were replaced with double-braid which is thicker and stiffer.
It's going to be hard to measure those hoses in place. If time is critical and somebody local can crimp fittings, you could buy hose and fittings to have on hand to have local shop cut and crimp (but they may not want to crimp non-purchased items).
I'm attaching the JIC thread size chart. The fitting thread is not always the same as the hose size.

 

[Tractor Gal]

Good info, TheOldHokie and PoTreeBoy. I did go to discounthydraulics to begin looking. There is an R-17 1/4" hose, rated at 3000psi...$1.68/ft. I'm not sure of the fittings but just looking at their diagrams, a 90 degree with female swivel is $8.68
and a male fitting on the other end $3 or something, makes the hose cost at somewhere around $22 which includes their fee to assemble. That's a far cry from $95...last I knew.

I'll keep looking. I may decide to replace that 0.67" OD hose just to give it a try. That may free up enough space to be worth it. I have to figure out which fittings. With PoTreeBoy's chart, I'll give it a whirl.

Thanks for all the help.

TG

 

[TheOldHokie]

Good info, TheOldHokie and PoTreeBoy. I did go to discounthydraulics to begin looking. There is an R-17 1/4" hose, rated at 3000psi...$1.68/ft. I'm not sure of the fittings but just looking at their diagrams, a 90 degree with female swivel is $8.68
and a male fitting on the other end $3 or something, makes the hose cost at somewhere around $22 which includes their fee to assemble. That's a far cry from $95...last I knew.

I'll keep looking. I may decide to replace that 0.67" OD hose just to give it a try. That may free up enough space to be worth it. I have to figure out which fittings. With PoTreeBoy's chart, I'll give it a whirl.

Thanks for all the help.

TG

DHH has good prices for custom hose assemblies but $22 would be for a 1 foot hose. A 4" hose is $28 + $15 shipping and tax so it winds up being closer to $45. The U type fittings you priced will be bubble crimps which have a larger diameter than a full shell crimp so make sure you have room to thread them through any openings and connected.

Dan