BT600 backhoe swings right but not back left

[GreensvilleJay]

OK, stared at this and it occours to me that IF the the plate labelled 'D' ,somehow got off center, then the spool 'B' would not be able to go down. That might happen if bolts 'L' got a wee bit loose and both 'K' and 'D' moved. Plate 'D' looks like 'I', to me and the spool does go through 'I'
Before you soend a LOT of time removing the entire 'valve block/ assembly', carefully remove the bolts 'L' and slide off the 'K' and whatever else. I'm thinking the spool has to be in the down position as all that stuff gets assembled and the bolts get tightened. Wondering if anyone has tore them apart, if there's info in the WSM other than 'replace entire unit' ???

 

[TheOldHokie]

View attachment 92502

OK, stared at this and it occours to me that IF the the plate labelled 'D' ,somehow got off center, then the spool 'B' would not be able to go down. That might happen if bolts 'L' got a wee bit loose and both 'K' and 'D' moved. Plate 'D' looks like 'I', to me and the spool does go through 'I'
Before you soend a LOT of time removing the entire 'valve block/ assembly', carefully remove the bolts 'L' and slide off the 'K' and whatever else. I'm thinking the spool has to be in the down position as all that stuff gets assembled and the bolts get tightened. Wondering if anyone has tore them apart, if there's info in the WSM other than 'replace entire unit' ???

Plate D is not going to get off center and yes I have taken sections apart. For a simple 4 way, 3 position, spring center section its pretty simple. If there is room to access the end cap removing it would not be a bad idea. All of the other bits are held in place by screw G.

Dan

 

[Tractor Gal]

Have you verified the spool will not move inward? If so that section is going to have to come off for service.

If ther is room to get it off the end without removing the entire assembly from the framec I would reccomend that approach. Its just a spring center valve and nothing scary inside that end cap. Once you have it on the bench the rest should be pretty straight forward. Hopefully its something simple like a broken spring.

Dan

When the spool is depressed with the joystick, it does not depress. That's the only verification but it seems that would be enough. The spool lifts but will not depress.

In looking at the control valve assembly, it is difficult to see how the whole thing fits together. It appears that there are o-rings between sections but I don't fully see how all those valves are held together. I'm continuing to research. Taking off the one section for the swing valve would be perfect. As you say, it is on the end which is certainly helpful. But, again, I have to mull things over and over before I do anything. Besides, it's going to be in the teens soon and that's a bit nippy to work at this.

Thanks for the help, TOH. Any continued info would be helpful.

TG

 

[PoTreeBoy]

Have you verified the spool will not move inward? If so that section is going to have to come off for service.

If ther is room to get it off the end without removing the entire assembly from the framec I would reccomend that approach. Its just a spring center valve and nothing scary inside that end cap. Once you have it on the bench the rest should be pretty straight forward. Hopefully its something simple like a broken spring.

Dan

I'm not too sure about separating it on the backhoe. It would be really hard to get those o-rings back in place to reassemble it. If she could remove the end cap on that section in place, I agree with you, that's a low risk and might reveal an issue.

 

[TheOldHokie]

The valve is a typical sectional valve stack and is held together by three tie rods and six hex nuts. The tie rods go cross wise through each spool in the stack like a shish kebab. The swing spool is on the end making it the easiest to access. Looking at the parts diagrams it appears the stack is bolted to a panel on the frame of the hoe with two hex screws that go into the bottom of one of the end covers.

Dan

 

[Tractor Gal]

In looking at the exploded view of the entire control panel, it appears that the swing valve (#140) is nearest to the head of the bolt instead of at the bolt end. This would make it hard to remove just the swing valve, I would think. Am I seeing this correctly? Here's the exploded view:

 

[TheOldHokie]

I'm not too sure about separating it on the backhoe. It would be really hard to get those o-rings back in place to reassemble it. If she could remove the end cap on that section in place, I agree with you, that's a low risk and might reveal an issue.

I have no experience with that particular valve but I have probably assembled and disassembled this stack on the tractor dozens of times and the orings are no problem whatsoever. As long as you have room to pull the sections clear of the tie rods its a piece of cake. in the case of the BT600 it looks like the panle the valve is mounted to wraps around the valve so it may not be possible.

Dan

 

[TheOldHokie]

In looking at the exploded view of the entire control panel, it appears that the swing valve (#140) is nearest to the head of the bolt instead of at the bolt end. This would make it hard to remove just the swing valve, I would think. Am I seeing this correctly? Here's the exploded view:

View attachment 92507

There are no bolts - they are double ended studs (tie rods) with hex nuts on both ends. Assuming there is clearance the valve can be disassembled from either end. How much room is there between the end of the valve and that panel its bolted to?

Dan

 

[GreensvilleJay]

Q for TOH

hmm, what happens if that bolt G is no longer screwed into the spool B ?
If it wasn't screwed in, would you be able to pull the spool out the top ?
Without having a valve in hand, it's hard to fathom WHAT is preventing the spool from being depressed down !

 

[TheOldHokie]

Q for TOH

hmm, what happens if that bolt G is no longer screwed into the spool B ?
If it wasn't screwed in, would you be able to pull the spool out the top ?
Without having a valve in hand, it's hard to fathom WHAT is preventing the spool from being depressed down !

The spool is retained in the valve body by the spring, guide bushings and bolt G. The spring is compressed whenever the spool is shifted in either direction and is what returns it to the mid-point.

Remove bolt G and the springs and guide bushings can be removed from the end of the spool and the spool can be withdrawn from the top.

Anything lodged between the end of the spool or bolt G and the end cover could prevent the spool from moving inward while still allowing it to move outward. End clearance is probabl in the neighborhood of 3/16". Also any sort of debris lodged in one of the glands could prevent the spool from moving in just one direction.

I am inclined to thing the former rather than the latter.

I would slso like to have a more robust determination that the spool is the culprit and not the linkage. Removing the joystick, base plate. and linkage would mske that possible. It will have to come off in any event.

Dan

 

[#40Fan]

If you start watching around 16:00 mark, you'll get a good idea on what you'd need to do to remove the valve.

 

[Henro]

If you start watching around 16:00 mark, you'll get a good idea on what you'd need to do to remove the valve.

This video should be a GREAT help to TG.

Thanks for posting. Should give her a good idea what is involved. Naturally she is not adding anything, but removal and replacement of what is there now would be exactly the same procedure basically.

 

[TheOldHokie]

If you start watching around 16:00 mark, you'll get a good idea on what you'd need to do to remove the valve.

Excellent!!!

Dan

 

[Tractor Gal]

You are right, TOH. In looking at the backhoe earlier today, the whole control valve needs to be removed since there is not room to remove the bolts that hold all the valves together. I continue to contemplate.

TG

 

[TheOldHokie]

You are right, TOH. In looking at the backhoe earlier today, the whole control valve needs to be removed since there is not room to remove the bolts that hold all the valves together. I continue to contemplate.

TG

Careful - dont misquote me. You do not need to remove the bolts. You simply need to be able to remove the nuts and slip the sections off the end one by one. Thats probably about 1.5" of clearance. If you watch the video you will see the tie rods can also be shifted alll the way to one end to gain clearance on the other end.

If you can remove the pedestle as shown in the video its a piece of cake.

Dan

 

[Tractor Gal]

Excellent!!!

Dan

OK, I see how that works. I'll have to look at the "tower" on this BX23. I'm not certain it can be removed as this guy has done with his tower. If it could be removed, it would be a lot easier...I would think. Then, I could remove the swing valve, bring it inside onto a flat surface and disassemble.

Even if I have to remove the entire control valve, I can either get some threaded rod of the same dimension to insert into the remaining valves of the bank to hold them together while I work on the faulty one...if it is faulty. I doubt that the current bolt is threaded enough to allow that, but I'll look at the exploded diagram again. I'm going to try to rotate the spool first to see if there is debris in there that can be dislodged.

All good info. Learning is a wonderful thing!

TG

 

[GreensvilleJay]

looks like 5 (?) bolts and washers (#100,110) hold the 'Step' assembly on. Will also need to remove 2 cover plates, #s190 + 240. Once removed, should have easy access .

 

[ruger1980]

Rather than take the entire valve body out I would remove the cap on the bottom of the section and inspect the spring and the capture bolt. I have seen the bolt back out on valves before and limit movement of the spool. if with the cap off the spool still does not able to be moved then remove the lines and fittings in the swing section and inspect for debris in the spool.

No sense making more work for yourself than need be,

 

[GreensvilleJay]

this....
I have seen the bolt back out on valves before and limit movement of the spool.

is my 'hunch'.
it could even be totally out of the spool,allows upward movement but stops going down.
Removing the two 'L' bolts and seeing what's going on should be kinda easy.

 

[TheOldHokie]

this....
I have seen the bolt back out on valves before and limit movement of the spool.

is my 'hunch'.
it could even be totally out of the spool,allows upward movement but stops going down.
Removing the two 'L' bolts and seeing what's going on should be kinda easy.

The issue is access. Go back and look at the video around the 17 minute mark where he removes the front cover over the valve. Good luck getting in past those hoses to access the screws on the end cover. There are 12 hoses in two layers and spaced about 1" on center.

Dan