BT600 backhoe swings right but not back left

[Tractor Gal]

Where would we be without some issues to solve about these tractors? It seems never ending...and I wouldn't mind if it would end!

My Kubota BX23 MLB was activated today, planning to use the backhoe. Everything is working as it should except the boom will not swing very well to the left. It goes right with no problems but will only VERY SLOWLY return back to the right. By slowly, I mean maybe 30 seconds. I hear no noises or bogging down when I try to return it left.

There is ample hydraulic oil and the hoses show no leaks. I've looked into the WSM and it indicates the valve spool, the relief valve, or the cylinder may have issues. Other things listed have checked out to be OK.

I had used the backhoe to dig a hole for a fence post holding a gate. It worked with no issues at all. That was about 2 weeks ago. I used the MMM for the grass also. Tractor has been in garage since then.

After seeing the problem, I took the two hoses for the swing cylinder off the control valve, started the tractor to see if there was fluid flowing. There was. I have not taken the hoses off the swing cylinder yet but thought that may be a good next step. I also thought about reversing the hoses to see if there may be some kind of restriction within that valve and back flowing may dislodge it. But, prior to doing either of those, I thought I would check in here to see if anyone has info. Maybe reversing the hoses would not be such a good idea?

Apparently, that relief valve can get stuck and can be cleaned. And, if it is stuck, would the rest of the backhoe continue to work? It seems odd to me that it would happen without warning but then again, how would I know. In looking at the diagram, it does not look particularly complicated to take that port relief valve apart but it would be good to know if that's a difficult process. There appears to be some small parts that would need to have good attention for re-assembly and/or losing!

The WSM does list as a potential problem...dust in overload relief valve. Solution says to flush hydraulic line. I think that's what I had done when I removed the hoses for that swing cylinder.

Any help and/or guidance would be greatly appreciated.

Tractor Gal

 

[Chanceywd]

Linkage from the handle to the valve loose?
Just an idea. I only have a BH77 on mine but have found the linkage on that loose in places with only a 100 hrs on it. Checked it again when i put it on a couple weeks ago.

Hope it is simple Tractor Gal

Bill

 

[Tractor Gal]

Linkage from the handle to the valve loose?
Just an idea. I only have a BH77 on mine but have found the linkage on that loose in places with only a 100 hrs on it. Checked it again when i put it on a couple weeks ago.

Hope it is simple Tractor Gal

Bill

I will check that but I don't think so. Yesterday, I noticed a sound I hadn't heard earlier. When I pushed the control stick to the left to swing the boom to the left, it had the same sound as when one of the cylinders has hit the max. For example, when the loader is curled, when it reaches max, the sound lets you know that as far as you can go.

Now the swing arm is not all the way to the left when this sound occurs so I wonder if this is the
indicator that the relief valve is stuck? I'll keep working on it.

Thank you, Chanceywd. Every idea is worth pursuing.
And, I do hope it is simple, too!

TG

 

[Kennyd4110]

Does it have one or two swing cylinders?

My gut feeling is a blown piston seal.

 

[Tractor Gal]

Does it have one or two swing cylinders?

My gut feeling is a blown piston seal.

Kennyd4110, There are two swing cylinders...one for each direction. I see no oil leak or anything else
unusual with that left cylinder. Would there be a visible indicator that a seal is blown or
anyway to test for that?

TB

 

[Kennyd4110]

If the piston seal is blown, there would generally be no visible leakage unless one side is vented (meaning the cylinder has only one hose).

 

[Tractor Gal]

If the piston seal is blown, there would generally be no visible leakage unless one side is vented (meaning the cylinder has only one hose).

Two hoses on the cylinder so that let's that out.

One correction: there is only only cylinder for the swing. Who knew? Apparently, I did not.

Tomorrow, I'm going to switch two sets of hoses. The set for the swing will go on the ports for the boom. The set for the boom will go on the ports for the swing. If I get the same result with the boom, that will indicate the problem
is in the control valve. I've looked at it a bit to see how hard it would be to work on it. So far, no conclusion but I'll see if the WSM has any info.

Thanks for the help, Kennyd4110.

TG

 

[Kennyd4110]

I still suspect the cylinder. It's possible the piston came off of the rod.

In the direction the swing "works", is the rod extending or retracting?

 

[Henro]

If the piston seal is blown, there would generally be no visible leakage unless one side is vented (meaning the cylinder has only one hose).

Two hoses on the cylinder so that let's that out.

Just a thought continuing Kennyd's point.

You could always extend or retract the cylinder fully, then take the hose of the end of the cylinder where the piston is, and then try to move the cylinder in the same direction. I imagine this would result in oil coming out of the cylinder at the fitting where the hose was removed, if piston seals are bad.

Never tried it, but think I will as I have a cylinder on my mini ex blade that has a possible piston seal issue, and I think doing this would either verify or eliminate the question.

Also not sure of the likelihood that a seal would fail in one direction, and work in the other...

 

[Kennyd4110]

Here is the process Henro is talking about:

 

[Tractor Gal]

I still suspect the cylinder. It's possible the piston came off of the rod.

In the direction the swing "works", is the rod extending or retracting?

As the swing moves to the right, the cylinder rod is extending.

I haven't gotten to the task of swapping the hoses of the swingt at the control valve with the hoses of the boom to see if it is the same result with the boom while the swing works. I'll get to it. Too hot right now!

I appreciate your input, Kennyd4110

TG

 

[Tractor Gal]

Just a thought continuing Kennyd's point.

You could always extend or retract the cylinder fully, then take the hose of the end of the cylinder where the piston is, and then try to move the cylinder in the same direction. I imagine this would result in oil coming out of the cylinder at the fitting where the hose was removed, if piston seals are bad.

Never tried it, but think I will as I have a cylinder on my mini ex blade that has a possible piston seal issue, and I think doing this would either verify or eliminate the question.

Also not sure of the likelihood that a seal would fail in one direction, and work in the other...

I'll give this a try. Hopefully, I can get the problem identified before
trying different repairs. I'm good at trying to fix the wrong thing!
But, I will have to wait until it's a little cooler.

TG

 

[Tractor Gal]

Here is the process Henro is talking about:

View attachment 82786

Thanks for the diagram. I'll certainly give this a try. Perhaps with all the help, I can pinpoint the problem. When I am able to do this, I will report the results. Thanks again.

TG

 

[Tractor Gal]

Thanks for the diagram. I'll certainly give this a try. Perhaps with all the help, I can pinpoint the problem. When I am able to do this, I will report the results. Thanks again.

TG

It's been quite a while since I had posted about this problem. Now, I'm back at it. This time, though, I am trying to removing the cylinder to take it for repair. One of the pins that holds the cylinder is stuck. At its location, there is not room to do much hammering or even get a punch tool in there from above since the platform of the backhoe is in the way. I put a hydraulic jack under the pin (the pin is vertical) and jacked the tractor up a bit, thinking the weight of the tractor may help. Didn't move even one bit. I put PB blaster on it several times and even left it overnight but no budge of the pin.

I've read that a 50/50 of atf/acetone is a good penetrant. Would there be any thing else to try?

 

[Henro]

It's been quite a while since I had posted about this problem. Now, I'm back at it. This time, though, I am trying to removing the cylinder to take it for repair. One of the pins that holds the cylinder is stuck. At its location, there is not room to do much hammering or even get a punch tool in there from above since the platform of the backhoe is in the way. I put a hydraulic jack under the pin (the pin is vertical) and jacked the tractor up a bit, thinking the weight of the tractor may help. Didn't move even one bit. I put PB blaster on it several times and even left it overnight but no budge of the pin.

I've read that a 50/50 of atf/acetone is a good penetrant. Would there be any thing else to try?

Can you get the pin out at the other end of the cylinder. I can't visualize what you have, but think if you could get the other end of the cylinder free, that would eliminate a question of the cylinder causing binding of the pin in question.

More than this I can't offer at the moment. Perhaps a picture would help some to give better advice...

 

[Tractor Gal]

Two yes's. I can easily get the other end of the pin out. And, yes, I thought a picture would be helpful. It's such a pain. Have to take the picture with the phone; download the picture to computer; then I can post here. But, to get such outstanding help, I need to put in a bit of effort. It's a little dark now so I'll try to get a picture in the morning.

The cause of the problem is simple. This is a 2004 tractor. I've had it 2 years. I've greased several times since I've had it but I never saw this grease zerk. Apparently, the prior owner(s) didn't either. Actually, I'd be surprised if the prior owners(s) greased it at all since their other maintenance was suspect. But, I digress.

I'm going to get some acetone on Monday to mix with the ATF. We'll see if that will do anything.

TG

 

[Tractor Gal]

OK, finally back at it. Here's a picture of the pin location...just behind the right rear tire with platform above making it difficult to hammer the pin down and difficult to hammer the pin up due to the reduced space.

I lowered the right stabilizer arm to lift the right side of the tractor, hoping the extra space would allow for a little more uummph while hammering. I also had gotten some acetone to mix a 50/50 mixture with transmission fluid. I had tried to get some around that pin several days ago to allow it to work but apparently it hasn't since the pin will not budge.

My next effort may involve trying to heat the metal that surrounds that pin, not to heat the pin itself. I've read a couple of things about that and how care must be taken. I suppose some orange spray pain would do the trick in the event that I bubble the paint.

Anyway, if there are other solutions, I'd be glad to give them a try if it's something that I can do. I had the same problem with the wheels on the mower that came with it. My neighbor had to use a sledge hammer and a lot of power to get those things out. if this is the same way, I think I'm out of luck.


I appreciate any comments/help. You're all good.

Tractor Gal

 

[tbk5]

Here is a pic of the swing frame off of Messicks. The is a bolt (030) that holds the pin in. Is it possible that the head sheared off on the side you are looking at but there is still enough on the other side to keep the pin from sliding out???

 

[Tractor Gal]

Here is a pic of the swing frame off of Messicks. The is a bolt (030) that holds the pin in. Is it possible that the head sheared off on the side you are looking at but there is still enough on the other side to keep the pin from sliding out???
View attachment 91891

Good thought, but no. I have removed the bolt.

 

[DustyRusty]

I had to remove a pin similar in size to that from an older snowplow this past weekend. I used a large flat-face punch, that was just slightly larger than the pin. It was stubborn, but I kept hitting it from one end and then the other. It only moved about a quarter of an inch in each direction, but eventually, it did come out. I suggest that you work it from both ends using a properly sized drift pin. I don't think that heat is going to do much for you.