Backhoe problem

[2515R Dude]

Need advise,
Yesterday my backhoe started acting up.
If i take the boom all the way to one side and then start turning it back, it goes 1/3 of the way, then stops for a second, then keeps going another 1/3, then hesitates again, then goes all the way to the end.
Pretty much same thing with the boom curl, when i extent it all the way out and start the curl, it stops in the middle, then keeps going. Same with the back movement when i try to extend it.

The oil is on MAX, clean as teardrop, so no problem there.

I called the dealer, he said he had never had such an issue. He also called TYM. They also scratch their heads.

The tractor is 2022 Branson 2515R with only 190 Hours.

Any thoughts?

 

[K5lwq]

My first question is how is it plumbed? Off of the rear remotes or does it have it’s own dedicated lines?

 

[2515R Dude]

I dont know the difference, it is a line which i make a loop when the backhoe is not connected. It comes from the rear of the gear box. I guess it is a dedicated line but not sure.

 

[ROUSTABOUT]

I dont know the difference, it is a line which i make a loop when the backhoe is not connected. It comes from the rear of the gear box. I guess it is a dedicated line but not sure.

You are plumbed off tractor hydraulics. Ours has a separate pump that goes on PTO. That's what he was asking.

 

[K5lwq]

Okay if you have to use a loop when the backhoe is disconnected then it is plumbed using power beyond line likely from the loader valve.

Do you see the same issue with the loader? If not, I would look closely at the quick connects that feed the backhoe. Disconnect and reconnect each one to make sure a solid connection. Also, is this the first time using the backhoe or is this a new issue and it has worked correctly in the past?

 

[Hoss710]

the big industrial units have shocks built into the cylinders as to not bang on full swing. but I doubt a tractor backhoe would have the same features.

 

[Willman]

My Bradco BH has an in line filter ON the BH, could yours have one and clogged?

 

[rScotty]

Okay if you have to use a loop when the backhoe is disconnected then it is plumbed using power beyond line likely from the loader valve.

Do you see the same issue with the loader? If not, I would look closely at the quick connects that feed the backhoe. Disconnect and reconnect each one to make sure a solid connection. Also, is this the first time using the backhoe or is this a new issue and it has worked correctly in the past?

That would be my guess too. If it worked before, it is something simple in the hydraulic feed. Either the quick connects as you say, or something bumped the rear remote control levers located beside the seat and the levers aren't opening the remote valve fully.

 

[2515R Dude]

Okay if you have to use a loop when the backhoe is disconnected then it is plumbed using power beyond line likely from the loader valve.

Do you see the same issue with the loader? If not, I would look closely at the quick connects that feed the backhoe. Disconnect and reconnect each one to make sure a solid connection. Also, is this the first time using the backhoe or is this a new issue and it has worked correctly in the past?

I attached the picture how the BH connected to the tractor.
I don't see any problem with the loader. it works smooth.
The dealer told me to connect and reconnect the CCs, no love here, same issue. The connection is solid, no leaks.
Also, i don't see any additional filters besides the one for the hydraulics. It was changed 90 hour ago on 100 hours service.
This BH is used for more than 50 hours, and it started acting up yesterday after flowless 1 hour work.
There are some changes today morning, instead of stopping every 1/3 of the way, it starts fast then start jumping 5-7 times while going this half circle.

 

[rScotty]

OK. So it's time to start eliminating things.
BTW, that feed and return to the hoe looks like a homebrew hydraulic extention rather than factory remotes. Is that so? And if so, then the BH probably gets it's feed from the power beyond port - labeled PB - on the loader control valve. And so one of those hoses you have pictured is from the PB port - probably the smaller one to the left - and the other is the return back to the tractor transmission/hydraulic sump.

By the way, are you sure you don't have those hoses reversed? Do the fittings make that impossible?

It's not the hydraulic pump because the loader works well. That's great.
And It probably isn't the power beyond port up on the loader valve because that is just a port and a hose.

An important piece of info is whatever is going on affects all the BH functions. That means it isn't an air bubble in a cylinder or a bad backhoe control valve.

So that leaves either reversed hoses, some blockage on one of the lines, a relief valve n the backhoe control valve gone bad, or the hose connections.

Check the hoses for reversed first. Darn, I wish I was there with my pressure gauge.

Nest gently tap on the pressure relief valve or feel of it to see if it is jumping. The relief valve is usually the longest cylinder jutting out from the control valve block. Sometimes there are several. A relief valve It is just a pressure spring and poppet valve. Sometimes you can hear it operate. In normal operation the pressure relief doesn't do anything. If that valve is cycling as the hesitation happens then that is the problem. It should be quiet.

BTW, does the engine load down when the hesitation happens or does it speed up? Any noises?
rScotty

 

[2515R Dude]

OK. So it's time to start eliminating things.
BTW, that feed and return to the hoe looks like a homebrew hydraulic extention rather than factory remotes.

It was installed by the dealer when i purchased the tractor+BH

By the way, are you sure you don't have those hoses reversed? Do the fittings make that impossible?

They are different, no way to reverse, only one way to connect, besides, it worked this way before.
I attached the pictures of them

An important piece of info is whatever is going on affects all the BH functions. That means it isn't an air bubble in a cylinder or a bad backhoe control valve.

So far for me it looks like it does affect all the functions, the turn and the curl of the boom are affected for sure.

Check the hoses for reversed first. Darn, I wish I was there with my pressure gauge.

Checked, they are not, and yes, i wish too. You would make a lot of money here because of the complete lack of tractor mechanics.

Nest gently tap on the pressure relief valve or feel of it to see if it is jumping. The relief valve is usually the longest cylinder jutting out from the control valve block. Sometimes there are several. A relief valve It is just a pressure spring and poppet valve. Sometimes you can hear it operate. In normal operation the pressure relief doesn't do anything. If that valve is cycling as the hesitation happens then that is the problem. It should be quiet.

BTW, does the engine load down when the hesitation happens or does it speed up? Any noises?
rScotty

The engine does not change it's RPMs, no audible changes that i can hear, and no noises coming from underneath the panel with the joysticks. I'll try to disassemble the cover panel and tap on them, but if it is a relief valve, shouldn't it be a constant thing, not jumping?

The dealer is suggesting to change the connectors. What do you think? In my limited knowledge and understanding, the connector ether works or not.

Thanks

 

[rScotty]

SNIP

The engine does not change it's RPMs, no audible changes that i can hear, and no noises coming from underneath the panel with the joysticks. I'll try to disassemble the cover panel and tap on them, but if it is a relive valve, shouldn't it be a constant thing, not jumping?

The dealer is suggesting to change the connectors. What do you think? in my limited knowledge, and understanding the connector ether works or not.

Thanks

Well, something should be changing with the engine. Maybe put a load on the backhoe and run the engine very slow.

Yes, a relief valve could be a constant thing....but they never are. The reason they aren not slow and constant is because fairly big orfice and open quickly to drop dangerous pressures fast.
So much so that it is common for them to dump the pressure, close, and have to reopen again a fraction of a second later. So they tend to make a high speed stuttering sound. Sometimes it happens so fast that what you hear sounds like a single shriek - it all depends on the orfice & spring size. Basically the same sound you hear when you crank the steering over to full lock on the family sedan.

But one thing is for sure, if you can put your hand on it you will feel the vibration as it oscillates. In five or ten seconds of relief that valve will get noticibly hotter too.

Yes, I like that dealer's suggestion. It certainly could be the connector internals. That's a good hint from him - and maybe he has seen it before. The thing that keeps the connector from leaking is just a ball valve with a spring and either of those can go bad. Mostly it is a corroded. Not often, but the cheaper quick connectors do have more problems than the expensive ones. And one with a loose ball or cracked spring could surely do just exactly what you are describing.

I'd swap them all. Cheaper than a mechanic call.

OH. I see in the photos that those connectors look to be standard aftermarket with standard thread. DO NOT use common plumbing fittings. It's just too dangerous. Please use hydraulic pressure rated parts. Any rural or tractor supply store should have them.
luck.
rScotty

 

[2515R Dude]

Well, something should be changing with the engine. Maybe put a load on the backhoe and run the engine very slow.

I put a load, noting changed as i could notice, no noise level, no RPM. The only difference was that it started running a little smother because of the increased inertia, it does not stop as abruptly as the empty one. Ran it 1K, 1.5 and 1.8RPM

So they tend to make a high speed stuttering sound. Sometimes it happens so fast that what you hear sounds like a single shriek - it all depends on the orfice & spring size. Basically the same sound you hear when you crank the steering over to full lock on the family sedan.

But one thing is for sure, if you can put your hand on it you will feel the vibration as it oscillates. In five or ten seconds of relief that valve will get noticibly hotter too.

I opened the panel and tried to listen, and put my hand on two things which i thought are the relief valves. #1 and #2 on the attached picture see below. No noise, no vibration. The only thing the #1 got a little warmer after my 5-10 swinging the boom.
The #2 had no changes.
BTW, which one is the relief, the #1 or #2?

Yes, I like that dealer's suggestion. It certainly could be the connector internals. That's a good hint from him - and maybe he has seen it before. The thing that keeps the connector from leaking is just a ball valve with a spring and either of those can go bad. Mostly it is a corroded. Not often, but the cheaper quick connectors do have more problems than the expensive ones. And one with a loose ball or cracked spring could surely do just exactly what you are describing.

He says he never had such an issue and this suggestion came from TYM.
Also, what supports the idea of the connectors, the problem started with 2 stops per swing every 1/3 of the way. After i disconnected and connected the BH it changed its behavior and now it makes 5-7 stops.
I checked the connectors inside, they look like new, no dirt, no rust no anything else.
Hopefully tomorrow i'll be able to get new connectors and install them

OH. I see in the photos that those connectors look to be standard aftermarket with standard thread. DO NOT use common plumbing fittings. It's just too dangerous. Please use hydraulic pressure rated parts. Any rural or tractor supply store should have them.
luck.
rScotty

Are you saying that that those ones are not good connectors? Which ones should i buy and how can i see the difference between the good ones and bad ones?

Also, i took a picture of the connection where the hose is connected. I guess it is PB point?

 

[oldnslo]

I am late to the party but does this happen with tractor at idle vs higher RPMs? Reason for asking is that sometimes the QD will be fine at lower flow but fail at higher flows.

 

[ptsg]

I put a load, noting changed as i could notice, no noise level, no RPM. The only difference was that it started running a little smother because of the increased inertia, it does not stop as abruptly as the empty one. Ran it 1K, 1.5 and 1.8RPM

I opened the panel and tried to listen, and put my hand on two things which i thought are the relief valves. #1 and #2 on the attached picture see below. No noise, no vibration. The only thing the #1 got a little warmer after my 5-10 swinging the boom.
The #2 had no changes.
BTW, which one is the relief, the #1 or #2?

He says he never had such an issue and this suggestion came from TYM.
Also, what supports the idea of the connectors, the problem started with 2 stops per swing every 1/3 of the way. After i disconnected and connected the BH it changed its behavior and now it makes 5-7 stops.
I checked the connectors inside, they look like new, no dirt, no rust no anything else.
Hopefully tomorrow i'll be able to get new connectors and install them


Are you saying that that those ones are not good connectors? Which ones should i buy and how can i see the difference between the good ones and bad ones?

Also, i took a picture of the connection where the hose is connected. I guess it is PB point?

On the first picture, the #1 is a check valve that prevents you from running the BH if you accidentally swapped the hoses and fed pressure via the Tank port on the BH control valve.

#2 is the main relief valve for the control valve of the BH.

On the second picture, the line where the arrow is pointing is indeed the PB line that will feed the BH.

 

[2515R Dude]

I am late to the party but does this happen with tractor at idle vs higher RPMs? Reason for asking is that sometimes the QD will be fine at lower flow but fail at higher flows.

Any rpm

 

[2515R Dude]

On the first picture, the #1 is a check valve that prevents you from running the BH if you accidentally swapped the hoses and fed pressure via the Tank port on the BH control valve.

#2 is the main relief valve for the control valve of the BH.

On the second picture, the line where the arrow is pointing is indeed the PB line that will feed the BH.

Interesting, meaning there is something wrong with the check valve because it got warmer. In my understanding, if it's función only to prevent backward connection, it should not work at all - get warmer ?

 

[ptsg]

Interesting, meaning there is something wrong with the check valve because it got warmer. In my understanding, if it's función only to prevent backward connection, it should not work at all - get warmer ?

It should get at least the same temperature as the hydraulic fluid gets, probably slightly higher since it may cause a slight restriction there.

Even if it was bad, it wouldn't really affect much on the BH unless the hoses were connected backwards, but you already said it's not even possible.

 

[2515R Dude]

OK, so my understanding was wrong. So, what is left? Connectors?

 

[K5lwq]

I support the connector plan. One thing that concerns me is that if I understand correctly you are only seeing the pause in one direction of movement and not the other. I understand on multiple functions but only one way. Is that correct? If so that leads me to suspect the valve itself as a problem.

That is a stack type valve so there could be an issue with where the spool valves mate together. Or if it is only on the two functions, swing and boom curl then maybe you could swap spool valves to test. But that would be a process and somewhat time consuming.

So you don’t see the symptoms when curling the bucket?