Need help with my rear remotes

[JPVV]

Hi,

I have a 2008 Kubota L3940 and I have been having an issue with my rear remote and I don't know where to start. I was hoping someone out there could get me started to figure things out. I have attached pictures of my set up - I believe it was installed by Kubota dealer.

The problem is only one of the connections work. I have a hydraulic top link and it only works in one direction. When I switch the hose connection, it only works in the other direction (in or out). When I push my lever to activate the connection that doesn't work, it makes a loud squealing sound. I don't know where to start troubleshooting this system (and how to do it safely) . Any help in that direction would be much appreciated!

Thanks!

 

[CobyRupert]

I'd say we know the problem is NOT the toplink's cylinder, hoses or connectors, because it works when hoses are swapped.
I'd also say it's not one of the tractors connector's, because both connectors have to flow oil even when cylinder is only being operated in one direction (i.e. oil fills one side of cylinder, and is returned from the other side when cylinder moves).

If you follow the handle in your 3rd picture, to the source of the hydraulic lines that supply the remote connectors shown in your 2nd picture, that is where you should find the actual Selective Control Valve (SCV). I'm no expert, but I'd guess that's where the problem is.

When you push the lever and get the squeal, can you see if the top links hydraulic hoses are pressurized (do they move)?
I'd guess they do, but something wrong in the SCV isn't allowing the return line side of the cylinder to empty, so cylinder can't move, so the system's relief valve operates and you hear the squealing.

This is just a guess. Hopefully more experienced people chime in.

 

[CobyRupert]

I wonder if running SCV's in a "continuous flow mode" (example when you bungee cord the handle so you can operate a woodsplitter) , overheats a SCV?

 

[LouNY]

One possibility is that one connector is not getting fully connected.
If the center plug on the tractor side is not fully locked out it could possibly allow return flow,
but not supply flow.
When you connect your remote hoses;
are you pushing the hose end in and is the tractor connector moving forward then back a bit?
are both of the tractor halves going forward when you connect your hoses?
when you disconnect your hoses are you just pulling on them, do they both take the same effort to pull free.
do your tractor halves move back and forth freely and evenly?

 

[JPVV]

I wonder if running SCV's in a "continuous flow mode" (example when you bungee cord the handle so you can operate a woodsplitter) , overheats a SCV?

I bought this tractor this past April and the rear remotes were already acting up and as far as I know the only thing ever attached to the rear remote with previous owner was the hydraulic top link.

I do run in "continuous flow mode" with my log splitter - before I did this, I called the kubota dealer and asked if this would be a problem (and they said it was fine to use like this) and also did research online - seems that other folks use it like this and haven't had any issues (at least that I could find)....

 

[JPVV]

One possibility is that one connector is not getting fully connected.
If the center plug on the tractor side is not fully locked out it could possibly allow return flow,
but not supply flow.
When you connect your remote hoses;
are you pushing the hose end in and is the tractor connector moving forward then back a bit?
are both of the tractor halves going forward when you connect your hoses?
when you disconnect your hoses are you just pulling on them, do they both take the same effort to pull free.
do your tractor halves move back and forth freely and evenly?

When I first bought this tractor back in April, it had the hydraulic top link attached. It worked, but didn't work great in one direction - it would often make the squeal noise when engaged in one direction, I would put the lever back to neutral, and then when I activated the lever again, it would creep very very slowly. Eventually, it
stopped creeping...

I will go and connect top link tomorrow and answer these questions. Generally, I would say both sides seem to be the same when connecting, but I have noticed that sometimes one will be harder to disconnect at times...

What do you mean by "do your tractor halves move back and forth freely and evenly"? I don't understand the "back and forth" part of that question.

Thanks everyone for their help and input!

 

[JPVV]

When you push the lever and get the squeal, can you see if the top links hydraulic hoses are pressurized (do they move)?
I'd guess they do, but something wrong in the SCV isn't allowing the return line side of the cylinder to empty, so cylinder can't move, so the system's relief valve operates and you hear the squealing. .

Yes, I think the hoses move when I get the squeal. I will confirm tomorrow... Thanks!

 

[LouNY]

When you mate the female ends, the cylinder hose ends to the tractor females.
Do you just push them in till they connect and then give them a light pull to be sure they latched in?
When you disconnect do you just pull the hoes out of the female tractor ends?
Do they require a sharp tug to disconnect?
If you grab the lines going to the tractor connectors can you move those back and forth almost a 1/4 of an inch each way?
Have you tried flushing the bodies with WD-40 or a similar product while moving the tractor ends back and forth?
There are o-rings on them that can become dislodged and not allow the connectors to latch in fully.

 

[JPVV]

When you mate the female ends, the cylinder hose ends to the tractor females.
Do you just push them in till they connect and then give them a light pull to be sure they latched in? Yes, they both seem to act the same
When you disconnect do you just pull the hoes out of the female tractor ends?Yes
Do they require a sharp tug to disconnect?Yes, they require a sharp tug - both seem the same in this respect as well
If you grab the lines going to the tractor connectors can you move those back and forth almost a 1/4 of an inch each way?Yes, between 1/8' and 1/4"
Have you tried flushing the bodies with WD-40 or a similar product while moving the tractor ends back and forth? No - I don't have any WD-40 on hand, I will try this soon
There are o-rings on them that can become dislodged and not allow the connectors to latch in fully.

I answered the above questions in the quote - hopefully in bold

I went over to my shop this morning to see about the questions above...it has been a while since I hooked up the top link - when it was acting erratically in the spring, I just put the old one on and hadn't tried it since.

When I hooked it up today, it would exhibit basically the same issue as it had in spring - it would act erratically - sometimes it would work, sometimes it would work really really slow, and sometimes it wouldn't work at all in the one "bad" direction (depending on which hose is hooked to which connector). Even if it worked, it would make a squeal noise in that direction. Not sure what to think about that...

I will try to flush out with WD-40. Any other ideas where to go from here? Thanks!

 

[Gordon Gould]

Is that top link the only thing you have to put on the rear remotes ? If you had or could borrow a different cylinder you could confirm that the tractor has a problem or not. The top link could be the problem especially if it is the type that has dual pilot operated check valves. Maybe you could test the top link on a friends tractor. Just a thought.

Edit: Your top link is probably OK since you can swap ends to push it both ways but something weird and it would be nice to rule some things out.

gg