FEL Drops When Lever Is Pulled To Raise

[bmarshall1]

HAPPY NEW YEARS!

Hello - New tractor owner here and first post. I have recently purchased a Cub Cadet EX3200 with about 140 hours - seemingly in pretty good condition. I am still in the learning process but have a conern.

The issue is when the tractor is cold and I am raising the FEL very slowly, the FEL will drop about 4 - 5 inches then stop, like a check valve closing. When the tractor is hot, the FEL will not catch and will continue to drop until I pull the lever to raise the FEL quickly.

On purchase the seller gave me a dealer receipt stating 'the FEL sometimes raised when trying to lower', the diagnosis and fix was to 'clean and connect fitting at valve block'.


I left the bucket about an inch off the ground last night and overnight it dropped to the ground, so does that mean there is a leak or bad seal?

Lastly, is there a way to bleed the lift cylinders, I did not see a bleed screw (do they need bleeding?).

Do any of these clues mean anything, is there any other info I can give to assist? Thanks in advance.

Bruce

 

[Peter 315]

You don't bleed the system it will do it when you operate the hyd cylinders , Cylinder leak or bleed down is common , How fast depends on the tractor there all different

 

[kennyd]

HAPPY NEW YEARS!

Hello - New tractor owner here and first post. I have recently purchased a Cub Cadet EX3200 with about 140 hours - seemingly in pretty good condition. I am still in the learning process but have a conern.

The issue is when the tractor is cold and I am raising the FEL very slowly, the FEL will drop about 4 - 5 inches then stop, like a check valve closing. When the tractor is hot, the FEL will not catch and will continue to drop until I pull the lever to raise the FEL quickly.

There are small check valves in the loader valve called "load checks" that are supposed to prevent that from happening. Not sure about parts availability on this generation Yanmar,, so this may not be a simple or inexpensive fix.

On purchase the seller gave me a dealer receipt stating 'the FEL sometimes raised when trying to lower', the diagnosis and fix was to 'clean and connect fitting at valve block'.

Another valve problem...


I left the bucket about an inch off the ground last night and overnight it dropped to the ground, so does that mean there is a leak or bad seal?

Lastly, is there a way to bleed the lift cylinders, I did not see a bleed screw (do they need bleeding?).

Sounds normal. Most FEL's drift down slowly, most manufactures even publish specs for allowable leakdown. There is no "bleeding" needed, these systems are self-bleeding and purge the aire through normal cycling on the loader.

Do any of these clues mean anything, is there any other info I can give to assist? Thanks in advance.

Bruce

Welcome to GTT. See my replies above in RED

 

[bigdeano]

HAPPY NEW YEARS!


The issue is when the tractor is cold and I am raising the FEL very slowly, the FEL will drop about 4 - 5 inches then stop, like a check valve closing. When the tractor is hot, the FEL will not catch and will continue to drop until I pull the lever to raise the FEL quickly.

Do any of these clues mean anything, is there any other info I can give to assist? Thanks in advance.

Bruce

It sounds like there may be a problem with a load check valve in your valve block. Maybe sticking open or dirt under it. Many loader valves have them to prevent the loader from going down when you start to lift the loader. On my Vickers valve they're right under the spool valves. If you have an exploded drawing of your valve it should show them if your valve has them.

That's my best guess anyway. Happy New Year!!

 

[PILOON]

I rather doubt if Cub Cadet incorporates check valves in their products.
As stated hydraulics self purge by nature of the system.
I suspect dirt or erosion in the valve with dirt being the most likely due to the low hours.
Another possibility is a bad fitting that allows air to enter but then under pressure there would be leakage at that location.
Most valve assemblies have a pressure release or regulator incorporated and a simple tad of dirt can cause it to leak and cause your symptoms.

 

[TMGT]

Second it sounds like a load check valve is not functioning properly. Not sure if you'll be able to do any service on it without taking the valve off and disassembling it.

 

[void777]

bmarshall1
Welcome to TBN

 

[RickB]

I rather doubt if Cub Cadet incorporates check valves in their products.

Load checks are a common feature of loader control valves. I’d be more surprised if this valve did not have them.

 

[npalen]

Would a load check allow lowering the boom if the engine was not running? Just asking as I don't remember having an FEL that wouldn't lower the boom with the engine off.
The loader on my Kubota drops very fast with a heavy load in the bucket.

 

[kennyd]

Would a load check allow lowering the boom if the engine was not running? Just asking as I don't remember having an FEL that wouldn't lower the boom with the engine off.
The loader on my Kubota drops very fast with a heavy load in the bucket.

Yes. You are confusing “load check” with a regular check valve or restrictor, not the same thing.

 

[npalen]

To clarify what I mean by "The loader on my kubota drops very fast.....", it is difficult to lower a heavy load a small amount by barely cracking the valve without "bouncing" the load.
How does a load check act differently from a pilot operated check valve? Is it like a tapered land on the valve spool that smooths the transition?

Edit: This link may help the OP troubleshoot:
Prince Manufacturing Corporation > Support > Loader Valve FAQ

Edit #2: This video explains the load check to a point but it shows a check valve that would need to be overcome in order to lower the load. Maybe I missed something as the accent is a bit difficult for me to understand.
how does a load check on a loader valve work? - Yahoo Video Search Results

 

[kennyd]

To clarify what I mean by "The loader on my kubota drops very fast.....", it is difficult to lower a heavy load a small amount by barely cracking the valve without "bouncing" the load.
How does a load check act differently from a pilot operated check valve? Is it like a tapered land on the valve spool that smooths the transition?

Edit: This link may help the OP troubleshoot:
Prince Manufacturing Corporation > Support > Loader Valve FAQ

With all due srespect, your questions would be better asked in a separate thread, the DPOCV discussion will not help the OP.

 

[LD1]

I agree with what others have said that you probably have a sticking load check in your valve body

 

[bmarshall1]

Hello All - Thanks or the replies. Sounds like the Load Check Valve may be the culprit; is this a user serviceable part? I am very good at mechanics and have replaced engines before so I am not afraid to get my hands dirty.

From the comments it seems like I will need to remove the valve body and the check valve is underneath? Once I have it out is there anything else I should R and R while it is out?

 

[kennyd]

BMarshall,
You might want to see if you can purchase the Technical Manual for your machine, or at least see if a dealer can give you some parts breakdowns before you start turning wrenches.

 

[LD1]

The load check is an integral part of the valve....mut still removable. Usually under a cap or plug.

It "can" probably be removed without removing the valve assembly. But you need to keep things as clean as if you were rebuilding an engine or transmission.

It's probably just a bit of foreign contaminate caught in the seat of the load check preventing it from sealing.

So what I would do, would be disassemble and.clean clean clean. Then inspect all mating surfaces. If all is well, put back together and get it

 

[ADSNY]

Load Check Valves are aka Counterbalance Valves. That might help in your search for an answer.

 

[oldnslo]

In this that is not a correct statement.

A valve load check is actually a check valve built into the direction control valve to prevent oil from flowing from work ports to the pressure port.

Counterbalance valves are also used to prevent loads from falling but they include the free flow check and pilot operated relief valve in one valve assembly.

Agree similar functions but not the same application

 

[npalen]

So would a load check normally hold the load in a raised position assuming there was no cylinder piston seal leakage and require the pump to produce pressure in the rod side of the lift cylinders to lower the load?

 

[LD1]

So would a load check normally hold the load in a raised position assuming there was no cylinder piston seal leakage and require the pump to produce pressure in the rod side of the lift cylinders to lower the load?

Cylinder Piston seals would NOT cause a loader to not hold the load anyway.

IE:. Lift cylinders......and their Piston seals......will not cause loader to drift