Lemac Quick Coupler not disengaging

[hen56]

I recently purchased a hyundai r80cr-9 with an aftermarket Lemac quick coupler, havent worked with one before. But the coupler will not disengage the bucket. I have 12V and audible buzzer at the switch when pressed, and 12V at the coupler valve regulator but the hydraulic ram isn't moving in at the bucket. No audible change from the pump either when pressed. Could the valve regulator be at fault and is there a way to test it? Should there also be solenoids or relays to check too? Thanks

 

[Tags]

Welcome to HEF!

Are you curling the bucket all the way in and bottoming out the bucket cylinder when the button is pushed? If not, give that a shot.

 

[TSalmon]

I have a Tefra quick coupler and like Tags mentioned after i release the switch in the cab I have to fully curl my stick and bucket and hold the bucket curl for 5 seconds.

 

[hen56]

Thanks for the replies, yes I've tried fully uncurling, pressing switch and curling all the way in holding the hydraulic pressure on the bucket but no movement in the QC ram. I noticed the ram is dusty/dirty suggesting it hasn't been used in quite a while! Should applying pressure on the curl in be enough for force the QC ram to retract? If I'm right, pressing the switch should release the force holding the QC ram open?

 

[92U 3406]

It all depends on the pressure if its attached to the curl circuit. You might have to run the function over relief to get it to do anything.

 

[Tags]

It could also be a wiring issue or a solenoid not operating issue. May need to try to trace the wires from the boom to wherever they go and make sure they are not crushed or severed. May also need to trace the wires from the cab switch as well.

 

[hen56]

Thanks for the replies. Quick update on the issue. I replaced the solenoid plug as it was cheap and to rule it out as faulty, but the new plug has an LED which isn't lighting up when the switch is pressed. I'm measuring 11.90V at the plug terminals between switch wire and earth. Does it have to be more than 12V for the QC valve block to work?

The battery isnt the best but i dont want to replace it yet if its not going to fix the issue, it has 12.5V across the terminals with the engine running.

Also, when curling the bucket in I've noticed that the pipe at the top of the QC valve block pressurises when fully curled. I haven't traced the pipes yet under the cab but I assume this pipe is coming from the bucket ram. Neither of the pipes attached to the QC visibly pressurise when attempting to disengage, so the valve block mustn't be opening for oil flow.

I suppose my question is, if the voltage isn't the issue, could the valve block be faulty if it isn't opening with the switch pressed? I dont think the LED on the solenoid plug should illuminate when it's not plugged in as the positive and negative terminals don't seem to be connected in the plug itself, rather when the circuit is completed when plugged in to the block.

I could run a direct wire from battery + and see if I get above 12V at the terminal plug to rule this out.

Any advice appreciated!

 

[Kobe Steel]

try checking the coils resistance with a multimeter, should be around 4-5 ohms I think. You can take a screw driver or Allen key and touch it to the end of the coil when it is powered on and see if it becomes magnetic. The cartridge may have a push pin that you can press in to manually override if the coil is not working.

 

[hen56]

Hi all, the problem has been solved! Whoever owned the machine before me had wired the negative onto the earth terminal of the solenoid plug instead of the negative terminal...

When replacing the plug I copied the original wiring, as technically it is an earth wire to the chassis, but when researching how solenoid valves work I changed the wire over to the negative end and hey presto, it works like a charm. Thanks for everyone's input, I'm not even angry at previous owner, just glad it was such an easy fix