jcb 3d2 hydraclamps

[david c]

hello,wondering if someone can tell me what's wrong/what i'm doing wrong with hydraclamps.only use jcb occasionally but ever since i've had it i've been unable to get the backacter to move from the left where its stuck to the right.this wasn't a problem before but a bit of ditching recently suggested it would be a hell of alot handier if i could shift it.there is a small lever with a hinge in it which i've tried in both positions whilst pushing and pulling with the arm at 90 degrees to the machine.i've cleaned a fair bit of rust out of the rails the carriage slides on and greased it up and even had someone put a shackle and chain onto the hole for the pin that locks the slew and tried gently pulling with another machine whilst the backacter was used to take a little weight off the carriage but stopped as nothing was moving.all the hoses are fine and its not been welded or anything but no matter what you do no movement can be seen anywhere on the clamps.i would like to get this sorted hopefully without any massive strip down.someone told me that the clamps could be a bit of a problem.any pointers would be greatfully recieved.thanks.

[Mark.Rive]

Hi David, it is very likely the clamps are not releasing if the king post carriage has been left in the same place for years. Operate the lever as you described, then working any service on the excavator valve block should release the pressure in the clamps. You may need to lift the machine gently a fair few time to release if they are seized. Another option is to slacken the holding nut off and be a bit rough on them with the back-acter! although I personally am not a fan of this. But I have seen it done to very good effect!

Once you have freed them, you may find they leak when pressure is reapplied. Good luck. Mark

[tctractors]

Early Hydro Clap valves need pulling and pushing although they can rotate, so try pulling it up or pushing the control down.

[essexpete]

Just a thought, I assume that all the pipes to the clamps are in place and no one has manually over tightened or wedged the clamps?

[david c]

Thank you very much for the replies.Am going to have a good look at the thing later on today and make sure nothings been wedged/over tightened then as suggested get a bit heavy handed.Cheers David