jcb 3cx grey cab auxiliary hydraulics

[knighty]

1990 JCB 3CX grey cab

no auxiliary hydraulcs on the back... I'm going to have a load of tough old concreat to break up

I was going to get a pecker for my 1.5ton digger... but after using the 3cx a bit I'd rather get a pecker for that for the extra power


anyone have experience of adding auxiliary hydraulics?

I've read around online, there's a lot of people mentioning it but they're all sparse on details

some saying put a pin in the extender boom and use the hudraulics from that... but another random mention of adding a solonoid to the hudraulic pump and tee it into the extender boom hydraulics - I think (guess) whay they're really going it just using the hoses for the extender boom

anoter mention says using the stabaliser jack hudraiulics, putting a rope around the leaver and hang it down so it's foot opperated

I think (again guess) there won't be enough flow to a lot of the hydraulics? - factory fit auxiliary hydraulics have a second dedecated pump just for them



I'm a bit lost here... maybe wasting my time... guess it's one of those things if it was easy everyone would do it and there would be a lot of info out there?

 

[8ob]

A pecker needs a fair flow rate/return to work properly, I would divert the front lift arms circuit with a solenoid/switch and leave the rest alone.

Bob

 

[knighty]

It's poring down here so I can't go and look, but I don't know how'd I'd pipe it up not to kink/snap hoses as I used the digger arm

I'd sell my 3cx and get another, but can't see one with aux. hydraulics that isn't a fortune

 

[m_c]

A pecker needs a fair flow rate/return to work properly, I would divert the front lift arms circuit with a solenoid/switch and leave the rest alone.

Bob

I've just had a quick look at a hydraulic diagram for a slightly newer 3CX, and the front lift hydraulics use the same supply as the back arm, via a HPCO from the front spool block.
The auxiliary hydraulics share the power steering pump via a priority valve that is interlinked to the steering valve, so not even just a basic priority valve.

And having just found the optional low flow hammer and extending dipper option, it appears both are controlled in parallel from the HPCO line, in that the boom extends and the hammer are set to be powered in parallel-

 

[jmp49]

Long and complex way, pipe the back acter with rigid lines on the side of the boom/dipper with flexibles spanning the joints that move down to some quick releases, and tee off the feed to the valve block via a control.

Short and really dirty way, do you need the bucket craw? just connect some flexibles to the pecker from them if not and strap up the craw ram and use the craw position on the sticks to activate the pecker. Caps on the craw ram or a small link pipe will stop dirt ingress to that while its connected. I do my bucket mounted wood splitter like this...
The pipe and control on the jacklegs on mine are much smaller diameter than the ones for the digging rams so I didnt consider them a good candidate to divert for decent flow.

Having said that... I don't have a pecking hammer and I've taken a fair bit of concrete out with my 3c3. I get the edge of the bucket teeth under the edge of the slab and use the cam action shape of the bucket to peel it up then just work inwards. If there's no access I smash or use a handheld breaker to make a start hole.
I like a pecker but to drive fence posts in... At the moment I just push them in with the bucket and the weight of the machine, and they either go in or splinter...

 

[Gregb23]

The breaker feed that used to be plumbed into my 3cx black cab was teed off the feed for the boom drop cylinder hose, hardlines with flexible to a quick connect on the dipper. Breaker return was a quick connect fitted to hard lines and flexible as above and then the return was it's own large bore hose plumbed straight into the main return hose going back to the tank. Hammer would operate upon downward pressure on the boom. Removed them all as kingpin was shagged / replaced the carriage and have no need to run any aux at the moment. Other way as stated is extradig feed tee off and then fit the lock pin the extradig, hammer operates from pedal. Mine has the twin pump so one flow for extradig/aux, one for all other functions, with a large return.