Who knows JCB?

[Jock The Rock]

Gday

Just wondering if there are any other JCB mechanics on here?

[p38arover]

JCB the brand or the Pommie generic (but not Aussie) term for a back hoe?

[oldyella 76]

Got a JCB backhoe and telehandler, not a mechanic but what's wrong????

[Blknight.aus]

I've worked on the john deere stuff and a couple of others. its all the same principles if its hydraulic and not electrics, whats up?

[JGARDE]

I worked for jcb in Ireland for 7 years good machine

[Jock The Rock]

Sorry I sort of dropped off the radar for a bit there

Nothing to major

I'm plumbing a tilt/quick hitch onto a top spec machine. (Piston pumps closed centre MCV)

The operator wanted tilt and e-dig simultaneously

I was just interested to see if anyone else had much experience with that sort of thing

I have a plan, just plumbing it up at the moment to see if it will work

[Blknight.aus]

Sorry I sort of dropped off the radar for a bit there

Nothing to major

I'm plumbing a tilt/quick hitch onto a top spec machine. (Piston pumps closed centre MCV)

The operator wanted tilt and e-dig simultaneously

I was just interested to see if anyone else had much experience with that sort of thing

I have a plan, just plumbing it up at the moment to see if it will work


how goods the operator? If you dont put flow compensation in if he operates both at the same time one will sit waiting for the other to load up before moving. If hes a good operator the cheap and simple solution is a pair of t pieces into a pair of DCV's one for each function which I'm guessing is about the way you're headed?

[Jock The Rock]

how goods the operator? If you dont put flow compensation in if he operates both at the same time one will sit waiting for the other to load up before moving. If hes a good operator the cheap and simple solution is a pair of t pieces into a pair of DCV's one for each function which I'm guessing is about the way you're headed?

Not really that easy, the other backhoes I've done recently were similar to that. Priority flow control valve into a double acting Ctype3 with cross port reliefs switched by a rocker switch mounted in the joysticks. Thats because they had gear pumps and an open centre MCV

This machine has a variable displacement piston pump with a closed centre MCV, so it requires load sense from the service to stroke up the pump and give you flow to operate the tilt at normal speed.

Normally this requires a particular valve which is worth around 3 grand, but I've come up with this other idea which hopefully will work tomorrow

[Blknight.aus]

be interested in what your solution will be....

[JGARDE]

How old is the machine what you trying to do make it work faster??

[MarknDeb]

Gday i have only operated the 3cx so unless thats the machine you are asking about



OK i read on, iam an operator not a mechanic so of no real help

[Jock The Rock]

be interested in what your solution will be....

Got it to work in the end

Normally we divert oil from e-dig to tilt and then use the controls in the machine to operate tilt while holding in a momentary switch. So either you have e-dig or tilt

Instead I robbed oil from the front loader valve 4-1 bucket circuit (oil flows from the pump to both the loader valve and backhoe control valves) in to a 6 port diverter. Because this is a servo control machine it was possible to use the existing electronics to only switch the divertor when the backhoe hydraulics are activated. I then used a double acting ctop3 with shuttle valves to control the pilot pressure to the loader 4-1 circuit. This is switched by a rocker switch on the joystick, also only powered when the backhoe electrics are activated. The 4-1 MCV slice already has all the provisions for load sense hence it will stroke up the pump allowing operation of the tilt individually

[Blknight.aus]

impressive, I hadnt thought of robbing the hyds from the front end, I was running the assumption that it all had to come from the hoe end hydraulics.