JCB 3c problems

[Johnno]

'afternoon Gents,

Well, the old beast is running well now that it's getting a proper fuel flow, thanks for the tips. No excessive smoke, proper power, starts on first or second compression, even if expectedly a little worn.

When I got it, the bloke said the clam on the 4in1 won't work and had been welded up for years, well not being one to believe that something won't go until I've tried it myself, I cut the welds and got it opening and closing.

However, it works for a while then just goes totally limp, the clam that is, then after I've forced it open with the tip/crowd action, it'll work for a while, then fail again.

I think it's something to do with the spool control valve, a secondary relief valve or wear or something.

Any tips or common problems? The confusing thing is, that one moment it will work seemingly fine, if a little under powered, the next, it's as if there's a total loss of hydraulic pressure. Seems like some sort of control problem, maybe a dodgy relief, as I say.

I think the clam has had some stick, as the lower jaw is a little warped.

Thanks in advance for any guidance lads.

[Johnno]

Hi All,

One of the hose unions on the steering ram came loose on my machine, at first I thought it was a pipe gone, so I nursed it back to the shed (leaving a reasonable trail of oil where i had to make tightish turns) and looked at the pipe. I realised that the union was loose rather than the pipe split and tightened it. The steering lock movement to offside is fine, but the lock to nearside has lost some if it's range and has gone stiff (this is the side that the union feed came loose on). Maybe just loss of hydralic oil? I changed the main hydraulic filter and about 1/3 - 1/2 the hydraulic oil at the same time when I bought the macine about a year ago, so the main filter shouldn't have failed, and all the other hydraulics seem to be ok....

Any help or suggestions greatly appreciated chaps, thanks in advance.....