Hi,
I have recently bought a 1990 JCB 3CX without Gearbox and restored it with the gearbox and all other necessary parts, The engine works fine and hydraulic system is also working good.

But when I try to move the machine forward/backward it revs up but it doesn't move. But at the same time when I lift the machine with the hydraulic legs and then move the tires they work fine. Please help fellas

Vaishakh Menon, January 2016

The solenoid contacts could be loose. The vibration will make it hit and miss. I mean the actual plug socket itself. The steel contact can back up into the plug and you think its connected. But loosens with movement. Take the contacts out and test with naked cable to ensure a good connection. Worked for me.

Desperate, February 2023

I would suggest you look at the relay behind the instrument panel. There not expensive around £10. I had a very similar problem with my jcb3cx, it suddenly stopped moving and I could hear the relay click. Its only when I used a tester on each terminal it started working again.

Kash, January 2016

There is no clutch in these machines.

Vaishakh Menon, January 2016

Have you considered that there might be an issue with the clutch - these things do have a clutch I suppose?

Good Luck..., January 2016