Oil leaking from bottom of king post of my 1987 jcb3cx

[Paul w]

Thanks guys after reading what you have written I think I'll repair the bucket ram and try to nurse it through the last few jobs I have for the old girl and then probably sell for spares.there aren't many of these machines in NZ so not sure it is worth much.
Cheers again
Paul w

[Slooby]

Is the leak really that bad?

The complete repair kit, including a new kingpost is around the £1000 mark: https://www.ebay.co.uk/itm/JCB-3CX-KING ... 890.l49292

[MrF]

Wincing at that kit... why would you need a new kingpost carriage automatically?
I think I'd strip the old one first and assess its state and see if just the bush is bad before I got scared by the price of shipping that lot to nz.
Even if the post is bad, can it not be line bored oversize and sleeved back to original size or o/s bushes made up?
If so you can find a engineer locally who could do this in NZ, its just small shop engineering territory. It would have to be pretty badly ovalised to make me want to replace the whole carriage...

The 3c I'm breaking had oil leaking out there badly according to the previous owner, but he did the o rings and seals inside the slew pots and it cured it so it must have been a internal hydraulic leak making its way up the kingpost. Plus 3c != 3cx in that area of course. I was out there yesterday splitting the component parts of it by hand to make it more manageable without a running machine to move it (with a cracked rib after a fall on friday, taking it easy ho hum).

[Slooby]

You can buy it without the Kingpost and Shaft: https://www.ebay.co.uk/itm/JCB-3CX-KING ... Sw1qVeQU0Y

And buy the replacement splined sleeve to allow you to have the old one machine out and then the sleeve welded in: https://www.ebay.co.uk/itm/JCB-PARTS-SP ... Sw1mZdlHTr

Can't seem to find the pin on its own though :/

If you factor in the cost of the machining and welding (assuming you can't do it yourself) then having a new complete carriage probably isn't so out of the way, especially by going to Vicary direct because then it's a fair chunk cheaper!

https://vicaryplant.co.uk/products/copy ... 5a7b&_ss=r

[essexpete]

See post below

[essexpete]

My old 3C leaked for years around the post. It was hydraulic oil getting into that area. Not ideal but better than no oil or water. If it was just the gear oil leaking I might be tempted to try something more viscous in there.

I don't seem to be loosing enough hydraulic fluid for that to be the problem on mine, it tends to be at its worst when the excavator arm is being shaken about because of the free play caused by the wear on the kingpost

I think is was just a bit of a weep on the hydeaulic side.

[Soulman]

I had this issue on my grey cab 3cx (oil leaking from the king post). In my case it was the slew pot seals. I replaced the seals on both slew pots and the issue was resolved completely. its a pretty straight forward repair. before starting make sure the rear of the machine is accessible as u need something to push the slew pots back into place after new seals are fitted. crack open the 4 big bolts a bit but don't remove them fully, then gently pull on the slew lever to slew the back hoe and it will help release the slew pot from the housing for u. Now remove the hydraulic pipes from the slew pot and then proceed to fully remove the 4 bolts and pull off the slew pot cover. then u can replace the seals. when putting the slew pot cover back on, this is where u need some force to push it over the new seals, i used my thwaites dumper to gently apply pressure to the slew pot housing and it pushed it over the seal nicely. (this is why i said make sure the machine is accessible!!)

[gandamaluco]

hello to all jcb fans.
i am one more lucky owner of a jcb 3cx project 8 (phase 2, i think) 1996.
I have a problem identical to this post and I already purchased the seals for slew RAM. it turns out that now that i try to loosen the four large screws (38mm) that hold the covers of the cylinders, it has become an epic job because they seem to be completely glued and I cannot manager to unscrew them. I've already broken a wheel wrench and I don't know what to do. any suggestions or tips for identical experience?
thank you guys ...

[Soulman]

i had to get a 38mm 3/4 inch socket and a strong sturdy driver for it (0.5 meter long). then i additionally needed a 1.5 Meter pipe to slip over the shaft of the driver to get enough torque to open the Nuts. They were tight but it opened them all.

[gandamaluco]

Hello
i managed to open mine too but i broke 2 wrench keys and a pipe wrench in the process... it's hard as i never thouht it could be.
Finally a question... is it normal this deformation on the slew box interior?