Jcb 3c ii ram problem

[browuk]

Hi all, first post here, been lurking but not had to post until now.

My question, the top ram on my jcb backhoe will come in (push arm out) but only with relatively high revs then as soon as you let off the lever, it drops straight back, also, there is no power in it when digging it just wont pull the bucket through the dirt, all other movements work fine, its just this one,a hose burst on it a while ago and it sat doing nothing, have replaced hose now, Have topped up fluid but no go.

any ideas.

thanks

[bsbplant]

Ram seal gone inside the ram ??

[browuk]

Ram seal gone inside the ram ??

Can anyone else confirm this is likely the problem and if so, how do I change it?

thanks again

[essexpete]

I suppose ther could be a spool leak but pistons seals most likely. Trapped air could be a problem. If you back a union and power it gently you could eliminate that. Usually cycling the ram will get rid of air. Don't get close to hydraulic oil squirting under pressure.
To change the piston seal will rquire the removal of the end cap which screws on. You will then have to pull out the rod with the gland and piston. You might find a seal kit with a JCB agent or independant specialist like Vicary plant. You might have a job undoing the end cap without the correct C spanner. I made something using an old heavy G clamp.

[browuk]

Hi thanks, been out at it today to take a look and the previous owner has welded the cap on the end so I aint gonna be getting to the seals, if it is the seals at fault, looks like I will have to replace the ram. on that note, before I take it off, does anyone know what this ram is called (boom possibly) and what is the approx weight?

[steve ball]

The top ram's normally referred to as the dipper ram. I had to change mine recently and went for a reconditioned one.

The end cap on mine was also welded on (all the way around the circumference plus 2 x 1" wide straps welded from the end cap across the joint and onto the cylinder body!).

I would guess that it weighs in the order of 40 - 50 kg. It was fairly easy to change using a car engine hoist to take the weight whilst trying to drift the pins in. Take the opportunity to change the spring steel bushes at the same time.

[browuk]

The top ram's normally referred to as the dipper ram. I had to change mine recently and went for a reconditioned one.

The end cap on mine was also welded on (all the way around the circumference plus 2 x 1" wide straps welded from the end cap across the joint and onto the cylinder body!).

I would guess that it weighs in the order of 40 - 50 kg. It was fairly easy to change using a car engine hoist to take the weight whilst trying to drift the pins in. Take the opportunity to change the spring steel bushes at the same time.

Hi Steve, thanks for that, sounds like mine, its the same on the bucket ram too but thankfully that function well.
Do you mind me asking how much you paid for a recon one?

[steve ball]

The reconditioned ram cost me about £200.

Some places offer them on a service exchange basis but given the "bodge" that was performed on mine at some stage, this wasn't really an option.

[browuk]

£200 seems good but actually got myself a used one from breakers apparantly no problems with it and end cap untouched, paid £100 and sorted deliery to france for £38+vat so not bad if it fixes my problem.

[TullyveeryClassicJCB]

The Loader on my 3c3 is very weak and slow when raised and drops down slightly after raising. There is also a slight sound like a ping or crack when rising. How can I be sure the problem is with a ram and not with the valve block?