I have an old JCB 3C MII with one of a million problems........The most
important one right now drawback in digging power. I suspect this may
be a lack of hydraulic oil as there is a whiney noise when I used the
hydraulics, however I was wondering if maybe the hydraulic filter also
needs replacing?

Does anyone have any experience

Thanks

I have an old JCB 3C MII with one of a million problems........The most
important one right now drawback in digging power
I suspect this may
be a lack of hydraulic oil as there is a whiney noise when I used the
hydraulics, however I was wondering if maybe the hydraulic filter also
needs replacing?

If the tank has a sight glass and you cant see the oil in it then top it up.
Also the suction strainer in the hydraulic tank may be blocked,I am not
referring to the main hydraulic filter,look under the tank and you will find
a plate,drain the oil and remove the plate,inside you will find the suction
strainer,remove and clean it,see how you go from there
Change the main filter avery 500 hrs if you are a regular user.
Change the oil completely every 2000 hrs.
Clean the air filter WEEKLY by blowing out from inside with an airline.
Change 500hrs.


If no improvment after topping up with oil then look and listen for leak
past in the rams. If you can hear oil transfer when operating the "crowd in"
lever when the bucket is at full travel then may be worth new seals.
Sometimes the pressure releif valve sticks in the ports by the valve block.
Careful examination will help to see if any of the spools are leaking or
allowing early pressure let off.

HTH

many thanks, will check these out.

Cheers

PL

YTC449 wrote:
If no improvment after topping up with oil then look and listen for
leak past in the rams. If you can hear oil transfer when operating
the "crowd in" lever when the bucket is at full travel then may be
worth new seals.

One other unlikely possibility, but I'll tell you about it cos it's just
happened to us on a borrowed JCB 3CX (our Case digger is out of action
due to a fracture/leak in the chassis which doubles as the hydraulic oil
tank. A real bugger to get to and weld up, it's now done and we are
ready to re-assemble the dozens of bits that had to come off!) The JCB
seems to have been poorly maintained and was losing power in general
when the engine was under pressure. A good cleaning out of fuel line and
filters sorted this out, so might be worth checking on yours too. Then
it still wasn't digging well but we only had a day or twos urgent work
so my husband carried on, but at the end of the first day it got worse
and then the dipper arm stopped working altogether. We thought there was
something seriously wrong with the ram (panic! expensive job on a digger
you have only borrowed for a couple of days!) but a phone call to our
friendly expert in Ireland immediately identified the problem. Inside
the ram there is a big nut/seal arrangement and it seems it's not
uncommon for these to gradually work loose, leak and then come off
altogether, which is what had happened in our case. We dismantled the
ram, got the nut out, (my husband had to file down the threads a bit
where they were damaged) but managed to put the whole lot back together
again and the JCB is digging fine again now - although still nowhere
near as well as the Case apparently. I have no idea whether all JCB rams
work in this way but thought it worth mentioning just in case.....

HTH .
--
Holly, in France
Holiday Home in Dordogne (now with DIYed swimming pool!)
http://la-plaine.chez.tiscali.fr/