JCB 3c problems

[browuk]

Hi all, with the weather turning, I have got the old girl out to do some work but would really like to get its issues resolved to make using it a bit more easier.

I will start with My main problem, the gearbox / clutch, it doesn't slip, it actually has so much torque but the issue is that when I depress the clutch pedal, it doesn't completely disengage, makes loading really hard as when you push into a mound to load the front bucket, 90% of the time, the only thing I can do is stall it to get it out of gear. when going into all gears, it crunches like crazy, it seems like it needs a small mount of adjustmant as when driving it, if I depress the pedal and rev, it barely moves, I can then let go of the pedal and with enough revs, it could wheelie.
I have adjusted the rod underneath from the pedal to max.

any help of this please?

[agrimax]

Should have inch and a half free play on the clutch pedal.Don't know if you have a Fordson or Nuffield unit,but if it is the BMC engine,you need to remove the plate on the side of the top housing and see if the release bearing is as close as possible to the toggle levers on the pressure plate without touching,when the pedal is released.Might be worn or out of position toggles,worn release bearing or shot spigot bearing too.
The fact that it's not slipping makes me think that proper adjustment is the problem due to wear in linkage pins etc, and you are not getting enough push inwards on the release bearing.

[Johnno]

Hi all. I have just aquired a late 3c3, (twin air filter element). It's down on power, misfiring, stalling when under load etc. I'm going to change all the filters, top up the hydraulic oil etc. Hydraulics, movements etc all ok. Any tips or typical problems with these (98 NT Engine)?

Maybe fuel tank disturbed, rubbish in tank, during transport? Runs OK at first start, starts well too, but dies away and loses power. Fuel problem maybe first port of call?

Any tips chaps?

[TullyveeryClassicJCB]

Johnno it sounds almost certain to me that you have dirt clogging up the filter inside your injector pump. This is a very common problem. Theres a range of other things it could be but it all comes down to a feed of dirt from your tank. I remember one digger and all its problem was that someone had forgot to put the small internal O ring onto the centre of the fuel filter.

[Johnno]

Thanks William, I am in the process of printing the manuals from the site (a real Godsend, thanks uploader!!), and will give the fuel system a bit of attention. Is the filter inside the injector pump accessible by an amateur like me, or is it a specialist thing?

[Julian]

Thanks William, I am in the process of printing the manuals from the site (a real Godsend, thanks uploader!!), and will give the fuel system a bit of attention. Is the filter inside the injector pump accessible by an amateur like me, or is it a specialist thing?

I've little knowledge of JCB specifics, but assuming it's a Lucas DPA pump (AKA Rotodiesel/Stanadyne) then the filter in the pump is a simple ''last chance'' plastic gauze that is behind the fuel pipe inlet union. Remove the pipe and then undo the union and you'll see it there - easy peasy! I think there may also be a spring and steel ball check valve there too - watch you don't lose it!

Julian

[TullyveeryClassicJCB]

Its not a specialist thing but be very clean and careful. Theres a springand a top hat shaped piece of metal. When you get all that out of the way stick your wee finger in and it might come out easy and it might not. Its a robust plastic filter and is worth about 50p so dont worry about it breaking.

[browuk]

thanks agrimax.

its the nuffield bmc 4/65 i think, there is a plate on the side with 4 bolts in corners and 1 in the middle sticking out, is this the one you mean.

I too think the clutch disc itself is ok becauese there is still so much torque there whichever gear im in, I had sort of come to the the conclusion it was the bearing or pressure plate at fault , it just isn't clearing enough to spin freely when pedal depressed.

so if I remove this plate on the side, I should be able to see something yea?

thanks

[Julian]

thanks agrimax.

its the nuffield bmc 4/65 i think, there is a plate on the side with 4 bolts in corners and 1 in the middle sticking out, is this the one you mean.

I too think the clutch disc itself is ok becauese there is still so much torque there whichever gear im in, I had sort of come to the the conclusion it was the bearing or pressure plate at fault , it just isn't clearing enough to spin freely when pedal depressed.

so if I remove this plate on the side, I should be able to see something yea?

thanks

Remember, assuming that you've adjusted the clutch pedal properly to allow just a little clearance, that the clutch drag you are experiencing is normally caused by a warped pressure plate or disc, oil contamination or maybe a lose friction segment.

Don't allow it to ''crunch like crazy'' as you say, or you'll be knocking the corners off the dogs in the gearbox and having the thing start jumping out of gear necessitating a visitation to Mr gearbox internals

Julian.

[agrimax]

thanks agrimax.

its the nuffield bmc 4/65 i think, there is a plate on the side with 4 bolts in corners and 1 in the middle sticking out, is this the one you mean.

I too think the clutch disc itself is ok becauese there is still so much torque there whichever gear im in, I had sort of come to the the conclusion it was the bearing or pressure plate at fault , it just isn't clearing enough to spin freely when pedal depressed.

so if I remove this plate on the side, I should be able to see something yea?

thanks

Yip.That's the plate.With the engine running and the clutch up,the bearing should not be turning.Chances are it will be,if you have all the adjustment wound up.As Julian has said,the clutch plate could be warped.