Page 1 of 1

JCB 3CX 1982: changing water pump and fan belt

Posted: Tue Jul 12, 2011 1:13 pm
by ErwinPWP
Hi guys,

I’ve a 3CX 2WD White Cab from 1982 (Perkins non-turbo engine) with a much worn water pump. The drive shaft of the pump has a lot of radial play. To avoid that one time the shaft will break and the fan will hit the radiator I’ll have to exchange this pump.

Does anyone know if you can replace the pump while the radiator is still in place?

Another question I have is about changing the fan belt. What is the easiest way to fix this job? The problem is that the drive shaft of the main hydraulic pump goes ‘thru’ the fan belt.

I was thinking to separate the pump drive shaft flange from the crankshaft pulley in order to create a small space to be able to slide the fan belt thru.
But I’ve no idea if this is possible (it will depend on how far you can slide the pump drive shaft towards the pump).
Hmmm I was just thinking that you don't have to slide the shaft towards the hydraulic pump because you can easily ‘bent’ the shaft because it has 2 universal joints (cross axle)! :think:

I’ve no service manual available so I’ve no idea about the way of working to fix those jobs.

Anybody some experience/suggestions?


Cheers,

Erwin from Belgium

Re: JCB 3CX 1982: changing water pump and fan belt

Posted: Tue Jul 12, 2011 2:19 pm
by martyn williams
The gang on here will be able to help I am sure. I used to fit two belts to the machines I worked on. The "spare " was cable tied clear of all rotating parts.So if one belt needed changing you just cut the ties on the spare,slackened the adjuster,refit the new belt and adjust and away you go. Saved messing around with pump couplings.And also got the machine back in service much quicker. :thumbup:
Martyn

Re: JCB 3CX 1982: changing water pump and fan belt

Posted: Tue Jul 12, 2011 10:22 pm
by Mark.Rive
Hi Erwin, to replace the fan belt you need to remove the 4 bolts holding the pump drive shaft flange from the front pulley of the engine. The shaft is on a sliding spline and will retract enough for you to replace the belt. I agree with Martyn that a spare belt should be installed and cable tied out of harms way til needed.

While the belt is off, remove the fan blades and drive pulley from the water pump shaft/flange. You will have enough access to unbolt and remove the worn water pump without removing the rad. Dont forget to drain the cooling system, but its a good idea to drain after you've done the work underneath :thumbup: Mark