Dipper cylinder barrel 561/70177 JCB 3CX/4CX, aftermarket

Dipper cylinder barrel 561/70177 is an aftermarket part for the JCB 3CX and 4CX backhoe loaders.

In a cylinder repair the barrel is one of the most expensive and most stressed parts: its bore works constantly under pressure against the piston seal, while the outside is exposed to stones and knocks. Dirty oil leaves lengthwise score marks in the bore, which make the cylinder leak past at one position and the load slowly sink. In a dented or bent barrel the piston jams and the seals tear. With a new barrel, a seal kit and, if needed, a new piston and gland, the cylinder is brought back close to factory condition. After the repair, run the cylinder through its full stroke and check it for external and internal leaks. Score marks in the bore often start with a worn wiper seal in the gland: dust and sand that get inside scratch the barrel along with the piston seal. That is why the wiper is always renewed during the repair. Choose the barrel by part number and compare it with the old one.

Specifications

Compatibility

The barrel belongs to the dipper cylinder. Other parts are in JCB hydraulic cylinders.

Fitting

Do not use sharp tools when fitting the seals; fitting cones and clean oil help the seals go in without damage. Check the lip direction of the new seals against the old ones, since a seal fitted the wrong way round leaks at the first pressure.