Main bearing set 320/09335 JCB Dieselmax standard, genuine

Main bearing set 320/09335, standard is a genuine JCB part for the JCB Dieselmax 444 and 448 engines. The card also lists 320/03243, 320/09473. The photo also shows the crankshaft thrust washers with the set.

Main bearing shells are made of a steel back with an anti-friction lining. When the thin running layer wears through, the layer underneath shows, a sign of excess oil clearance and a reason to replace them. In an engine overhaul the main bearings are always renewed, whatever the state of the crankshaft. The shell size is marked on the back of each shell, showing standard or the undersize value.

Specifications

Compatibility

The part is listed for JCB 3CX and 4CX backhoe loaders. The set is for standard main bearings with side locks; for engines with the lock in the middle of the upper shell choose the main bearing set 320/09202. The catalogue also has the aftermarket version, OEM version and genuine version of this part. Other parts are in JCB Dieselmax engine.

Fitting

Before assembly the main journals are measured with a micrometer and the oil clearance is checked with Plastigage. The shell locks go into their notches, the drilled shells go in the upper housings and the bolts are tightened in the JCB sequence and torque. The shells go in oiled; watch the oil pressure on first start.