INTRODUCTION - ENGINE CRANKCASE

3.2 JTS

Technical specifications

It is made entirely from aluminium alloy and is the main structural part of the engine. Its purpose is to contain and support all the crankshaft components.

In addition to housing the cylinder liners/bores, the engine crankcase supports the moving assemblies in the engine (pistons, connecting rods, crankshaft, camshaft, etc.), the fixed elements (cylinder head, oil sump, timing cover) and the auxiliary components (alternator, starter motor, climate control compressor, etc.).

The dry type cylinder liners/bores are incorporated in the cylinder block/crankcase.

Special ducts, in the crankcase walls, allow the flow of coolant and lubricant oil.

The crankshaft is supported by four bearing supports.

The crankshaft is fastened to the crankcase by means of four main bearing caps each of which has six fastenings, four vertical and two lateral; the diagrams below show the six fastenings for each bearing cap.

There are three twin nozzle oil jets in the lower part of the crankcase, one for a right bank cylinder and one for a left bank cylinder, for cooling/lubricating the pistons.

2.2 JTS

SPECIFICATIONS

It is made entirely from aluminium alloy, comprising two sections, the actual cylinder block/crankcase and the base plate.

The crankshaft is supported by five main bearings.

The crankcase also houses two counter-rotating shafts that are mounted on a central bush and a ball bearing at the front and the rear.

Special channels in the crankcase walls carry coolant and lubrication fluid.

The lower part of each cylinder contains an oil jet that sprays oil on the piston crown.

1. Base plate

2. Cylinder block/crankcase

3. Engine oil filter cartridge and water-oil heat exchanger support