PLATE-MOUNTING 3690499 - Caterpillar

Illustration 1 g00807910
Connections for a two-piece camshaft
(1) Dowel
(2) Spacer
(3) Bolt The 3512 and 3516 Engines have two-piece camshafts. Dowel (1) in one section of the camshaft goes through spacer (2) into the other section of the camshaft. The sections are joined by bolts (3). Each 3516 camshaft is supported by nine bearings. Each 3512 camshaft is supported by seven bearings.The 3508 has one-piece camshafts. Each 3508 camshaft is supported by five bearings.As the camshaft turns, each lobe moves a lifter assembly. Each cylinder has two lifter assemblies. Each lifter assembly moves a pushrod and two inlet valves or two exhaust valves. The camshafts must be timed with the crankshaft. The relation of the camshaft lobes to the crankshaft position cause the valves in each cylinder to operate at the correct time.