Camshaft, Lifters and Push Rods: Description and Operation

VALVE TRAIN
DESCRIPTION
Hydraulic roller valve tappets, providing automatic lash adjustment, ride on camshaft lobes and transfer up and down motion to the rocker arms through push rods. The rocker arms press down on and open the valves.

CAMSHAFT
- The camshaft is installed in the cylinder block and is supported on four camshaft bearings.
- Thrust loads and end play are limited by a camshaft thrust plate installed on the front of the camshaft.
- The camshaft position sensor (CMP sensor) drive gear is located at the rear of the camshaft.
- The CMP sensor drive gear is part of the camshaft casting.

ROCKER ARMS
The rocker arms are pedestal-mounted and pivot on rocker arm seats bolted to the cylinder heads.

VALVES
The valves are arranged alternately: intake valve/exhaust valve. Flexible fuel vehicles are equipped with unique exhaust seat inserts.