MANIFOLD-EXHAUST 8N9236 - Caterpillar

Do not operate or work on this product unless you have read and understood the instruction and warnings in the relevant Operation and Maintenance Manuals and relevant service literature. Failure to follow the instructions or heed the warnings could result in injury or death. Proper care is your responsibility.
The function of the Intake Valve Actuation (IVA) piston is extremely sensitive to the torque applied to the jam nut. When the torque applied to the jam nut is higher than what is recommended in the service documentation, the piston may become sticky or seize causing erratic operation. Symptoms of a sticky or seized IVA piston could be misfire, white smoke, or -7 diagnostic codes. The piston will also be sticky or seized, but will move freely when the correct torque is applied.
Illustration 1 g06285896Torque jam nut of the IVA ... 50 5 N m (37 4 lb ft)