Page 293 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

Tappet adjusting in multi-cylinder engine

If tappet adjustment four cylinders’ engine is to be adjusted having firing order 1, 3, 4 and 2, then adjust the tappet
clearance of 1 cylinder, as explain above method, then rotate the crankshaft by half revolution, adjust tapped 3
cylinder again rotate by half revolution and adjust 4th tapped cylinder and finally rotate it by half revolution and
adjust tappet of 2 cylinder. For six cylinders’ engine having firing order 1, 5, 3, 6, 2, 4. Adjust tappet of 1 cylinder
by bringing the pistons on TDC in compression stroke, rotate the crankshaft one third (1/3) revolution every time
and go on adjusting tappet according fining order.
Adjusting tappets Engine
Engine has a camshaft fitted on its head which operates directly rocker arm, the other of rocker operates the
valve through adjusting screw. The system for valves operating mechanism is shown in given figure. In this valve
clearance is adjusted by means of adjusting screw up and down with the help of screw driver and placing the
feeler gauge between valve.

here are some important points While adjusting of valve tappet clearance checking and setting at injection timing
& valve timing
Preparation: Before starting, ensure the engine is cool and in the correct position, usually at top dead center
(TDC) for the cylinder being adjusted.
Locate Specifications: Refer to the manufacturer’s specifications for the correct valve tappet clearance, injection
timing, and valve timing for your engine model.
Access the Valves: Remove any necessary components to access the valves, such as the valve cover.

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CITS : Automotive - Mechanic Diesel - Lesson 85 & 86