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What happens if valve clearance is too low?

What happens if valve clearance is too low?

Too much or too little valve clearance can result in poor performance or a rough idle because the engine can’t “breathe” normally and operate at peak efficiency. If there’s too little valve clearance, the valves won’t fully close, causing excessive heat, and the engine will lose power.

What is engine valve clearance?

Valve clearances are the small gaps between the tops of the valve stems and the part of the mechanism which presses on them to open the valves . Check the clearances at regular intervals as specified in the car service schedule, and adjust if necessary. Reset the clearances whenever the cylinder head has been removed.

What kind of engine does a Caterpillar C18 have?

The Cat ® C18 Industrial Diesel Engine is offered in ratings ranging from 429-522 bkW (575-700 bhp)@ 1800-1900 rpm.

How to adjust the clearance on a variable valve actuator?

Slide the feeler gauge between the actuator rod and the intake rocker arm. Continue turning the adjustment screw until a slight drag is felt on the feeler gauge. Remove the feeler gauge. Set the clearance to 0.50 ± 0.08 mm (0.020 ± 0.003 inch).

What does the control valve do on a cat engine?

The control valve contains a coil and a cartridge assembly. The cartridge assembly contains a spool. The spool is normally closed. When the spool is closed, the oil is contained in the rail. The ECM sends a signal to the coil in order to fully open the spool.

When does the ECM command the control valve to close?

The ECM checks the temperature of the coolant. The ECM commands the control valve to close when the coolant temperature exceeds 20 °C (68 °F). This allows the temperature of the oil in the rail to warm up. The ECM commands the control valve to open. The ECM samples the rail pressure. The ECM commands the control valve to close.