DAF CF65, CF75, CF85 Series . Manual — part 459

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Safety instructions

ENGINE BRAKE, PE ENGINE

CF65/75/85 series

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1. SAFETY INSTRUCTIONS

1.1 SAFETY INSTRUCTIONS

Fuel

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Diesel fuel is an extremely

flammable liquid, and must not be

exposed to naked flames or come

into contact with hot surfaces. The

diesel fuel fumes remaining in an

empty fuel tank form an extremely

explosive mixture.

When fuel system components are being

removed, some fuel will escape.

To keep this spillage to a minimum, unscrew the

tank cap to release any overpressure.

Any spilled fuel must be collected, bearing in

mind the risk of fire.

Exhaust gases
Do not run the engine in an enclosed or

unventilated area.

Make sure exhaust fumes are properly extracted.

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Exhaust gases contain carbon

monoxide.

Carbon monoxide is a deadly

colourless and odourless gas,

which, when inhaled, deprives the

body of oxygen, leading to

asphyxiation. Serious carbon

monoxide poisoning may result in

brain damage or death.

Moving parts
Remain at a safe distance from rotating and/or

moving components.

Various fluids
Various oils and lubricants used on the vehicle

may constitute a health hazard.

This also applies to engine coolant, windscreen

washer fluid, refrigerant in air-conditioning

systems, battery acid and clutch fluid.

So avoid inhaling and direct contact.

Electrical short-circuit
Always disconnect the battery's earth connection

during repair or maintenance operations for

which the electric power supply is not required.

ENGINE BRAKE, PE ENGINE

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200324

Safety instructions

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CF65/75/85 series

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General

ENGINE BRAKE, PE ENGINE

CF65/75/85 series

4

7

2. GENERAL

2.1 LOCATION OF EXHAUST BRAKE COMPONENTS

1.

Operating cylinder, exhaust brake

2.

Exhaust brake valve

3.

Supply pressure

4.

Butterfly valve

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ENGINE BRAKE, PE ENGINE

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200324

General

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CF65/75/85 series

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2.2 SYSTEM DESCRIPTION, EXHAUST BRAKE

Switching on the exhaust brake
The exhaust brake consists of an engine brake

operating switch fitted in the cab floor and an

operating cylinder (2) connected to the butterfly

valve in the exhaust pipe.

If the engine brake control switch is operated, a

signal is passed to the engine management

system's electronic unit. The engine

management system's electronic unit interrupts

the fuel supply to the various cylinders. The unit

also energises the exhaust brake valve, causing

compressed air to flow to the operating cylinder

(2). The cylinder closes the butterfly valve in the

butterfly valve housing. The exhaust pipe is then

almost completely closed off.

Controlled discharge of exhaust gases is still

possible through a calibrated hole in the butterfly

valve.

The engine now acts as a compressor, creating a

braking action.

The higher the engine speed, the greater the

braking action of the exhaust brake.

Switching off the exhaust brake
If the engine brake control switch is released, the

fuel supply to the various cylinders will be

re-instated and the butterfly valve will be

re-opened.

I400533

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1.

Butterfly valve operating cylinder

2.

Exhaust brake valve

3.

Supply pressure

4.

Butterfly valve