DAF CF65, CF75, CF85 Series . Manual - part 466

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Inspection and adjustment

XE ENGINE FUEL SYSTEM

CF65/75/85 series

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3.2 INSPECTING INJECTOR OPENING PRESSURE

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Fuel or test fluid discharged by an 

injector may penetrate the skin, 

seriously harming your health. Make 

sure the fuel jet is discharged into a 

suitable container.

1.

Disconnect the earth lead from the battery 

terminal.

2.

Remove the fuel injector pipes as a set and 

close the connections on the pump units 

immediately.

Note:

The opening pressure of the injectors can be 

tested using an injector test pump 

(DAF no. 0694966). The advantage of this 

method is that the injectors need not be 

removed from the engine.

3.

Check the opening pressure of the injectors.

Instructions for the use of the injector test 
pump
1.

Before the injector test pump is used, it must 

first be bled.

Remove the pump reservoir filler plug and fill 

the reservoir with test fluid. The fluid level 

must be approximately 1 cm below the top 

rim.

2.

Tilt the pump until the line with the word 

"BLEED" is horizontal.

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Inspection and adjustment

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CF65/75/85 series

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3.

Press the bleed pin (1) and simultaneously 

turn the crank (2) clockwise to the stop.

During this procedure, air bubbles will come 

to the surface in the reservoir. Now turn back 

the crank, fill the reservoir again and repeat 

the process until no more air bubbles come 

to the surface.

Now release the bleed pin. Continue turning 

the crank until fuel escapes on the delivery 

side.

4.

If necessary, fill the fuel reservoir and screw 

back the cap.

5.

The pump is now ready for use.

Inspecting opening pressure with an injector 
test pump
1.

Keep the test pump more or less horizontal.

2.

Loosen the test pump filler cap by half a turn 

so that air can enter the reservoir.

3.

Turn the test pump crank clockwise. The 

compression will now start. Watch the fluid 

level in the test pump.

4.

Carefully determine the opening pressure of 

the injector. There is no harm in repeating 

the test two or three times.

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If the test is repeated too often, 

however, the test fluid deposited on 

the piston may cause damage to the 

engine when it is started.

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Inspection and adjustment

XE ENGINE FUEL SYSTEM

CF65/75/85 series

4

8

3.3 INSPECTING INJECTOR OPERATION

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Fuel or test fluid discharged by an 

injector may penetrate the skin, 

seriously harming your health. Make 

sure the fuel jet is discharged into a 

suitable container.

Evaluating the injector's spray pattern, spray 

angle, and sound is practically impossible. New 

injectors or injectors that have been in use for 

some time cannot be tested in this way.

1.

Place the injector on an injector tester.

2.

First allow the injector to inject a number of 

times.

3.

Inspect the injector for:

-

opening pressure

-

leakage

-

injector nozzles.

Opening pressure
1.

Inspect the discharge pressure by slowly 

building up the pressure inside the injector.

Leakage
1.

Dry the nozzle immediately after the final 

injection.

2.

Increase the pressure to the opening 

pressure minus 20 bar. Within approx. 10 

seconds, fuel must have ceased to leak from 

the nozzle. A moist nozzle is permitted. If the 

injector does not pass the oil leakage test, it 

must be replaced.

Injector nozzles
1.

Quickly build up pressure in the injector and 

check whether all the nozzles are fully open.

2.

Clean the injector if possible. See 

"Cleaning".

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Inspection and adjustment

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CF65/75/85 series

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3.4 INSPECTING FUEL SYSTEM FOR LEAKAGE

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To prevent deformation of the fuel 

tank, the delivery pressure in the fuel 

tank must not exceed 0.4 bar.

1.

Fit a pressure reducer valve connection on a 

tank cap (without bleeder) and connect the 

tank cap to the fuel tank.

2.

Dry the inspection points.

3.

Pressurise the fuel tank (maximum 0.2 bar).

4.

Unscrew the union nut (A) a few turns to 

check whether there is leakage in the non-

return valve. If there is leakage, the banjo 

bolt should be replaced.

5.

Check the whole fuel system (low-pressure 

section) for leaks.

6.

De-pressurise the system and replace the 

banjo bolt with integrated non-return valve 

on the rear of the filter housing with a normal 

banjo bolt.

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