SAFARI

4 DLT ENGINE

diaphragms within the boost controller. The boost

pressure is piped and connected to the chamber

formed between the two diaphragms. The diaphragms

sense the variation in the boost pressure and maintain

the balance between the fuel delivery and the boost

pressure, by continuously varying the pressure behind

the actuating pistons.

Operation :

At cranking speeds, the assembly is held in Excess

Fuel position (Full Boost) by a spring. As the engine

picks up, the transfer pressure builds up behind the

actuating pistons and moves the assembly to

minimum fuel position.

As the boost pressure increases with the rise in engine

speeds, the diaphragm responds and allows the

pressure to leak acting behind the actuating pistons.

This allows the return spring to move the assembly

axially towards increased fuel delivery position.

6. EGR THROTTLE SWITCH

The EGRThrottle Switch fitted on to the throttle lever

is used to sense the position of the throttle lever. The

output is given EGR controller.

7. COLD IDLE ADVANCE

The Solenoid operated Cold Idle advance is driven by

the glow plug timer (GPT) and overrides the normal

advance control mechanism when the engine is cold.

This normally functions in conjunction with the engine

Pre / Post heat system and operates only when the

electrical input is supplied to it by the GPT.

AIRVENTING

The DPC pumps are self venting pumps and therefore

allows the air entering into it, to go out through the

return line. However, it is recommended that whenever

the fuel lines are disconnected, the system is to be

primed in order to fill the system with fuel and remove

the air present in the system completely.

Procedure

Energise the Fuel Shut-Off Solenoid (Switch 'ON'

the ignition switch).

Loosen the following vent screws

On the banjo bolt at the filter outlet

On the FIP timing chimney plug

(See fig. 166)

Loosen the priming pump plunger

and actuate

the pump until clear fuel comes out of the vent

screw

Tighten the vent screw

Continue actuating the priming pump plunger until

clear fuel is seen coming out from the vent

screw

Tighten the vent screw

and then the priming

pump plunger

Loosen one of the HP connections at the injector

end. Crank the engine for few seconds; and see

that the fuel flows out of the injector line.Tighten

the HP connection.

Start the engine and see that there is no fuel

leak from any of the points/connections.

Fig. 166