Land Rover Diesel Distributor Pumps Bosch Bosch Manual

Load-dependent
compensation
Depending upon the diesel engine’s load,
the injection timing (start of delivery)
must be adjusted either in the “advance”
or “retard” direction.
Load-dependent start of delivery
(LFB)
Assignment
Load-dependent start of delivery is de-
signed so that with decreasing load 
(e.g., change from full-load to part-
load), with the control-lever position un-
changed, the start of delivery is shifted 
in the “retard” direction. And when en-
gine load increases, the start of delivery...

lever is used to input a given full-load
speed. If this speed is reached and the
load is less than full load, the speed 
increases even further, because with a
rise in speed the flyweights swivel
outwards and shift the sliding sleeve. On
the one hand, this reduces the delivery
quantity in line with the conventional 
governing process. On the other, the 
sliding sleeve’s control port is opened by
the control edge of the governor-shaft
groove. The result is that a portion of the
fuel now flows to the...

Cold-start compensation
The diesel engine’s cold-start charac-
teristics are improved by fitting a cold-
start compensation module which shifts
the start of injection in the “advance”
direction. Operation is triggered either 
by the driver using a bowden cable in 
the cab, or automatically by means of 
a temperature-sensitive advance mech-
anism (Fig. 11).
Mechanical cold-start accelerator
(KSB) on the roller ring
Design and construction
The KSB is attached to the pump 
housing, the stop lever being...

causes the stop lever, the shaft, the inner
lever and the ball pin, to swivel and
change the roller ring’s setting so that the
start of delivery is advanced. The ball pin
engages in a slot in the roller ring, which
means that the timing-device piston
cannot rotate the roller ring any further in
the “advance” direction until a given
engine speed has been exceeded.
In those cases in which the KSB is 
triggered by the driver from the cab 
(timing-device KSB), independent of the
advance defined by the timing...

Design and construction
The hydraulic cold-start accelerator
comprises a modified pressure-control
valve, a KSB ball valve, a KSB control
valve, and an electrically heated ex-
pansion element.
Method of operation
The fuel delivered by the fuel-supply
pump is applied to one of the timing 
device piston’s end faces via the injection
pump’s interior. In accordance with the
injection pump’s interior pressure, the
piston is shifted against the force 
of its spring and changes the start-
of-injection timing....

Engine shutoff
Assignment
The principle of auto-ignition as applied
to the diesel engine means that the 
engine can only be switched off by
interrupting its supply of fuel.
Normally, the mechanically governed
distributor pump is switched off by a 
solenoid-operated shutoff (ELAB). Only
in special cases is it equipped with a 
mechanical shutoff device.
Electrical shutoff device 
(ELAB)
The electrical shutoff (Fig. 17) using the
vehicle’s key-operated starting switch is
coming more and more to the...

Testing and calibration
Injection-pump test 
benches
Precisely tested and calibrated injection
pumps and governors are the prerequisite
for achieving the optimum fuel-con-
sumption/performance ratio and compli-
ance with the increasingly stringent
exhaust-gas legislation. And it is at this
point that the injection-pump test bench
becomes imperative. The most important
framework conditions for the test bench
and for the testing itself are defined in 
ISO-Standards which, in particular, place
very high...

Nozzles and 
nozzle holders
The injection nozzles and their respec-
tive nozzle holders are vitally important
components situated between the in-line
injection pump and the diesel engine. 
Their assignments are as follows:
– Metering the injection of fuel,
– Management of the fuel,
– Defining the rate-of-discharge curve,
– Sealing-off against the combustion
chamber.
Considering the wide variety of com-
bustion processes and the different forms
of combustion chamber, it is necessary
that the shape,...

Throttling pintle nozzle
The throttling pintle nozzle is a pintle
nozzle with special pintle dimensions.
The special pintle design serves to define
the shape of the rate-of-discharge curve.
When the nozzle needle lifts it first of all
opens a small annular gap so that only a
small amount of fuel is injected (throttling
effect). 
As needle lift increases (due to pressure
rise), the spray orifice is opened increas-
ingly until the major portion of the injec-
tion (main injection) takes place towards
the...

Hole-type nozzles
Application
Hole-type nozzles are used with in-line
injection pumps on direct-injection en-
gines. 
One differentiates between:
– Sac-hole, and 
– Seat-hole nozzles.
The hole-type nozzles also vary accord-
ing to their size:
–T
ype Pwith 4 mm needle diameter,
and
–T
ype Swith 5 and 6 mm needle dia-
meters.
Design and construction
The spray holes are located on the en-
velope of a spray cone (Fig. 4). The num-
ber of spray holes and their diameter de-
pend upon:
– The injected fuel...