Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual — part 586

FUEL SYSTEM 6C – 3

Item

4JA1TC 4JH1TC

Injection pump type

BOSCH VP44

(electronic controlled fuel injection pump)

Injection nozzle type

Hole type (Double spring type)

Number of injection nozzle orifices

5

Injection nozzle orifices

mm (in)

Inside diameter

0.17 (0.0067)

0.21 (0.0083)

Injection

nozzle

opening

kg/cm

2

(psi/MPa)

1st: 199 (2,830/19.5)

2nd: 347 (4,934/34,000)

1st: 198 (2,816/19.4)

2nd: 344 (4,906/33,800)

Main fuel filter type

Disposable cartridge paper element and water separator

6C – 4 FUEL SYSTEM

GENERAL DESCRIPTION

When working on the fuel system, there are several things to keep in mind:
・ Any time the fuel system is being worked on, disconnect the negative battery cable except for those tests where

battery voltage is required.

・ Always keep a dry chemical (Class B) fire extinguisher near the work area.
・ Replace all pipes with the same pipe and fittings that were removed.

Clean and inspect “O” rings. Replace where required.

・ Always relieve the line pressure before servicing any fuel system components.
・ Do not attempt repairs on the fuel system until you have read the instructions and checked the pictures relating

to that repairs.

FUEL FLOW

The fuel system consists of the fuel tank, the water separator, the fuel filter, the injection pump, and the injection
nozzle.
The fuel from the fuel tank passes through the water separator and the fuel filter where water particles and other
foreign material are removed from the fuel.
Fuel, fed by the injection pump plunger, is delivered to the injection nozzle in the measured volume at the optimum
timing for efficient engine operation.

Except 4JA1TC, 4JH1TC Engine

FUEL SYSTEM 6C – 5

・ The 4JA1TC, 4JH1TC engine are equipped with the electronically controlled fuel injection system. For

information on fuel injection pump maintenance and/or part replacement, contact the Bosch Automotive
Systems Corporation.

・ Contact the Bosch Automotive Systems Corporation for information on 4JA1TC, 4JH1TC engine fuel injection

nozzle maintenance.

For 4JA1TC, 4JH1TC Engine

6C – 6 FUEL SYSTEM

INJECTION PUMP

A Bosch Distributor Type Injection Pump is used. A single reciprocating/revolving plunger delivers the fuel uniformly
to the injection nozzles, regardless of the number of cylinders.
The governor, the injection timer, and the feed pump are all contained in the injection pump housing. The injection
pump is compact, light weight, and provides reliable high-speed operation.
An aneroid compensator is available as an option for vehicles to be operated at high altitudes. It adjusts the fuel and
air mixing ratio.
A boost compensator is installed on turbocharger equipped vehicles.