Isuzu 4ja1 User Manual

6A – 76 ENGINE MECHANICAL
Tappet Outside Diameter
Measure the tappet outside diameter with a micrometer.
If the measured value is less than the specified limit, the tappet
must be replaced.
T
appet Outside Diameter mm (in)
Standard Limit
12.97 - 12.99
(0.510 - 0.511)
12.95 (0.510)
T
appet and Cylinder Body Clearance
mm (in)
Standard Limit
0.01 - 0.046
(0.0004 - 0.0018)
0.10 (0.004)
Push Rod Curvature
1. Lay the push rod on a surface plate.
2. Roll the push rod along the surface plate and measure the
push rod curvature with a thickness gauge.
If the measured value exceeds the specified limit, the push
rod must be replaced.
Pushrod Curvature mm (in)
Limit
0.3 (0.012)
3. Visually inspect both ends of the push rod for excessive
wear and damage. The push rod must be replaced if these
conditions are discovered during inspection.
014RY00029
012LX014
014RY00031

Isuzu 4ja1 Specifications

General

Fuel Type	Diesel
Cylinder Configuration	Inline-4
Fuel System	Indirect Injection
Aspiration	Naturally Aspirated
Compression Ratio	21.5:1
Cooling System	Water-cooled
Engine Type	Diesel
Displacement	2.5 L (2499 cc)
Bore x Stroke	93 mm x 92 mm
Maximum Torque	176 Nm (130 lb-ft) at 2000 rpm
Valvetrain	Overhead Valve (OHV)