Isuzu L Series - Mechanical Specifications

V. Engine Repair Specifications – 4L
U L-Series Diesel 33
Mechanical Specifications
Cylinder Head/ Valve Train Standard Service Limit
Valve Clearance¬ 0.40 mm/ 0.01575 in ------------------------------------
Cylinder Head Warpage- 0.075 mm/ 0.0029 in 0.15 mm/ 0.0059 in
Cylinder Head Height ® 63.9 mm/ 2.515 in 64.1 mm/ 2.523 in
Valve Depression ¯ 0.7 mm/ 0.0276 in 1.2 mm/ 0.0427 in
Hot Plug Depression 0.05 mm/ 0.002 in 0.05 mm/ 0.002 in
Valve Margin Thickness ° 1.0 mm/03937 in .7 mm/.0276 in
Valve Stem Diameter 7.0 mm/ .2756 in (Int.)
7.0 mm/ .2756 in (Exh.)
6.85 mm/ .2697 (Int.)
6.80 mm/ .2677 (Int.)
Valve Spring Installed Height 29.9 mm -------------------------------------
Valve Seat Angle
45°
¬ Valve adjustment clearances are established cold.
- Maximum grinding allowance is 0.3 mm/ 0.0118 in
® Measurement is established by measuring from the head’s sealing surface to the rocker bracket
surface area.
¯ Dimension taken from the cylinder head surface to the top of the valves
° Specification is for both intake and exhaust valves.
Short Block Specifications Standard Service Limit
Main Bearing Bore Diameter 55.98 mm/ 2.2039 in 56.0 mm/ 2.2047in
Cylinder Block Height
4LB1
4LC1/4LD1
280.94 mm/ 11.060 in
307.94 mm/ 12.123 in
281.06 mm/ 11.065 in
308.06 mm/ 12.128 in
Main Bearing Journal Diameter
4LB1/4LC1
4LD1
56.0 mm/ 2.2047 in
60.0 mm/ 2.3622 in
55.86 mm/ 2.1992 in
59.86 mm/ 2.3567 in
Crank Pin Diameter
4LB1
4LC1
4LE1
43.0 mm/ 1.6929 in
46.0 mm/ 1.8110 in
49.0 mm/ 1.9291 in
42.87 mm/ 1.6878 in
45.87 mm/ 1.8059 in
48.87 mm/ 1.9240 in
Piston Protrusion .400 mm/ .0158 in --------------------------------
Piston to Cylinder Clearance 0.015-.035 mm/ 0.0006-.0014 in
Main Bearing Clearance 0.029-0.072 mm/ 0.0011-
0.0028 in
.0127 mm/ 0.005in
Connecting Rod Bearing Clearance 0.035 mm-0.073 mm/
0.0014-0.0029 in
0.10 mm/ 0.0039 in
Crank Gear/ Idler Gear Backlash 0.04 mm/ 0.0017 in 0.2 mm/ 0.0079 in
Cam Gear/ Idler Backlash 0.03 mm/ 0.0012 in 0.2 mm/ 0.0079 in
Crankshaft End Play 0.058-.208 mm
(0.0023-0.0082 in)
0.30 mm/ 0.0118 in