3.9L Isuzu 4BD1T

Isuzu 4BD1T Diesel Specs (1986 - 1991)

The Isuzu 4BD1T is a direct injection, turbocharged diesel engine with a 3.9L displacement. It is found in 1986 to 1991 model year Isuzu NPR and Chevrolet W4500 commercial vehicles in addition to global on-highway, marine, and industrial applications. It is a turbocharged version of the naturally aspirated 4BD1, offering significant more power and less power loss at higher altitudes. Possibly the most common power rating was a 135 horsepower variant rated at a peak 243 lb-ft, although the engine series was produced many varieties depending on application and model year.

3.9L Isuzu 4BD1T Specs

Engine Isuzu 3.9L 4BD1-T (AKA QD100T)
Manufacturer Isuzu Motors Ltd
Applications 1986 - 1991 Isuzu NPR/Chevrolet W4500
Type 4 stroke direct injection diesel
Configuration Inline 4 cylinder (I-4/L-4)
Displacement 3.856 liters, 236.08 CID
Firing Order 1 - 3 - 4 - 2
Engine Block Cast iron, dry type cylinder liner
Cylinder Head Cast iron
Compression Ratio 17.5 : 1
Cylinder Bore 4.02 in (102 mm)
Cylinder Stroke 4.65 in (118 mm)
Valvetrain OHV, solid lifter camshaft
Injection Mechanical inline injection pump, direct injection
Aspiration Turbocharged, IHI 6HB6 or Garrett T25 models
Engine Dimensions (approx.) Length: 31.3 inches
Width: 27.8 inches
Height: 29.7 inches
Engine Weight (approx) ~770 lbs
Horsepower up to 135 hp @ 3,000 rpm
(varies by application, 135 hp rating common for Isuzu NPR/Chevrolet W4 applications)
Torque up to 243 lb-ft @ 1,800 rpm (varies by application)
Idle Speed ~ 650 rpm
Max Engine Speed ~ 3,500 rpm