SECTION 20A: Diesel Diagnosis—7.3L IDI Engine

7.3L Naturally-Aspirated Diesel Engine Performance Specifications
Engine ModelA-185, A-166
Number of Cylinders8
Bore104.39 mm (4.11 inch)
Stroke106.20 mm (4.19 inch)
Displacement7.3 Liters (444 cu inch)
Crankshaft Rotation (Viewed from
Flywheel End of Engine)
Compression Ratio21.5:1
Firing Order1-2-7-3-4-5-6-8
Idle Speed (No Load)*650 rpm ± 50 rpm
Governor Speed (No Load)3660 ± 50 rpm
Governor Speed (Full Load Rated)3000 rpm
Timing (Dynamic)8.5 ± 2 Degrees BTDC
Injection PumpStanadyne DB-2
Injection Nozzle 
  Opening Pressure (New)12,928 ± 517 kPa (1,875 ± 75 psi)
  Opening Pressure (Minimum)9,825 kPa (1,425 psi)
Crankcase Pressure-No Load (Maximum)20 kPa (6 in-H2O) @ 3300 rpm
Fuel Pressure (Filter Inlet)14 kPa (2 psi) @ idle
Fuel Pressure (Filter Outlet)7 kPa (1 psi) @ 3300 rpm
Fuel Pump Suction20 kPa (6 in. H2O) @ 3300 rpm
Fuel Return Line Pressure14 kPa (2 psi) @ 3300 rpm
Valve Lifter0
Valve Lash
Engine Lube Oil Pressure
Low Idle, Minimum
69 kPa (10 psi)
(Engine at Operating Temperature)276-482 kPa (40-70 psi)
Crankcase Capacity (Without Filter)8.5 L (9 qt.)
Crankcase Capacity (With Filter)9.5 L (10 qt.)
Thermostat Opening Temperature89°C (192°F)
* Manual transmission in NEUTRAL position. Automatic transmission in DRIVE position.