| Clearance | A.C. generator maximum permissible run-out at rotor bearing | 0.010 | in. | |
| Clearance | Camshaft bearing journal dia. #1 | 1.8715 - 1.8725 | in. | |
| Clearance | Camshaft bearing journal dia. #2 | 1.7457 - 1.7465 | in. | |
| Clearance | Camshaft bearing journal dia. #3 | 1.2465 - 1.2475 | in. | |
| Clearance | Camshaft bushing #2 | 0.003 - 0.0045 | in. | |
| Clearance | Camshaft bushings #1 and 3 | 0.002 - 0.004 | in. | |
| Clearance | Camshaft end play | 0.0005 - 0.0015 | in. | |
| Clearance | Connecting rod bearing | 0.0002 - 0.0022 | in. | desired .001 in. |
| Clearance | Connecting rod side play | 0.006 - 0.010 | in. | |
| Clearance | Crankshaft main bearing | 0.0002 - 0.0024 | in. | desired .001 in. |
| Clearance | Crankshaft main bearing journal size | 2.249 - 2.250 | in. | |
| Clearance | Crankshaft rod bearing journal size | 1.9365 - 1.9375 | in. | |
| Clearance | Cylinder bore size | 3.4375 - 3.4395 | in. | |
| Clearance | Fan and generator belt play | 3/4 to 1 | in. | pressure applied midway between pulleys |
| Clearance | Piston pin in rod bushing | 0.0002 - 0.0006 | in. | desired .0004 in. |
| Clearance | Valve stem clearance in guide - exhaust | 0.0045 | in. | desired |
| Clearance | Valve stem clearance in guide - intake | 0.0015 | in. | desired |
| Gap | Distributor points gap - 12 volt battery ignition | 0.020 | in. | |
| Gap | Magneto points gap - Fairbanks Morse | 0.015 | in. | |
| Gap | Magneto points gap - WICO | 0.020 | in. | Spec A plants only |
| Gap | Ring gap, 3 top grooves | 0.007 - 0.017 | in. | |
| Gap | Ring gap, bottom groove | 0.007 - 0.017 | in. | |
| Gap | Spark plug gap - gaseous fuel (LPG or natural gas) | 0.015 - 0.018 | in. | when necessary to aid starting |
| Gap | Spark plug gap - gasoline fuel operation | 0.025 | in. | |
| Injection timing | Ignition timing | 17 | degrees advance | at cranking speed |
| Other | Brush spring tension | 9 - 13 | ounces | |
| Other | Ensign atmospheric regulator maximum line pressure | 8 | inches water column | |
| Other | Firing order | 1-3-4-2 | | |
| Other | Valve seat angle - exhaust | 45 | degrees | |
| Other | Valve seat angle - intake | 30 | degrees | |
| Pressure | Battery electrolyte specific gravity (normal full charge) | 1.275 | | reduce to 1.225 for ambient above 90 F |
| Pressure | Garretson regulator lock-off pressure | 4 | ounces (7 in. water column) | incoming supply 2 to 4 ounces |
| Pressure | Low oil pressure switch cut-off | approximately 6 | pounds | |
| Pressure | Oil pressure at 1800 rpm | 20 - 30 | psi | engine oil hot, governed speed |
| Temperature | Coolant temperature | 150 - 180 | degrees F (65 to 82 C) | operating |
| Temperature | High water temperature switch setting (early adjustable models) | 205 | degrees F | lower 3 degrees F per 1000 ft above sea level |
| Temperature | High water temperature switch setting (later non-adjusting models) | 202 | degrees F | factory set |
| Torque | Cylinder head - 7/16 in. | 70 - 75 | lbs. ft. | |
| Torque | Cylinder head nut torque | 80 | lbs. ft. | |
| Torque | Flywheel - 3/8 in. | 35 - 40 | lbs. ft. | |
| Torque | Gear cover, water pump, front and rear end plates, oil pan - 5/16 in. | 15 - 20 | lbs. ft. | |
| Torque | Main bearing caps and connecting rods 3/8 in. | 35 - 40 | lbs. ft. | |
| Torque | Manifolds - 3/8 in. | 25 - 30 | lbs. ft. | |
| Valve clearance | Valve tappets - exhaust | 0.014 | in. | warm engine, preferably idling |
| Valve clearance | Valve tappets - intake | 0.014 | in. | warm engine, preferably idling |
| Voltage | Battery charge rate | 2 - 20 | amperes | depending on battery charge condition |