Table 5-3. Engine Dimensions and Clearances

TM5-411 0-234-14

TO 40R7-5-7-1

(1) The engine is equipped with adjustable tappets. To make a valve adjustment, remove the valve covers.

Crank the engine over slowly by hand until the left hand intake valve, when facing the flywheel, opens and closes.

Continue about 1/4 turn until the correct timing marks aline. This should place the left hand piston at the top of its

compression stroke, the position it must be in to get proper valve adjustment for the left hand cylinder. Clearances are

shown in Table 5-3. For each valve, the gage should just pass between the valve stem and valve tappet.

Table 5-3. Engine Dimensions and Clearances

All clearances given at room temperature of 700F.

All dimensions in inches unless otherwise specified.

Minimum

Maximum

Valve Tappet to Cylinder Block Clearance ...........................

0.0015 (0.038 mm)

0.0030 (0.08 mm)

Valve Stem in Guide - Intake................................................

0.0010 (0.03 mm)

0.0025 (0.06 mm)

Valve Stem in Guide- Exhaust .............................................

0.0025 (0.06 mm)

0.0040 (0.10 mm)

Valve Seat Interference Width..............................................

1/32 inch (.79 mm)

3/64 inch (1.19 mm)

Valve Face Angle .................................................................

Valve Seat Angle ..................................................................

Valve Interference Angle ......................................................

Crankshaft Main Bearing ......................................................

0.0024 (0.061 mm)

0.0042 (0.10 mm)

Crankshaft End Play.............................................................

0.006 (0.15 mm)

0.012 (0.30 mm)

Camshaft Bearing.................................................................

0.0015 (0.04 mm)

0.0030 (0.08 mm)

Camshaft End Play...............................................................

0.003 (0.08 mm) ---

Rod Bearing (Forged Rod) ...................................................

0.0005 (0.01 mm)

0.0023 (0.06 mm)

Connecting Rod End Play (Ductile Iron)...............................

0.002 (0.05 mm)

0.016 (0.41 mm)

Timing Gear Backlash ..........................................................

0.002 (0.05 mm)

0.003 (0.08 mm)

Oil Pump Gear Backlash ......................................................

0.002 (0.05 mm)

0.005 (0.13 mm)

Piston to Cylinder, Strut Type (Measured below Oil Controlling

Ring - 900 from Pin) Clearance ............................................

0.0025 (0.06 mm)

0.0045 (0.11 mm)

Piston Pin in Piston...............................................................

Thumb Push Fit

Piston Pin in Rod ..................................................................

0.0001 (0.0025 mm)

0.0006 (0.0152 mm)

Piston Ring Gap in Cylinder .................................................

0.010 (0.254 mm)

0.023 (0.584 mm)

Crankshaft Main Bearing Journal - Standard Size ...............

1.9992 (50.779 mm)

2.000 (50.8 mm)

Crankshaft Rod Bearing Journal - Standard Size ................

1.6252 (41.280 mm)

1.6260 (41.300 mm)

Cylinder Bore - Standard Size ..............................................

3.2490 (82.525 mm)

3.2500 (82.550 mm)

Piston Ring Side Clearance..................................................

0.0020 (0.05 mm)

0.0080 (0.20 mm)

(2) To correct the valve clearance, turn the adjusting screw as needed to obtain the right clearance. The screw

is self-locking.

(3) To adjust the valves on the right hand cylinder, crank the engine over one complete revolution and again line

up the correct timing marks. Then follow the adjustment given for the valves of the left hand cylinder.

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