John Deere stx38 - Manual (Page 36)

3 - 4
4/23/97
SPECIFICATIONS ENGINE
TEST AND ADJUSTMENT SPECIFICATIONS
Engine:
Valve Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . None (hydraulic lifters)
Oil Pressure (Minimum at 1250 rpm) . . . . . . . . . . . . . . . . . . . . . . . . . . 124 kPa (18 psi)
Crankcase Vacuum (Minimum At Operating Temp.) . . . 25 mm (1 in.) Water Movement
Automatic Compression Release Minimum Lift (Engine Cold) . . . . . . 0.25 mm (0.01 in.)
Fuel/Air System:
Carburetor Slow Idle Mixture Screw Initial Setting . . . . . . Lightly Seat, Then 1 Turn Out
Slow Idle Speed—Domestic and Export . . . . . . . . . . . . . . . . . . . . . . . . . . 1650 ±75 rpm
Fast Idle Speed—Domestic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3350 ±50 rpm
Fast Idle Speed—Export . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3000 ±50 rpm
REPAIR SPECIFICATIONS
Cylinder Head:
Cylinder Head Flatness (Maximum Warpage) . . . . . . . . . . . . . . . . 0.076 mm (0.003 in.)
Push Rod:
Maximum Bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.76 mm (0.030 in.)
Valves and Valve Lifters:
Hydraulic Lifter Clearance . . . . . . . . . . . . . . . 0.0124—0.0501 mm (0.0005—0.0020 in.)
Intake Valve-to-Guide Clearance . . . . . . . . . . . 0.038—0.076 mm (0.0015—0.0030 in.)
Intake Valve Stem OD. . . . . . . . . . . . . . . . . . . . . . . . 6.982—7.000 (0.2749—0.2756 in.)
Exhaust Valve Stem OD . . . . . . . . . . . . . . . . . . . . . . . . 6.970—6.988 (0.2744—0.2751)
Exhaust Valve-to-Guide Clearance . . . . . . . . . . 0.050—0.088 mm (0.0020—0.0035 in.)
Intake Valve Guide ID:
New . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.038—7.058 mm (0.2771—0.2779 in.)
Maximum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.134 mm (0.2809 in.)
Exhaust Valve Guide ID:
New . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.038—7.058 mm (0.2771—0.2779 in.)
Maximum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.159 mm (0.2819 in.)
Valve Guide Reamer:
Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.048 mm (0.2775 in.)
Oversize (0.25 mm). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.298 mm (0.2873 in.)
Intake Valve Lift (Minimum—Engine Cold) . . . . . . . . . . . . . . . . . . . . 8.96 mm (0.353 in.)
Exhaust Valve Lift (Minimum—Engine Cold) . . . . . . . . . . . . . . . . . . 9.14 mm (0.360 in.)
Valve Face Angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45°
Valve Seat Angle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44.5