Mercury MerCruiser MCM 454 Mag MPI Service Manual page 219

SERVICE MANUAL NUMBER 23
7.4L MPI (L-29) Engine Specifications (Continued)
VALVE SYSTEM
CYLINDER HEAD
Index
90-861326--1 MARCH 1999
Downloaded from https://needmanual.com/
MODEL
Lifter
Rocker Arm Ratio
Face Angle (Intake & Exhaust)
Seat Angle (Intake & Exhaust)
Seat Runout (Intake & Exhaust)
Seat Width Seat Width
Production Production
Stem
Clearance
Service Service
Valve Lash (Intake and Exhaust)
MODEL
Gasket Surface Flatness
MODEL
Lobe Lift Lobe Lift .020 (0.051) 020 (0 051)
Duration at .050 In. (1.27mm) Cam Lift Duration at 050 In (1 27mm) Cam Lift
Journal Diameter
Journal Out Of Round
Camshaft Runout
Timing Chain Deflection
Hydraulic Roller
.002 (0.05) Max
Intake .0300-.0600 (0.7620-1.5240)
Exhaust .0600-.0950 (1.5240-2.4130)
Intake .0010-.0029 (0.0254-0.0737)
Exhaust .0012-.0031 (0.0300-0.0787)
Intake
Exhaust
.004 (0.1016) Overall Maximum .003
(0.076) within a 6 in. (152 mm) Span
Exhaust
Intake
Exhaust
Intake
454 CID (7.4L) / 502 CID (8.2L)
7.4L
1.70 to 1
45
46
.0037 (0.0939)
.0049 (0.1244)
Net Lash
7.4L
7.4L
.284 (7.214)
.282 (7.163)
209
209
1.9482-1.9492
(49.485-49.509)
.001 (0.025) Max
.002 (0.051) Max
.375 (9.5) from taut position
[Total .75 (19)]
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