Mercury MerCruiser D2.8L D-Tronic Service Manual page 247

SERVICE MANUAL NUMBER 22
VALVE SEATS
1. Measure exhaust and intake valve seats. Refer to valve seat specifications.
2. If measured values are not as specified repair or replace the valve seats.
Exhaust Valve Seat Specifications
Intake Valve Seat Specifications
90-860074--1 FEBRUARY 2002
c
a - Valve Recession (Max.): 0.03 mm (.001 in.)
b - Head Surface to Seat: 2.05 -2.25 mm (.080 - .088 in.)
c - Counterbore Inner Diameter: (Measurement Not Available At Time Of Printing)
d - Seat Outer Diameter: 39 mm (1.53 in.)
e - Seat Height: 7.90 mm (.311 in.)
f - Seat Width: 2.00 mm (.078 in.)
g - Seat Angle: 60 Degrees
a - Valve Recession (Max.): 0.03 mm (.001 in.)
b - Head Surface to Seat: 2.17 -2.37 mm (.085 - .093 in.)
c - Counterbore Inner Diameter: (Measurement Not Available At Time Of Printing)
d - Seat Outer Diameter: 42 mm (1.653 in.)
e - Seat Height: 7.80 mm (.307 in.)
f - Seat Width: 3.25 mm (.127 in.)
g - Seat Angle: 45 Degrees
a
e
b
50351
ENGINE MECHANICAL
d
g
f
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