Mack E7 Service Manual page 113

5-101.bk Page 23 Friday, March 17, 2006 11:05 AM
Refer to Figure 5-24.
The cast iron cylinder head is constructed using a
special iron alloy. The head contains cored inlet,
exhaust and coolant passages, drilled oil
passages, replaceable inlet and exhaust guides
and seats, various drilled passages and tapped
holes. Each cylinder head covers three cylinders
200 BENCH PROCEDURES
1989/1990 E7 COMBUSTION SYSTEM
ORIGINAL SWIRL
LEVEL
1991 AND LATER E7 COMBUSTION SYSTEM
INCREASED SWIRL
LEVEL
Figure 5-23 — Combustion Chamber Design
6-HOLE NOZZLE
TIPS
8-HOLE VCO
NOZZLE TIPS
and has two inlet and two exhaust valves per
cylinder. Circular grooves correspond with the fire
ring bead on cylinder sleeves. This design sets
the fire ring over the liner, the lip and into groove
of the cylinder head while providing a positive
combustion pressure seal. Use a rotary brass-
wire brush to clean the circular groove.
200285a
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