Exhaust Extension - Mercury MerCruiser MCM 454 Mag MPI Service Manual

RISERS
IMPORTANT: On elbows with shift plate (MCM only) reinstall shift plate and tighten
fasteners securely, then readjust shift cables as outlined in appropriate Sterndrive
Service Manual.
7. Assemble harness bracket and plastic backup plate, if equipped, using four small
screws.
Drop-Down Bracket For 6 Inch (152 mm) Riser
8. Refill closed cooling system, if equipped. Refer to SECTION 6B - "Closed Cooled
Models."
9. Upon first start-up of engine, check for leaks.

Exhaust Extension

1. Install appropriate exhaust extension for MCM Models with thru prop exhaust, using two
hose clamps at each end.
Typical Exhaust Extension
2. Tighten hose clamps securely.
3. Upon first start-up of engine, check for leaks.
Index
Page 7C-4
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f
c
a - Riser Bracket
b - Harness Plate
c - Back-Up Plate (1)
d - Screws (6) 3/4 In. (19 mm)
e - Nuts (6)
f - Screws (4) 7/8 In. (22 mm)
a - Cut Along Bottom Edge Of Raised Bead For With 3 In. (76 mm) Riser
b - Leave Full Length For Use With 6 In. (152 mm) Riser
a
b
a
b
SERVICE MANUAL NUMBER 23
d
e
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90-861326--1 MARCH 1999