Page 184 - REPOWER REFERENCE GUIDE (2020)

Manifolds and Elbows with Dry Joint
IMPORTANT: The restrictor end of the gasket must be positioned to the seawater inlet side of the exhaust elbow.

a
a - Full flow passage
b - Restricted flow passage
c - Turbulator oriented up

b

c
31778
Block‑Off Gasket

Models Covered Description
Closed cooled Block‑off gasket
IMPORTANT: On engines without risers, the block‑off gasket must be placed between the exhaust manifold and the exhaust
elbow.

a
a - No opening for coolant flow
b - Turbulator oriented up

b
31779
Installation
IMPORTANT: The correct turbulator gasket must be properly installed to avoid overheating due to insufficient water flow or
coolant loss through exhaust.
IMPORTANT: Refer to the appropriate Mercury MerCruiser Service Manual if exhaust risers are used.
1. Seawater‑cooled models: Apply sealant to threads of pipe plug and install to exhaust manifold.

c a - Exhaust manifold
b b - Pipe plug
c - Sealant applied to threads

a 31780

Tube Ref No. Description Where Used Part No.
Loctite 567 PST Pipe
9 Pipe plug 92-809822
Sealant

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