Regal 53 SC Owner's Manual page 232

ZEUS EXHAUST RELIEF SEACOCK
SEACOCK
CLOSED
On the aft end of the Zeus propulsion pod is a seacock.
Before starting the engines check to see that the Zeus pro-
pulsion exhaust relief seacock is in the "open" position
as seen in the right photo above. The handle should be in
a vertical position which permits excess engine seawater
to exit through the cooler and the exhaust manifold. This
system assists in cooling the hydraulic valve system by
sending exhaust seawater through a heat exchanger and
then out through the drive unit. It also relieves pressure
in the exhaust system.
CAUTION
!
TO AVOID POSSIBLE DAMAGE DUE TO
EXCESSIVE EXHAUST BACK PRESSURE
MAKE SURE THE EXHAUST RELIEF
SEACOCK IS IN THE OPEN POSITION.
Engine & Controls
SEACOCK
OPEN
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