BOMBARDIER SEA-DOO GS 5626 1998, Shop Manual

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Section 05 COOLING SYSTEM
Subsection 02 (CIRCUIT, COMPONENTS AND CARE)
05-02-5
CIRCUIT
717 and 787 Engines
A Serial Cooling System is utilized on the 717 and
787 engines, which offers an efficient cooling of
the combustion chamber to prevent the possibili-
ties of detonation.
The water supply is taken from a pressurized area
in the jet pump between the impeller and venturi.
Water enters the cylinder head, cooling the com-
bustion chamber to prevent detonations. Then,
water exits cylinder head toward tuned pipe.
1. Cylinder head cover
2. Fresh water from jet pump
3. Water exiting head assembly to tuned pipe, exhaust manifold and
cylinders
4. Water from cylinder water jackets exiting engine
The tuned pipe and exhaust manifold are de-
signed with a double wall to allow water circula-
tion.
Water is pre-heated by the exhaust system before
entering the cylinder cooling jackets.
Water enters cylinder cooling jacket through pas-
sages located below exhaust ports from tuned
pipe.
1. Water passages
No water enters crankcase.
When engine is running, water must flow from
bleed outlet indicating that water circulates.
For a minimum back pressure in the exhaust, en-
gine water outlet hose is not connected to the ex-
haust. It has its own outlet at the rear of the hull.
TYPICAL
1. Engine water outlet hose
-
CAUTION
All hoses and fittings of the cooling system
have calibrated inside diameters to assure
proper cooling of the engine. Always replace
using appropriate Bombardier part number.
F01E1LA
2 3
1
4
-
CAUTION
When investigating for no water flow in the
cooling system, check all elbows and straight
fittings as well as all hoses for blockage.
F01D7HB
1
F01E1GA
1