Polaris 2003 Genesis i Owner's Safety And Maintenance Manual page 57

Engine Break-in Procedure
If the engine is run while the watercraft is in very shallow water,
sand, weeds and debris may be sucked into the jet intake and
could cause damage to the impeller or injury to bystanders.
Ingesting sand into the cooling system will cause the engine to
overheat, which could lead to engine damage.
Whenever starting the engine, always be sure the watercraft is in
water at least two feet (60 cm) deep.
2. Launch the watercraft.
3. Push the rear of the watercraft up and down several times in the
water. Check the throttle for free operation and start the engine. Let
the engine warm up for about a minute before departing.
4. The lowest possible speed should be used for the first five minutes
of operation.
5. Gradually open the throttle to half speed.
6. Vary throttle speeds up to 3/4 speed during the break-in period.
CAUTION
OPERATION
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