Diamond Club

Click to play our newest game, solitaire!

Spade Heart

How to Water Hose Test Polaris Jet Skis

Never run a Polaris jet ski out of the water without a water flush kit.
Comstock/Comstock/Getty Images

The Polaris jet ski, a popular personal watercraft, is a vehicle used in recreational water sport activities. Consisting of a small, boat-like hull and propelled by a powerful engine, jet skis can be seen in the ocean, lakes or rivers. Polaris jet skis often are trailered and used seasonally, and part of the ritual for preparing one for winterizing or storage involves running the engine out of water to test its performance or to flush the cooling system. A Polaris owner can water-test his craft out of water by using a special adaptor kit and a garden hose.

Load your Polaris jet ski on a trailer and place it on a down-slant driveway that has good water drainage. Mix dishwashing soap in a bucket of warm water and use a brush to clean the jet ski's jet nozzle, ride plate, reverse flow gate and the impeller. Remove all weeds, grass and foreign debris. Clean off the exhaust ports. Wipe the engine dry with clean towels. Raise the engine cowl cover by unsnapping the hold-down clips.

Refer to your Polaris service manual for the location of the cooling system drain plugs, then remove them with a socket and wrench. Also check the manual for the location of the water injection port, also called the "flush port." The water injection port will be located on the water bar manifold, which has fins attached to it. It will be equipped with a brass plug. Use a socket or end wrench, depending upon the model, to loosen and remove the brass plug.

Remove the plug fitting on a flush kit adaptor, and screw it into the water injection port with an end wrench. Place the kit hose clamp on the adapter hose and connect the hose to the fitting nipple. Tighten the hose clamp with a slot screwdriver. Turn the on-off valve on the flush kit adaptor to the closed position. Hook a garden hose up to the hose fitting on the flush kit adaptor.

Turn on the garden hose at its source for medium pressure. Turn the engine on and let it idle for about 2 to 5 seconds. Turn on the flush kit adapter valve, allowing water to flow into the engine. Make certain that you see water exiting the exhaust port, cooling port and impeller grate at the rear of the engine. The exhaust water should be mildly warm to the touch.

Examine the performance of the engine while running the flush water through the system. To completely flush the system of salt, dirt and corrosives, let the engine run for approximately 8 minutes. After 8 minutes, turn off the water valve on the flush kit adaptor and let the engine run for 3 to 5 seconds before shutting it off.

Disconnect the flush kit adaptor hose clamp with a screwdriver, then remove the intake flush port adaptor fitting with an end wrench. Insert the intake flush plug and tighten it with a socket and wrench. Replace the drain plugs and tighten them with a socket.

Things You'll Need:

  • Dishwashing soap
  • Bucket
  • Cleaning brush
  • Towels
  • Polaris service manual
  • Socket set (including Allen head)
  • Ratchet wrench
  • End wrenches
  • Polaris flush kit
  • Screwdrivers
  • Garden hose


During the test, you can raise the idle to a slow to medium speed to gauge the engine performance, but do not hold the throttle at medium high or full position. Revving the engine is not recommended with a flush adaptor kit attached.

Our Passtimes