Kawasaki Jet ski performance, Repair &  Maintenance 

Kawi performance

Engine Maintenance and Longevity 

There is a lot of debate over the brand of oil and grade as well. We highly recommend staying away from any conventional motor oil or blend. These oils burn much easier and loose their properties faster. There are two grades we recommend: 10W-40, 15W-50 or 20W-50. 10W-40 is best in cold climates where the water temperature does not go over 70F. The 15W-50 and 20W-50 is the best for most warmer climates since it handles the heat much better, stays relatively thick at higher temperatures and has a higher shear strength. We recommend the thicker oil for all climates below Canada if water temperature hits 80-85+. As for type, we recommend a fully synthetic only. Any top brand motor oil with high anti-wear additives. Royal purple, Motul, Amzoil, Mobil1 (Racing oil), make sure to check for additives. Standard synthetic Mobil 1 DOES NOT have the upper end additives for this engine! This can be marine or automotive oil. Please do not use motorcycle oil, this has clutch additives that you do not want. We use Valvoline VR1 20W-50 Full Synthetic in all of our machines or a combination of 10W-30 and 20W-50 which is about a 15W-40. This oil can handle full throttle all day long (Please make sure to let it warm up first) and shows little to no tappet wear as compared to the Mobil 1 which has much less wear additives if any. These racing oils also contains an anti-foam additive so that the oil does not get as foamy at high rpm. Kawasaki OEM oil is conventional, which has these properties as well.

Bearings To Replace

Here is something that not many shops if any will share with you, but we want customers to have a trouble free and long ski life! On an ultra the below is key for a healthy engine. Please note that due to the supercharger ALL Ultra engines really do not last more than 200-250 hours. We highly recommend refreshing the engine before this time comes to prevent any engine failures. We have tested and tested and have concluded the biggest wear item is the oil pump, which is also the heart of the engine. As the engine wears, so does the pump. As much as you can try to prevent it, this will happen. The pump is cast aluminum with a hardened steel rotor. When small debris get sucked up, it scours the aluminum and steel as it rotates. Over time the scoring gets worse and worse and oil pressure/ volume keeps on dropping. Engine wear accelerates and I am sure you know the result.

• Replace pump bearings and seals seasonally
• Replace supercharger idler bearing seasonally or twice a season for the 300/310's
• Rebuild 250/260 superchargers seasonally or every 100 hours
• Replace drive shaft carriage bearings and seals every season or 2 seasons
• Replace output cover bearing every 3 seasons

Oil Changes

There is a lot of information whether true or false about oil changes and what oil to use. Many people swear by Kawasaki oil, many swear by Yamaha oil and so on. After tons and tons of testing and countless oil changes, we will give you our best recommendation for oil change intervals and what oil to use! The Kawasaki Ultra is a race machine on the water and needs to be treated as such. We recommend oil change intervals of 15 hours on a recreational machine and 10 on a race machine. Reason being is heat and blow by. The oil gets extremely hot from the stresses in these engines and does start to burn very quickly, burning is very bad and degrades the oils properties. Going over 15 hours on a recreational machine increases the buildup of sludge and as the oil burns it will loose its main purpose as a lubricant. Oil should be changed with a new filter and new set of plus. ANY MACHINE MUST USE ANTI-SIEZE ON PLUGS!

What type of oil?