How does a jet ski with a four stroke engin work?

Question

How does a jet ski with a four stroke engin work?

Answer 1

Someone with technical expertise can help on how they work.  I sold jet skis for a number of years and if you are looking to purchase maybe I can help with the following.

From a sales point of view jet ski 4-stroke engines have 3-cylinders.  Compared to 2-stroke they run quieter, much smoother, and burn fuel more efficiently.  A huge selling point is you do not mix fuel/oil saving a lot of money on oil alone.

Best units are the SeeDoo's but Yamaha are very good units as well.  Polaris filed bankruptcy in 2007 but some dealers still have in stock for very good prices.

Boat shows are the best places to purchase for deals.  4-strokes are much more desireable.

Answer 2

Engine drives impeller in tunnel full of water in hull. Resulting 'jet' of water produced drives vessel along, Cowling is dropped over back-end of tunnel, redirecting jet forwards, in one quick action, for 'stop' / 'reverse'.

Answer 3

Just like a 2-stroke, but with a 4-stroke engine.

Answer 4

The same way a 2-stroke works except for the 2 extra strokes of course.  4-strokes have been getting much more powerful and are more environmentally friendly than the 2, so they will become the more common engine type used.