How do find out what engines are in my two jetski's?

Question

i have a 1996 three person yamhama and a 1994 two person seadoo.

Answer 1

I'm with ozzzz. Look on the engine. It's a small silver plate(may have some coloring on it). It should show make model size of motor, etc.

Answer 2

If the Yamaha has three spark plugs, probably an 1100.  If only two, likely a 700 or 760.

Look at the color of the Seadoo.  Yello would most likely be a 580.  White is probably a 720.

Answer 3

Look on the engines, there should be an identification plate with the engine model, serial number, etc.