how fast are you going? it could be sucking in steam. I had that problem with mine until i snorkeled it. You also need to put dielectric grease on all the connections.

 

Mine did the same thing and it was definitely the steam. I checked this by getting my motor warm and then running some water over it. Once it started steaming I revved the motor and it started skipping until the steam was gone. I just finished installing my snorkel yesterday so I'm ready to go give it a try.

 

thanks for the idea. let me know how it works.