I have a 75hp EFI Yamaha and it has run fine. Yesterday it started and ran fine at about 5000 rpms. Ater 20 minuets of running as I slowed down the engine started to run rough and eventually stalled out. I was not able to immediatly start it but after about 10 minuets it started and ran fine again. At the end of the day as I was pulling into the dock it did the same thing and I noticed what appeared to be a film of gas on the water. Thanks, Any ideas would be appreciated.