I have done 6 hrs on a fully recon 90HP 'rude on a 17'6" lightening. running a 25:1 mix (50:1 VRO & 50:1 premix) as per mechanics instuction to 8hrs. I experienced a sudden drop in revs from 3500 to 2000rpm. The motor idles sweet but under load won't top 2000rpm. The plugs are very oily. Can...
