I was out on the water a couple of days ago after a carb re-build. Everthing was going well for a few hours, then the ski started smoking and mis-firing. Took the ski home and couldn't get it to turn over (like the batery was dead). Just gone out to it tonight and the bilge is full of oil. The tank was half full and now its empty. I took the intake manifold and carbs off and oil came gushing out of the intake ports. Any ideas what could cause this? I can't find anything obvious like split pipes etc 
