ScrichtonT

Hi Guys/Gals.  Hoping you can shorten a frustrating experience.  Purchased the above referenced boat 30 days ago.  Main motivation was the newer engine (787) that was still under warranty for a couple more weeks.  Have all the paperwork.  Have previously owned Sea Rayder and Challenger 1800.  Have basic knowledge but not a motorhead, or techie.

First time out boat ran great, (though getting out of the hole was labored).  Two hours into first run, she fairly quickly fell off plane, and struggled with mis-firing and RPMs fluctuating to 4500 tops, often lower.  Figured wear ring, since she struggled out of the hole.  Took it apart.  Sure enough, some good gouges and a less than perfect prop.  Took the pump to my local guy and he put new ring in.  First sea trial, she climbed out of the hole much better and ran 500rpm lower at same speed.  Thought it was fixed.  15 min into run, (engine warmed up?), she fell off plane again, and would not run above 3500-4000 rpm.  Took to my local guy again.  Checked compression.  Good!  He made no commitments, but thought most likely suspect was coil.  Replaced.  Checked spark.  Checked Plugs, a little fouled but nothing serious.  Tested today. Now would not even get up on plane cold.  Still won't run above 3500-4000.  Although ran notably smoother.  Full rev on trailer if in gear..     

Have thought about carb, but doesn't make sense that it ran smooth and then just fell of plane with no indication of trouble.  But then, that's why I am here.  Talk to me please.  Please us KISS principle as I qualify.