by freddyst » Sun Oct 01, 2006 8:00 am
If you are still having a problem, check you plug coil. Put a new one in and run it, then bring it back. If it looks bent, but not burnt, your head clearance could be the cause. If it looks good, I'd check the bearings and looks for leaks in the fuel system. Are you running 2 tanks? If so, try one tank at a time to see if it might be a tank or a fuel line. Another thing to check is your drive-line. If it binds or your shaft is mis-aligned, this can cause the engine to have problem. Does the engine seem hot when it returns? if so binding of the shaft or low cooling water can be the cause. The last thing I can think of (off hand) is your tune pipe length. If you are running a tune pipe, it may need to be lengthened. In fact, I'd check this first (got my response a little out of order). I race 1/8 scale hydroplanes, with 67 motors, and these are issues that have caused me problems when trying to get a boat 'on the pipe' (full speed). :)