I recently put a rebuilt powerhead on a 1991 Evinrude 60hp. The motor runs good but turns 6200 RPM's at WOT and when I trim it out she will run near 7000 RPM. I am 4 1/2 hours into the break in period and will not run WOT for more than a minute or so. I have the timing retarded 2 degrees and the...