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 book calls for 5-6K RPM at WOT. The motor is on a 91 Bass Tracker TX17 original and the prop is a 17 pitch. I don't know what the motor did before as I bought the boat with a blown motor. Any suggestions on what might be the cause and do I need to go up to an 18 pitch or higher prop? PS: Excessive RPM's were not the cause of the blown motor previous to rebuild.
Thanks Joe, All I have is a dial that reads 4 , 8 , 12 and 16. I also have a potentiometer dial that is for calibration on the back of the Tach. Is there a way to calibrate it?
Bill..... I have no idea as to what that tachometer is or if it's designed to work with that engine. The omc engines are designed so that the charging system operates the tachometer by putting out a six (6) pulse signal.Hopefully someone else will jump in here that has knowledge of the tachometer you have.