i had my motor rebuilt last year and it has not been running like it should and i have been trying to figure out why.i have tryed different props and still not like it was before rebuild .So the other day i thought i would get some new plugs and put them in got the plugs today and went to change them out and while i was looking at the old plugs i saw that the plugs that were in the motor were not the same plug i ordered . i know i ordered the right plugs because i looked them up on the link in this forum.Motor calls for ql78yc plug 04 johnson 150 the plugs that were in the motor the dealer put in after rebuild were ql87yc i looked these plugs up and they show they are for a 3 to 3.5 hp motor could this be the cause of the rpms being way low and lose of top speed ?