I have a 1985 Johnson 120(v4 with v6 gearcase) with a 14 1/2 x 20 stainless raker prop. The boat is a 1650 procraft. I have replaced the vro pump(took off), the tachometer and regulator rectifier. At wot it is turning 3200-3400 rpms. It is very slow planing out. The motor checks out good on the...