I have an old Slickcraft Powered with Twin 1989 Pleasurecraft I/O's. Basically this is a 4 cly 140 HP engine a Velvet Drive Transmission and lastly a Pleasurecraft Outdrive. <br />PROBLEM.... The Port transmission shifts in and out of forward and reverse fine. But when it gets to about 3200 RPM's it starts to slip and over rev. The oil is full and clean in the Trans. Linkage appears to shift fine Any Suggestions?