I have a 1988 SeaRay 18 OB with a 135 HP Mercury (SeaRay) V6 outboard.
I purchased the boat new and except for a stator going bad a few years
ago it has run fine. We used to do alot of skiing and it would always
pull a skier out of the water with no problem. Last weekend I tried
pulling a few skiers and the boat had a very difficult time getting
them out of the water. The boat seems to idle fine, normal
acceleration seems fine, top end seems fine, but the engine seemed to
have no power when pulling a skier out of the water. I had a new set
of plugs with me so I replaced the plugs but it made no difference.

I checked the compression last night and found all the cylinders to be
between 90 and 100 PSI. The plugs all looked ok.

Would anyone have any suggestions as to what I could possibly look
for, or where to start the trouble shooting process?

Thanks