i need help. I have a 1988 Johnson 110 vro. I was on the lake today for a final test run. starts great and runs out great but after about 15 min of cruising I stop and check out the cave located on the lake. I start motor back up and take off and its bogging, but, when I trim the motor about halfway up it'll catch up and take off. it never does this when I first start the motor and take off, only after its up to operating temp... any ideas on what to replace or do ive replaces coils plugs and power pack plus gone thru carbs.