mercury 135 bogs and (pee stream) pulses

[twostroker]

hi i have a older mercury 135 with 3 carbs that has issues. a mechanic put on a new powerhead 2 years ago and it had nothing but trouble since. what it does now - when its cold it has just enough power to get it on a plane and when it warms up it wont even do that. and the (pee) stream out of the engine kinda pulses erradically as if maybe air bubbles are comming through? its not a fuel issue because i rebuilt the carbs and hooked up a seperate fuel supply and no difference. also has new fuel pump. and all new stuff under the flywheel. thanks in advance for any advice