I have what appears to be a late 70's Evinrude 70 hp outboard. It will run great on the muffs or in a barrel without a load, but with a load i can open the throttle all the way and it takes longer than usual to get on plane, sometimes with a sputter and then it sounds like it catches up. It may plane eventually depending upon the weight in the boat. With only a few people and some tackle it picks up quickly sometimes, but sometimes it still drags or hesitates. I have taken the carbs apart and cleaned them and checked for sticking valves and it ran great right after that but then went back to its loss of power. Compression checked at 100 psi on all 3 cyl. Once on plane it runs great, but it seems to be lagging to get there. I do smell excess fuel and it leaves a little in the water when sitting still. I also see quite a bit of excess in the breather box when i take it apart. I have done a few backyard tests to try and figure out if it is a carb or powerhead issue and from what i have been told it sounds like carbs. Any ideas from anyone with more experience would be greatly appreciated. I am tired of taking the carbs on and off and not getting results i need. I have rebuilt them already and was thinking about replacing them, but if it is a powerhead issue there is no reason. Thanks!