I have a mid-80s vintage Evinrude 70 VRO and starting last season I had problems going to WOT from idle. Usually fine out of the gate but seems as soon as the engine is warm (i.e. after one tube/ski) it just stalls when you punch it. I have purchased carb kits for a rebuild but don't really want to get into that until the end of the season. Is there anything else I should be checking for?