i have a long story but will make it short 1973 135 evinrude 4cyl. have a back fire at an idle out the exshust only it is a a boat shop now they first said it was the reed values ok change them then carbs, then stator power pack and coils don't know which one but need to replace all four ok now they are telling me that the engine is just worn out and it can't mix the fuel properly and that the exshaust is cloged from the fuel now it has good comp and it dose not bleed down fast hold for at least 2 miniuntes. i'm just sick of spending money and still have the same problem other boat shops around town will not work on it untill boating season is over new makes money old don't what could it be bad exshaust problem or what boat runs fine after you get to plain let it idle and it pops and dies hard to start after and most of the time even when it hot you must choke it any help would be nice
