So I have a 86 mercury with a 350 in it last year it was not winterized as well as it could have been I had it running well while out of the water but I put it on the dock and now it is doing many different things at first I replaced the starter because the motor was cranking too slow to start but that did not help it when I start to pump the throttle it comes to a complete stop and once the fuel clears out it cranks slowly again plus spits gas out of the carb next I was told to try some starter fluid in it which did get it running but now it over heats very fast when it runs and it runs very very rough will not idle and backfires out of the carb im being told timing issue but nothing has changed on it since the year before and it had ran perfect every weekend all summer im at the end of my rope with this and if anyone could give some advice as to what I should try next that would be great. Thank you