I have a 1988 35hp as the title suggests it backfired and wont start anymore. Well not for more than a few seconds. It cut out on me in the middle of the lake a few days ago and stranded me. Got back to my dock and went to a local mercury specialist and brought the carb to him to look at. He said the carb looked fine and it was probably a Fuel pump diaphragm. Bought the kit and replaced the gasket and diaphragm in the order they came off(old one had some tears in it). Cranked it over and it started right up and idled better than it ever has while iv owned it, for 30 seconds. Then it idled way up, backfired, and stopped running no matter how much i manipulated the butterfly. Primer bulb gets hard and the plugs look fine too. At least they look like 2 stroke spark plugs. Not overly wet or fouled and not dry either. One last symptom i noticed is smoke coming from under the cowl near the mounts after it ran for a few seconds. And im at a total loss as to what that can be. It doesnt sound like a powerhead gasket to me. Any help would be appreciated because id like to have a boat to use on the rest of my vacation if possible. Thanks!
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