Why does my mercruiser 4.3 sputter and backfire after hot after the engine has been running and it is hot, if I slow down and then give it gas again, the engine sputters and backfires. it does not quit. but I have to speed up slowly through the sputtering to get up to cruising speed.

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07 Nov, 2017

  • 73%
    Solved this issue
  • 102min
    Time to fix
  • 58%
    Recommend to DIY
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It sounds like a fuel vapor lock, check that the fuel line to the carb is not coming contact with any metal surfaces of the engine for this will boil the fuel in the line before it enters the carb. If this is the case, just stand the fuel line off from where it is touching. I hope this helps....GOD BLESS....Randy...
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