head gasket

4 replies to this topic
  • chopp123

Posted February 13, 2011 - 12:20 PM


anybody think its possible to suck the crank case pressure into the cyl throught the head gasket. no matter what i do my bike is poping and backfiring. changed electrical, carb, cant figure it out. has new piston and crank. noticed that some smoke was coming out the vent. wondereing if its sucking and then blowing the crank case pressure out. my head isnt warped eathier. timing is right, im completely lost

  • lumpy790

Posted February 13, 2011 - 12:39 PM


I have herd of a slight exhaust leak at the header/muffler joint causing a back fire popping on decel.

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  • chopp123

Posted February 13, 2011 - 01:45 PM


its not that. im pretty sure im sucking antifreeze and air in that head gasket.must be a shit one. its at any point when i hit the throttle. and its violent. pipe is trying to break apart at the coupling.

  • lumpy790

Posted February 13, 2011 - 03:38 PM


Typically a blown head gasket will push compressed air into the cooling system. An automotive CO2 sniffer will tell you if there is CO2 in the coolant. A coolant pressure test would push coolant into the cylinder.

  • chopp123

Posted February 14, 2011 - 04:16 PM


the dam carb i bought on ebay had the slide upsidedown i dont know how my other motor ran for 2 years with it but that was the whole problem.

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