hey ive got a yz450f carbi problems

3 replies to this topic
  • raymond2293

Posted March 12, 2014 - 02:45 AM


Ok its a yz 450f 09, first thought was valves were out because it was backfire when trying to start, valves are to spec so then i thought it was getting to much fuel checked plug out good spark but is dry, the carbi does not squirt fuel when throttled i have no idea with carbis can any one explain why its not squirting fuel into head, pics would be good thanks in advance! =)

  • grayracer513

Posted March 12, 2014 - 07:08 AM


Check that fuel flows from your petcock to the carb.  Remove the bowl plug and be sure there is fuel flowing into the carb as you turn the gas on.


If the carb in fact has fuel in it, then a lack of any accelerator pump squirt is probably due to a faulty pump diaphragm or a clogged discharge nozzle in front of the slide. 

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  • raymond2293

Posted March 12, 2014 - 12:08 PM


Okay thanks its has got fuel in bowl because fuel comes out bottom overflow when throttled,

  • grayracer513

Posted March 12, 2014 - 12:49 PM


Be sure that fuel isn't coming from around the accelerator pump shaft on the right side of the carb.  That would be a definite indication that you have a torn diaphragm.

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