00 yz426f 2 lean..

4 replies to this topic
  • Ealum450

Posted December 08, 2009 - 12:21 PM


im working on a 426 and its lean as heck.... It pops a bit, spark plug is white..... ouch!! just adjusted the valves, no exhuast leaks anywhere, the air screw is out 2.5 turns, 165 main jet in it, its not the TPS, or nuetral switch..... But however the slide in the carb, all of the teflon coating is wore off and i think its causing it to suck air and the thottle hangs a lil bit after you let off of it.... It takes a second to idle back down after you let off the throttle..... just seeing if anyone has had this problem.... thanks for your time and any help would be appreciated....

  • grayracer513

Posted December 08, 2009 - 01:31 PM


The spark plug doesn't mean much, unless you run leaded gas. A hanging idle indicates a lean condition, but that can be caused also by tight intake valves.

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  • Ealum450

Posted December 08, 2009 - 02:00 PM


well im using 93 octane, the valves are in spec... im just wondering has anyone replaced there slide because of this problem.. i am going to... its pretty pricey, but i know that will be one more thing that i know it wouldnt be... besides, the slide is straight wore out....

  • Krannie McKranface

Posted December 08, 2009 - 06:22 PM


I wouldnt' worry about the slide, but the slide plates are known to leak, and cause 'hanging idle'.

Have you inpected the hotstart plunger? They hang up making it run lean too.

  • Ealum450

Posted December 08, 2009 - 06:30 PM


yes sir i have checked the hotstart plunger.... the slide plate is what im talking about, the coating is gone and its just metal 2 metal rubbing so im sure thats what my problems is...... thanks for everyones input...

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