2002 426 still puffs smoke

2 replies to this topic
  • freestyler727

Posted May 19, 2002 - 12:10 PM


hey guys sorry to bother you again.the symptoms are as follows,cold or warm cosed to 1/4 trottle 2 puffs of back smoke not blue. on the ttrack orsitting in gear and in nuetrel. i tried cleaning all passages venta air filter yes oil level is normal when i first started up it didnt stumble tnen at track it did. wnen i changed spark plug it went away tnen started doing again. yes i tried lowering pilot jet 45 to 42 to 40. it puffed and stumbled at all settings. plot fel screw did not change symtoms. the mid to toprun reak good just in o to1/4 throttle opening.next step replace accel pump diaphram.any ideas? p.s. should the bk mod be done on 2002 model this is a canadian model.spes 150 main 42 pilot 1&3/4 fuel screw.

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  • Mark_Cantrell

Posted May 19, 2002 - 02:33 PM


Your jetting sounds pretty good. Do you have to blip it to get smoke or can you roll it on and get smoke. If only when blipped, it could be the AP, otherwise you may just have to live with it.

If you have a buddy with a Vortex or a 2001 CDI that you can try, see if it is the ignition timing.

Good luck,

  • Mark_Cantrell

Posted May 19, 2002 - 03:16 PM


per your PM, If it only occurs rolling on throttle and not blipping, the AP is probably not a factor. It would be worse blipping.

I am putting my stock CDI back on soon and sending Vortex back to MTRacing for reprogramming. When I get my Vortex back, I'll loan you my stock '01 250F CDI.

Off topic, I had a Mercruiser888 which is based on the old GM small block 305. It smoked awful at the dock. Jet black smoke, until it warmed up. Fooled with carb for hours over a few months. When I adjusted the dwell and timing (until recently boats were just like cars from the '60s), the problem went away. Never really knew what it was but I didn't complain after that.

It will be a few weeks for Vortex to go both ways. In about 2 weeks, PM me with your address. Just remember to send it back.

Good luck,

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