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Old 10-13-2018, 04:25 AM
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1QwkSport2.5r
 
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Join Date: Oct 2006
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It sounds like the idle mixture is too rich and the high speed (main needle) is too lean. I would double check that the idle gap is no larger than 0.7mm and set your high speed needle 1 full turn richer and lean the idle speed 1/8 turn. Replace the glow plug with a new one - medium heat range long reach plugs are best. Start the engine, warm it up for one tank of fuel. If it’s real slow to rev and real Smokey, lean the idle needle 1/16 turn at a time until it will drive around cleanly but still a little slow and Smokey. Fill the tank back up and get the high speed set. Do a full throttle pass and note how the engine sounds. If it revs slow and Smokey, lean the high speed 1/16th turn and do another WOT pass. Keep doing this until it revs up and up and up clean and smooth. Once it does, set the idle mixture needle so it will idle for 20 seconds. Now punch it to WOT. It should launch and rev up a little slow at first, real Smokey and burbly, but it should clean out and not flame out. If it flames out (quits), the idle is too rich. Lean 1/16th turn, run a WOT pass, and repeat the idle for 15-20 seconds. Keep doing this until it will rev from idle to WOT without quitting.