I think I've gone full stupid and can't get my 60 to pass emissions. Was high CO, so I need to lean. Can't remember if turning mixture screw in or out to lean??? I want to think turning screw in leans...Correct? Also is there any relation to how much fuel is in sight glass to lean rich status?
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fuel in bowl should be half full- or empty...
mix screw turns IN to LEAN/// OUT to RICH. turn it in gently till it just touches bottom- do not torque it into its seat.I like to back mine out about 4 full turns, back off the idle speed screw till it's just touching the plate, then choke it and start it and let it warm up. once warm, slowly open the choke- if your idle speed screw is too far out, you might need to close the choke real quick to keep the truck running, then add a little more idle speed screw just enough to keep it running slowly without the choke. (about 450-550 rpm) once it'll run without choke, set speed to about 625, then slowly turn mix screw IN till the idle speed drops. (turn screw, wait for idle to respond, listen for change in speed; repeat) once you notice a drop in idle, turn the mix screw OUT about a quarter turn. trim timing, trim idle speed. The key here, is that if your speed screw is too far IN, you'll bypass the mix screw and it won't affect any changes no matter where you set it. and you can set it too lean to run well enough to pass smog, so be careful there too...you'll also want to make sure your air injection is working.
mix screw turns IN to LEAN/// OUT to RICH. turn it in gently till it just touches bottom- do not torque it into its seat.I like to back mine out about 4 full turns, back off the idle speed screw till it's just touching the plate, then choke it and start it and let it warm up. once warm, slowly open the choke- if your idle speed screw is too far out, you might need to close the choke real quick to keep the truck running, then add a little more idle speed screw just enough to keep it running slowly without the choke. (about 450-550 rpm) once it'll run without choke, set speed to about 625, then slowly turn mix screw IN till the idle speed drops. (turn screw, wait for idle to respond, listen for change in speed; repeat) once you notice a drop in idle, turn the mix screw OUT about a quarter turn. trim timing, trim idle speed. The key here, is that if your speed screw is too far IN, you'll bypass the mix screw and it won't affect any changes no matter where you set it. and you can set it too lean to run well enough to pass smog, so be careful there too...you'll also want to make sure your air injection is working.
maybe, or damaged seat or too much throttle speed screw...if the plate is open far enough, the idle circuit is bypassed and that mix screw won't be in the "mix"...if you unplug the idle solenoid while the mix screw is closed and it keeps running, you're running too much speed screw...if you're running too much speed screw, screw it in slowly till the truck just dies flat out, turn your mix screw back out 4 turns and start from there. if it still won't stay running without the choke, or turning the speed screw back in, you have a vacuum leak. find it, fix it and start again.
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