72 Chevy k20 350 won't start

[chevytruckluver]

Originally Posted by 72chevydump

Ok here's the Situation I'm in.

After the truck is warm it's idling high. If I turn the dizzy to get it to idle better when I work the throttle it pops back through the carb. So with the idle sounding pretty good I tried adjusting the front 2 screws. What are those 2 screws? Because it seems no matter where I turn them it doesn't change anything? I think im close I havin it running good it just needs some fine tuning.
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Step 1 get a timing light and set the timing, then tighten the dizzy.
Do not use timing to adjust idle speed
Step 2 make sure you have no vacumm leaks or misfires (any problems need to be fixed before you can proceed further) then adjust idle speed
After you have the idle speed set on a warm engine then you can adjust the 2 screws for the idle mixture. These screws will not have an effect on anything at speeds above idle.
Step 3 recheck timing
Step 4 let us know how it's going after that
Good luck
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[72chevydump]

I hooked up a timing light and it was at 15 deg so I turned the dizzy until it was at 10 deg. Then I adjusted the idle screw down to were it sounded pretty good( didnt have a tach at the time). I then rechecked the timing and it was off again so I brought it back to 10deg. I took it for a test drive and it was 10x better than yesterday. Dunno when I will get to jump back on it but I will grab my multimeter that has a tach in it and get the idle set better. Then start adjusting the mixture screws.

What are the idle rpm's supposed to be set at?
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[72chevydump]

Alright so I got it in time at 8*btdc then tightened dizzy. Then i adjusted my idle screw n brought the idle down to around 750rpms. Rechecked timing and now it was at like 14-16* btdc. All of this is done with vac advance unplugged at dizzy and plugged with a screw. Am I doing something wrong or what. Everytime I make one adj and then go to do the next it always throws something off
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[72chevydump]

I just changed the plugs again to AC delcos. Still has a slight popping out the exhaust at idle and some hesitation and bog when you first get on the throttle? Could it still be timing issues?
Also the valves need adjusted but when u rev it to say 3000rpm it has a sound like a clang or tang coming from the #5 cyl area in the valve cover?
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