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Old 10-04-2004, 02:23 AM   #1
Broken_down?
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Highway smoke?

Around town my truck does not smoke or anything, On the highway in the day it does not smoke either. But at night on the highway when I floor it to pass etc it lets out a smoke screen. How can I stop this from happening. It only happens at night when I floor it. I am thinking the only reason I see it at night is because of the head lights behind me. Anyone got any ideas?

Rich
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Old 10-04-2004, 06:42 AM   #2
rage'nrat638
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sounds like it's running a little rich......it's just unburned fuel......

drop in a 50,000 volt hei.......lean out the idel mixture screws......

have someone drive your truck.....kick it down.....drive there car behind your truck....watch.....ans sniff......you will see.....
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Old 10-04-2004, 10:37 AM   #3
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Sounds like a rich condition to me, too. R'n'R has the right idea, I think.

Dan
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Old 10-04-2004, 01:36 PM   #4
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wow thats a better answer ten I was expecting. Glad to hear it more then likely not the rings I only have the repair manul you get a autozone and it don't tell me the idle mix specs. Can someone suggest so pointers. I am doing all the work by myself and this is my 1st truck. So any help would be great!

:: EDIT::
Does the mixture have anything to do with the dwell spec? Does adjusting the timing effect the mixture? Cause IU was finally able to get the truck to stop pinging going up extremem hills. Hate to have the ping back.


Thanks

Rich
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Don't get upset when she marks her territory in the driveway.
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WHY DO THEY CALL THEM JUNKYARDS ANYWAY??? I LIKE TO THINK OF IT AS A TREASURE HUNTING MISSION

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Old 10-04-2004, 03:19 PM   #5
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Idle mixture screws affect fuel mixture, dwell is amount of time (in degrees)points are closed. To adjust idle screws, hook up a vaccuum gauge to the carb port that vaccuum hose to dist connects to. Slowly and gently turn the screws in (one at a time) until vaccuum is affected or until screw bottoms out. Then back the screw out until you reach max vaccuum on the gauge. (Repeat process for other screw) You may have to do a little fine tuning once you get both screws close to being right (repeat process without turning screws all the way in). Also you should maintain the same rpm while making adjustments to carb. As the idle speed increases as you adjust the screws, adjust your rpm at the same time to acheive consistant rpm. No, timing does not affect idle mixture. If you can't see the smoke in the daytime, (black or blue) I wouldn't worry about it. Good luck and keep on truckin'....................Jerry
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Old 10-04-2004, 03:37 PM   #6
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actually timing does affect fuel burn. if it is pinging you are not getting your spark at the right time to completly burn your gas. hence a rich mixture. ragenrat is right adjust carb +timing you should be good to go.
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