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Just bought 1960 F100 223, Holley 1904 1BBL. Timing OK.Dwell OK Opened carb and can blow compressed air through idle fuel passages. Have replaces plugs, points, condenser,& coil. Compressipon is (dry/wet)
130/140 125/140 110/11590/95 125/130 105/115
Truck will not idle below ~1000 rpm.
Is the above compression results bad enough to cause this poor idle?
Weird fact: With the choke in "Off" position the idle speed screw with the spring on will not touch the cam that it is supposed to ride on. I had to remove the spring so i couild open it up enough to make it "idle?"
Well congrats on the new truck and welcome to FTE!
Sounds like you are zeroing in on the idle trouble with the carb. They are fairly simple but they do have to be put together correctly. You may have some trouble in that dept. It's tough to tell just by typing and not seeing!?!
i am a little confused. you said with the choke "off" and then you went on to say you had to take the spring off so you could open it enough for it to idle? the blade on the top is the choke. there is a blade on the bottom that is for the throttle. i would make sure the upper is open and the lower is closed all the way. if the throttle is closed all the way you should only be pulling gas through the idle circuit. but what do i know
I tried to find vacuum leaks by spraying starting fluid on the lines but could not find any.
I said choke off, I meant open. The position of the choke controls the angle of the cam that the idle speed screw rides on to give a fast idle when the choke is closed or partially closed.
Is the throttle plate completely closed at idle? If so where does the air get in, through a passage in the carb?
Usually the throttle butterflys need to be open a little when curb idle is adjusted properly, sometimes not much at all. The idle circuit should also have an idle air passage since the idle mixture screw is just that, an adjustment of the fuel/air mixture on the idle circuit
Thanks Willowbilly. I think that is part of my trouble also, the tapered part of the idle misture screw is really mashed up. Must have been tuned by a gorilla. My supplier is having problems finding my kit, hopefully will get it soon.