Please help with tuning engine dies when cold.
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Junior User
Joined: Apr 2004
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From: oregon
Please help with tuning engine dies when cold.
Ok so I just installed headers, offy c series and rebuilt 600 cfm holley carb. I have fresh ngk plugs and I read them and I appear to be in the correct mixture. The problem is that when the engine is cold it doesn't want to start without a lot of pumping and dies when placed into gear It runs fine when it has warmed up for a few minutes. Also the holley has an auto choke, I haven't set this will it help, how do I set it? I have set the timing by ear for now. I also have my distributor vacuum advance hooked up to the port above the mixture screw and not the manifold vacuum as per suggestion by the frenchflyer and it seams to not die as much when doing this. Cap and rotor are new and wires are in excellent shape. Any ideas? Also its hooked to a C4 2wd.
Thanks
Thanks
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Junior User
Joined: Apr 2004
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From: oregon
Ok do to some tips from fordsix.com I adjusted the choke with the engine cold. It started up fine. Then I discovered that the thermostat has been removed. Any recommrndations for a thermostat? I am afraid if I don't install a thermostat the engine won't get hot enough to move the choke to open.
Elder User
Joined: Apr 2001
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From: Glen Burnie Maryland
for a 77 I'd go with a 180-185 thermostat.
If your choke housing has a electrical connection (and a lot do now) then hook up a switched 12VDC line to it. Switched meaning it's only on when the ignition switch is in the on position. This will take care of your choke heat.
If not and the carb has a "Choke Heat Tube" there should be a small hole in the exhaust manifold that the tube slips into. Vacuum from the carb will pull heated air from the exhaust manifold thru the tube and warm the choke coil and open the choke plate.
"EDIT" D'OH!!!! Just re-read the original post. You have headers. In which case I'd take the same diameter tube only longer and wrap one of the header tubes 2-3 times with the tube and then clamp it down. Now your getting inductive heating of the tube and also the air. This will work. Put it up close to the intake so it will be either hidden (for good looks) or partially hidden (so you can get to it as needed.).
Clear as mud????
Larry
If your choke housing has a electrical connection (and a lot do now) then hook up a switched 12VDC line to it. Switched meaning it's only on when the ignition switch is in the on position. This will take care of your choke heat.
If not and the carb has a "Choke Heat Tube" there should be a small hole in the exhaust manifold that the tube slips into. Vacuum from the carb will pull heated air from the exhaust manifold thru the tube and warm the choke coil and open the choke plate.
"EDIT" D'OH!!!! Just re-read the original post. You have headers. In which case I'd take the same diameter tube only longer and wrap one of the header tubes 2-3 times with the tube and then clamp it down. Now your getting inductive heating of the tube and also the air. This will work. Put it up close to the intake so it will be either hidden (for good looks) or partially hidden (so you can get to it as needed.).
Clear as mud????
Larry
Last edited by larry derouin; May 30, 2004 at 05:32 AM.
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Junior User
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From: oregon
Ok I think we are getting there, although it does have a black tube that it pulls air through the choke heat sensitive coil, this tube is already rounted to the top of the carb, heres a pic http://i11.ebayimg.com/02/i/01/c6/07/c9_1.JPG
in the pic you can see the black cover for the auto choke that has to be rotated for adjustment, you can also see the black tube that I mentioned. Also its an auto choke so no electrical hookup.
in the pic you can see the black cover for the auto choke that has to be rotated for adjustment, you can also see the black tube that I mentioned. Also its an auto choke so no electrical hookup.
Elder User
Joined: Apr 2001
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From: Glen Burnie Maryland
Ok you DO NOT have Electric Assist. The Rubber tube that comes off the secondaries side is probably not for the choke, as it would only supply cold air. I think it may have to do more with the vacuum pull off for the secondaries.
With the choke off the car loosen the 2-3 screws that hold the cap down. Rotate, I think counterclockwise, until the choke plate just touches the back of the primary throat. Tighten the screws just enough to hold tension.
Now with the choke closed, open the throttle ALL THE WAY or Wide OPEN THROTTLE (WOT). The choke flap should back off until there is about 1/8" to 3/16" of opening. No more than 3/16". Adjust choke cap until you get this measurement. Now put it on the car, prime with gas (coil wire off, crank for 20 sec. or so, or until pumping the throttle shoots gas down the throat). Hook up coil and start. Adjust fast idle, and when warm, Idle mixture, idle speed, and float level. You might also need to get a re-jet kit and lean it down or Richen it up, depending on your plug readings.
Larry
With the choke off the car loosen the 2-3 screws that hold the cap down. Rotate, I think counterclockwise, until the choke plate just touches the back of the primary throat. Tighten the screws just enough to hold tension.
Now with the choke closed, open the throttle ALL THE WAY or Wide OPEN THROTTLE (WOT). The choke flap should back off until there is about 1/8" to 3/16" of opening. No more than 3/16". Adjust choke cap until you get this measurement. Now put it on the car, prime with gas (coil wire off, crank for 20 sec. or so, or until pumping the throttle shoots gas down the throat). Hook up coil and start. Adjust fast idle, and when warm, Idle mixture, idle speed, and float level. You might also need to get a re-jet kit and lean it down or Richen it up, depending on your plug readings.
Larry
