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W403 · 01-04-2008, 09:01 AM

I've struggled a little with the Quadrajet and even said a few foul words when running late and it didn't want to start/run. I've had mine for around 25 years now and since learned the beast. Obtaining a factory service manual from year one was the best medicine along with an HP book on understanding the unit itself. I believe there are about 25 adjustments outlined in the service manual, of which a few are variably adjustable. If you have all the settings correct, further tweaking hasn't corrected and it doesn't want to start, you most likely only need to enrich the choke by turning the housing cover counterclockwise one notch at a time until it starts and runs on it's own. I've have come thru this by learning the hard way and taking 3-4 times longer than trained tech would have in my early years. The biggest thing to mention here is the leaky main well plugs in the carb. Remove and disassemble the carb so you can access the underside of the main body. There will be 2 plugs underneath that leak and cause the main well/fuel bowl to drain down the intake and go empty. Take a file and flatten them down to fresh material, then apply an epoxy ( not the quick setting) enough to completely cover them. Be prepared to let them set overnight/24hrs depending on temperature and check them in the morning. This procedure is explained in several manuals published for the Quadrajet and is a real cure. ( Buy the manuals, trust me on this) I started mine the other evening when outside was around 32 deg., 2 pumps and vvrrrrooommmm. The RPM's slowly started to build as it got warmer. Also make sure your EFE system is operational as it enhances cold drivability along with the carb choke system adjustments. By the way mine can actually be driven after only a few minutes of warm up in cold weather when everything is set/adjusted correctly and it doesn't want to 'run away' either. I also had installed an HEI early on which requires replacing the resistor feed wire with standard style in order to obtain a 12v source from the ignition switch. Good luck, hope this helps.

01-04-2008, 09:01 AM	#7 (permalink)
W403 W403 Join Date: Jan 2008 Posts: 4	Cold carb remedies I've struggled a little with the Quadrajet and even said a few foul words when running late and it didn't want to start/run. I've had mine for around 25 years now and since learned the beast. Obtaining a factory service manual from year one was the best medicine along with an HP book on understanding the unit itself. I believe there are about 25 adjustments outlined in the service manual, of which a few are variably adjustable. If you have all the settings correct, further tweaking hasn't corrected and it doesn't want to start, you most likely only need to enrich the choke by turning the housing cover counterclockwise one notch at a time until it starts and runs on it's own. I've have come thru this by learning the hard way and taking 3-4 times longer than trained tech would have in my early years. The biggest thing to mention here is the leaky main well plugs in the carb. Remove and disassemble the carb so you can access the underside of the main body. There will be 2 plugs underneath that leak and cause the main well/fuel bowl to drain down the intake and go empty. Take a file and flatten them down to fresh material, then apply an epoxy ( not the quick setting) enough to completely cover them. Be prepared to let them set overnight/24hrs depending on temperature and check them in the morning. This procedure is explained in several manuals published for the Quadrajet and is a real cure. ( Buy the manuals, trust me on this) I started mine the other evening when outside was around 32 deg., 2 pumps and vvrrrrooommmm. The RPM's slowly started to build as it got warmer. Also make sure your EFE system is operational as it enhances cold drivability along with the carb choke system adjustments. By the way mine can actually be driven after only a few minutes of warm up in cold weather when everything is set/adjusted correctly and it doesn't want to 'run away' either. I also had installed an HEI early on which requires replacing the resistor feed wire with standard style in order to obtain a 12v source from the ignition switch. Good luck, hope this helps.