My 2 barrel backfires on cold days andif I take off before I let the car warm up. Lets say its the carb what can I do? How much damage if being done when it backfires. Is there a way to get a carb built for cold weather? I have a friend who says he never had a problem with cold weather in his lark
:idea2: Ok now if the choke is not set right it won't start correctly and can cause a backfire . With the engine cold , pull the throttle back till the choke plate closes . Then see if the gap is oh lets say about a 1/8 in or so . Also if the choke opens too quick due to a bad choke pull off if equiped it can also cause problems . But lets Start with the choke setting before we make this a huge project .. Let's here what it looks like .. If is too big it won't start right . Oh , Is the carb / choke clean ?
The carburetor is jetted for emissions and is meant to run with the stock air cleaner. The stock air cleaner uses heated air drawn from around the exhaust manifold stove. The air cleaner sensor and door in the snorkel are meant to keep the air at about 115*. The carburetor is calibrated to work with this heated air. If the stock air cleaner is not connected correctly or is not functioning correctly, the engine will be lean especially when cold. It will backfire through the carburetor when it is too lean. It won't cause any damage, but the engine will hesitate. I would check to make sure your choke is operating correctly as was recommended. Also make sure your vacuum advance is hooked directly to the carburetor and that it is working.
Do what what was mentioned above but maybe try this first. I also had a problem with my 2bbl where the bolts on. The carb loosened (or the gasket settled) and I had a big vacuum leak. I was able to turn the bolts with my fingers.
Most of the time a cold engine back fire is caused by a lean condition,,, now what causes that lean condition,,,,here in Tn. I dont even use a choke, I take it completely off the carb to pick up some more cfms... i start the engine on the accellerator pump.... a few pats to richen up the mixture , let it set a minute to vaporize some and fire up... then lightly tap the accelerator once in a while to keep the engine running till it warms up enough to smooth out...In the 70s the factory jetted the cars right on the ragged edge of too lean to meet emissions standards,,, When they came out with pcv valves , mechanics cussed them, when the egr valves came on, the mechanics really cussed them,,, as a car ages , things get out of spec,,, and then the engine can run lean,, start out and systematicly ck out each thing that affects driveability and you will most likely find a combo of reasons... but first get the electrical right, including the vacume advance and then look at the carb.... but dont overlook cat pee gas....
Found the problem thanks larry for the info:Smarty: , thanks James... the guy I bought the heat stove from:beers2: The cold air was the cause of the back firing when i started to drive. The heat stove and aluminum pipe that connects to the air cleaner housing are I was missing, but were very important parts for cold weather driving. Thanks, everyone :TU:
Not only does it drive better in cold weather. It heats up faster and performs better in freezing weather. The temp is 15 degrees more than it used to be @ normal running temps
