How to Diagnose and Troubleshoot Common Chevrolet Carburetor Issues
Whether your engine is hot or cold, when the carburetor is working properly and immaculately clean, your motor should always start easily, accelerate without any stumbles, and idle as smoothly as butter. Your engine should enjoy emissions that are within the limits for the year your vehicle is made and get normal to superb fuel economy to boot. When you have a questionable, bad, or dirty carburetor, then certain problems and symptoms of damage will crop up, such as poor fuel economy, idling too fast, flooding, rough idle, stalling, hesitation, and hard starting. Carburetors are expensive to replace and tricky to rebuild, so make sure your diagnosis of carburetor problems is correct before you even touch this component.
Problems when starting an engine
Carburetor issues are myriad. There are even times when it 's something else other than the carburetor causing these issues. However, more often than not, a quick tune-up or overhaul of your carburetor might be handy during such instances depending on the severity of the damage. If your heat riser is plugged with rust or your heating coil is not receiving voltage or is burned out, your choke won 't heat up properly, making your engine idle too fast and run rich because the choke is activated all the time or for far too long. Thusly, replace or repair the components in question. Meanwhile, if the shaft that opens and closes the choke is filthy, it should be cleaned out since it will make the choke stick.
Hesitation or stumble when accelerating
A maladjusted or dirty carburetor as well as worn throttle shafts or a weak accelerator pump could be the cause of hesitation when you 're accelerating. It 's the lean fuel mixture of not enough fuel and too much air caused by a compromised carburetor or some other component that makes your Chevy hesitate. Therefore, you should replace or rebuild the carburetor as required. You want your accelerator pump to squirt an extra dose of fuel to the carburetor 's throat whenever the throttle opens. Once this process is somehow mitigated, your carburetor will fail to offset the extra gulp of air that 's sucked in until fuel flow through metering circuits can catch up to air velocity changes.
If the idle speed is too low, your engine can end up stalling. This can also happen when your ignition system runs out of spark, your fuel stops flowing or won 't burn, or your fuel mix is too lean. A carburetor might require rebuilding or replacement if a sticky needle valve is starving the carburetor for fuel or there are air leaks within the car part itself. You can also clean up the carburetor thoroughly if it 's so plugged or dirty that the metering passageways, air bleeds, or jets are blocked. An outright overhaul might be needed if the carburetor housing is severely damaged or warped or if the throttle shafts are too badly worn.
A rough idle happens whenever you get a lean misfire due to an overly lean fuel mixture. You usually get idle problems because of air leaks between the intake manifold and carburetor. To fix this, replace the gasket under the carburetor or tighten the carburetor base bolts. A rough idle is also an indicator of air leaks on the PCV system, EGR valve, or vacuum lines. Have these components looked at and let your mechanic decide whether they require repair or replacement. If your idle mixture circuit is also leaking, then you might require cleaning and rebuilding of your carburetor.