Why Is My Holley Carburetor Flooding?
An indication of flooding can be gas flowing out the top of the carburetor, gas seeping out of the throttle shaft, or a very strong odor of gas. There can be one of several things that will cause your Holley to flood. Here is a list, not necessarily in any order.
- The most common cause for Holley flooding is the needle & seat. This is where gas comes into the carburetor to fill the bowl. Anything wrong with the needle can cause excess gas to enter. For a quick possible fix, blow some air into the inlet in hopes that is dislodges any foreign matter. Turn the carburetor upside down and blow into the inlet. Air should not be able to bypass the needle. Don't blow more than 4-4.5 lbs.
When adjusting the float on the Holley 2209, 2210 or 2245 be sure you don't put any pressure on the needle, or it will get damaged. - Check the float for leaks. A brass float can be immersed into hot water to see if any bubbles form. For Nitrophyl float, replace it. They can only be weighed to see if they have absorbed fuel.
- Move the float up and down by hand to see if it catches anywhere. The float pin could be worn.
- Check the fuel pump pressure. Should be around 4-4.5 lbs. New pumps are especially suspect. If you do have a new pump then consider adding a regulator between the fuel pump and carburetor.
My Car Won't Start After It Gets Hot
- After running the vehicle and it is hot, turn it off and look down the carburetor to see if there is gas dripping from the venturi. That is excess gas that will build up on the intake causing it to be too rich to start. If gas is leaking, then you may have a check ball leaking, or maybe a bowl vent blocked. Check any rubber hose coming from the carburetor for kinks.
Heat Soak: If your car starts fine when it's cold but has trouble when it's hot, you might be experiencing heat soak. This can occur when the heat from the engine warms the fuel in the carburetor, causing it to vaporize or "percolate" before it can get to the combustion chamber.
- Carburetor Tuning: If your carburetor is improperly tuned, it might be delivering too much or too little fuel when the engine is hot, causing hard starting.
- Choke Setting: If the choke is not properly adjusted, it may be causing the engine to flood when it's hot, which can make it difficult to start.
- Fuel Pressure: If the fuel pressure is too high, it can force too much fuel into the carburetor, causing a rich condition that makes it hard to start when hot.
- Ignition Timing: If the ignition timing is too advanced, it can make it harder for the engine to turn over when hot, resulting in difficult starting.
- Mechanical Problems: Issues like low compression, worn ignition components, or a failing fuel pump can also cause hard starting when hot.
Why is There No Vacuum At The Distributor Advance?
On many carburetors this is normal. It could be a ported type of carburetor.My Carburetor is Running Rich
Black smoke coming out of the tailpipe, or strong gas smell from the engine may indicate a rich condition.
- The 1st thing people want to do is adjust the size of the main jet. That might be the answer if the carburetor came from an unknown source but for a carburetor that you have been running, the jet size doesn't suddenly change.
- Now if the carburetor is a transplant then there is a good possibility it is jetted wrong. For a rich condition, reduce the jet size by .002 and try again. Check your plugs to see how they are burning.
- Reasons that can cause flooding can also cause a rich condition. See the list above.
