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How To Check A Ford VV Carburettor?

It’s fairly easy to check a Ford VV carburettor. The Ford VV carburettor (Ford Variable Venturi carburettor) is fitted in many smaller Ford models. It resembles a lot to a fixed-jet carburettor. A carburettor requires checking and cleaning once every year.

It’s important to know how to check a Ford VV carburettor because if it’s not been cleaned or checked for a long time, it may not work properly. We’ll let you know several simple steps to properly check and clean your Ford carburettor.

What’s A Carburettor?

Before you know how to check your Ford carburettor, knowing exactly what the use of a carburettor is important. Knowing what it’s used for and having brief info regarding how it works is helpful.

The main purpose of a car carburettor is to make the perfect fuel-air mixture for the car’s engine. Gasoline engines are manufactured in a way that they take in an accurate amount of air so the fuel can burn properly. Either it is getting hot by running at top speed or starting from cold. Your car’s carburettor helps greatly by making the optimum fuel-air mixture for your engine.  

A carburettor has tubes that send fuel and air into the engine through valves and combines them together in varying quantities to suit different driving conditions. A carburettor that is in good condition can help you drive faster and easier.

Why Is It Important To Check A Carburettor?

A car carburettor will not work properly if it hasn’t been cleaned or checked for a considerably long period of time. Having a clean carburettor helps your car’s engine to run efficiently, prevent from rust to occur and saves you from hefty replacement costs.

 Rust not only can damage your car’s exterior, but it can be very bad for your car components as well, like the carburettor. It’s best to check for rust on the outside and the inside of your car every now and then.

Checking A Ford VV Carburettor

The Ford Variable Venturi carburettor, similar to a standard fixed-jet carburettor, has similar features as well, like an accelerator pump. Its main functioning is of the constant-depression type, similar to an SU, but it is tilted to 90 degrees. Like other car components, the carburettor can collect sediments and dirt over time, so you’ll have to check and clean it.

If your car is not starting, then a dirty or worn-out carburettor may be the cause, so it’s best to clean it as soon as possible. 

There are several fragile tiny parts, so be careful when cleaning your Ford VV carburettor. Purchase replacements for the gaskets and replacements for the needle, jet and float needle valve if any of these are worn out.

Take out the carburettor to clean it. Removing the carburettor doesn’t take much effort, so you don’t have to worry. It’s fairly similar to removing a car radiator. Keep the carburettor upright to avoid fuel spills.

Before dismantling, clean the surface to prevent dirt from piling up within. Clean these parts by rinsing them in petrol and then use a rag that is free of lint to dry them. Avoid rinsing the diaphragms and put them in a dry clean area.

Choke Adjustment

 After you’re done with reassembling, proceed to lightly oil the external moving parts. Remember how many times you turned to unscrew the adjustable parts, such as the needle, to refit them in the same place. Remember parts like washers and when and where you refitted them to avoid fitting any part in the incorrect sequence.

The Ford VV carburettor choke is automatic and adjustable. The rich setting is for unusual weather, and lean is for decent weather. You don’t have to adjust it on your own as Ford pre-sets them.

Remove The Jet Body And Needle

Remove the screws that hold the jet body, and there will be four screws. Then remove the block that holds the main jet. After that, lift the jet body out. Check if the jet has worn out as it commonly does.

Taking The Needle Out

Remove the screws from the top of the body and then take out the top lid. The lid is plain and has no added attachments to it. Push the plastic blanking disc from the inside. This disc is located at the opposite of the needle end.

Refit the disc after you’re done with reassembling. Take out the screws of the needle of the blanking-disc hole, and just like before, count how many times you have to turn to unscrew the needle. Pull out the needle without bending it. Proceed to check the needle, and if it is worn out, you’ll have to renew it.

Float And Needle Valve Checking

Loosen the float pivot from its clips. Shake the float pivot to ensure there are no fuel leaks. If your car is leaking fuel, then renew the float as it might be one of the causes. While you’re checking fuel-related issues, take a look at other fuel components to make sure the float isn’t the cause of the leak. Check the fuel sender unit or any other part to confirm such suspicions.

Pull out the float needle from the valve and see if either the seating or needle has been worn out. A needle valve that has been worn out can be a cause of flooding and will need replacing. Clean the float chamber with some petrol and use a lint-free rag as previously to dry it out.

Checking The Diaphragm

Take out the screws that hold the diaphragm covering. Take out screws from the duvet and spring that are under it. Slowly take out the diaphragm’s sides from the carburettor body. Push off the circlip that holds the diaphragm. This will free it. Avoid nicking the diaphragm when you’re freeing and checking it.

Similarly, with the accelerator pump, check and refit the diaphragm the same way. A spring is located in the piston that is a part of the air valve. This is inside the square aperture at the top and to the left of the diaphragm. This position confirms that it is centrally placed and points upwards before you refit it.

When you’re cleaning pistons, you don’t necessarily have to remove them, as there are some ways to clean pistons without removing them. Some of these ways include using fuel enhancer or engine oil.

Taking Out The Accelerator Pump

There are three screws that you’ll need to unscrew to take the duvet of the acceleration pump out. Take out the diaphragm while keeping in mind where the exterior is and which way is the interior.

See if there are any cracks, holes or wrinkles on the diaphragm. Even a pin hole can cause damage to the functioning of the diaphragm, so you should check very carefully. If there is noticeable damage on the surface of the diaphragm, then replace it with a new diaphragm. Ensure the jets below the diaphragm are clean as well.

To clean the jets, you’ve to remove them and wash them in petrol and blow them with a foot pump. Avoid using wires or brushes on jets as it’ll damage them. Even if your brush is super soft, it will damage the jet and block it.

Our List Of Highly Rated Carburettors

Following is the list of the best carburettors for replacing your old Ford VV carburettor.

1.     New Holley Street Demon Carburettor

This carburettor guarantees to provide optimum performance with easy functionality and clean looks. It has the square bore flange bolt pattern, and it can easily replace a number of carburettors, including Carter AFB, Edelbrock and Ford.


  • Shiny aluminum surface and finishing.
  • Used for stock or slightly modified V8 engines.
  • A design that perfectly fits with modern as well as traditional vehicles.
  • Easily cleanable single piece airhorn.
  • Single fuel inlet, so it easily be installed.


  • Patented timeless design.
  • Easily maintainable airhorn.
  • Integrated fuel bowl.
  • Dual mounting bolt pattern.


  • A rare occurrence of a fuel leak sometimes.

2.     Edelbrock 1406 Performer

A good high-quality carburettor replacement for your Ford VV carburettor with high prevention of oil leaks.


  • Includes a double piece, aluminum made construction for less warping and cooler operating temperatures.
  • Designed for good street performance.
  • Uses easily altered metering rods for accurate tuning.
  • Its choke has timed and full vacuum ports for ignition advance.


  • Designed for optimum performance.
  • Shiny silver finish.
  • Included with Edelbrock’s exclusive 90 day warrantee.
  • Single feed fuel inlet is present.


  • May not fit in some vehicles.

3.     Holley Vacuum Secondary Electric Choke Carburetor

Best for several different configurations such as for strip, street or track performance. The secondary vacuum helps in heavy vehicles, and it has an electrical choke.


  • Inclusion of an electrical choke.
  • Available in several configurations.
  • Shiny finish.
  • High performance.
  • 2 full manifolds included.
  • 1 timed vacuum port included.
  • Can fit in several models.


  • Shiny finishing.
  • Can provide consistent high volume fuel delivery.


  • No notable cons.