VW Fuel Injection to Carburetor Conversion Kit

Fuel Injection to Carburetor Conversion

Installing the carburetor conversion kit is an involved process but we have put together a brief list of the steps and instructions to converting your Beetle from fuel injection to carburetor.

The installation begins with disconnecting the battery as various engine wires will be disconnected. From there all of the factory fuel injection components need to be removed. This includes the air box and breather hoses, air flow meter, throttle body, intake manifold, end castings (with fuel injectors), etc. The fuel hoses and wiring in the engine compartment connecting to the fuel injection components need to be disconnected and removed as well. The alternator needs to be unstrapped from the stand and the fuel injected intake manifold and alternator stand can be removed.

With the majority of the upper engine components removed you can pull the accelerator cable from the fan shroud, and remove the fan shroud to drill the new guide hole for the accelerator cable. Or you can install a new (or used) doghouse fan shroud that is already drilled for the carburetor cable.

Install the oil deflect plate and new alternator stand. With the new stand in place, strap the alternator down to the stand. The new oil filler tube can be screwed into the new stand as well. The drilled, new or used fan shroud and alternator can now be set in placed (while guiding the accelerator cable through) and the alternator can be strapped in place.

The new intake manifold now slides in place and the boots and clamps slide in place on either side. Install one of the intake end castings (after installing new gaskets at both heads) and slide the manifold and boot in place. Repeat the process for the opposite side intake end casting. Note that the intake manifold has heat risers (not installed) but unless you change your factory exhaust, they will not be hooked up. In warmer climates this isn't a major issue. In colder climates we highly recommend swapping the complete exhaust to a carbureted style (which is a good idea regardless of climate). If you have already swapped to a carbureted style muffler or exhaust install the heat risers in to the manifold and bolt them to the heat risers on the exhaust after installing new gaskets at the exhaust. With everything installed on the intake manifold in place tighten all of the nuts, bolts and manifold boot clamps.

Now install the new carburetor base gasket followed by the carburetor and tighten the mounting nuts. Install the fuel line at the carburetor and clamp it in place. Route the opposite end of the the left side of the engine and connect the hose to the original fuel hose or line. Then install the air filter and breather hose, the breather hose will route from the vent port on the bottom of the air cleaner to the vent port on the oil filler. Attach the re-routed accelerator cable to the carburetor linkage. Run a power wire from the positive side of the coil, to the idle solenoid on the carburetor, then to the choke element. This coil circuit is not fused so make sure the wire is routed away from any possible shorts.

The majority of the conversion is complete with the exception of the fuel system. The fuel injection system uses a relay that is controlled by the fuel injection computer to send power to the fuel pump. The relay, computer and pump need to be removed. The fuel return lines from the engine at the fuel pressure regulator back to the tank can be removed or capped off. Most importantly, cap off or plug the return line at the fuel tank.

The original fuel line from the tank to the pump can be re-used and installed at the inlet of the new fuel filter. Use a small section of hose to connect the filter to the inlet of the new electric fuel pump, then connect the original line to the new fuel pump outlet. Make sure the fuel pump is mounted securely to the chassis. The black wire is the ground wire for the pump and it can be grounded at the chassis mount. Power to the fuel pump can be sourced from any "key" hot fuse on the fuse box. The pump typically uses less than 5 amps of power.

At this point the installation is now complete, hook up the battery, turn on the key to ensure the fuel pump is working. Then check for and repair and fuel leaks. Start the car and double check the ignition timing and adjust (or have a mechanic adjust) the carburetor as needed.