Recondition a weber 32dfm twin choke downdraught carburetor

Once the air filter housing is removed, the various components of the carburetor can be cleaned and/or replaced. The fuel inlet was unscrewed ( [link] ) to allow for air to be blown through. Turning the carburetor upside-down allows access to the strainer (fuel filter) inspection plug ( [link] ), which is unscrewed to reveal the strainer assembly ( [link] ). The strainer assembly (filter) is carefully removed by hand or using tweezers and replaced with a new assembly that is included in the rebuild kit ( [link] ). The fuel channels are blown out with air prior to inserting the new strainer assembly and refitting the inspection plug.

The top of the carburetor is removed by removing six ( [link] ) cover fixing screws with a flat head screwdriver ( [link] ). This allows access to the float assembly and jets. Taking the cover of the carburetor first, the cover gasket is removed. The cover is then turned upside down so the float assembly is on top ( [link] ). The float fixing pin that holds the float assembly in place is removed by pushing from one side ( [link] A). Once the float assembly is free, the needle of the needle valve can be unhooked ( [link] and [link] ). Using a 10 mm wrench or socket undo the needle valve seating and remove the gasket below. Replacement seating and gasket are provided in the rebuild kit ( [link] ). The new gasket is fitted along with the new needle valve seating. The hook on the new needle valve is hooked onto the float, and the float assembly positioned into the carburetor cover. The fulcrum pin is inserted into the two posts to hold the float assembly in place. It is always worth checking that the height of the floats has not changed during this procedure.

Before the carburetor cover is reattached to the body, each the main and air corrector jets ( [link] ) were removed and cleaned with break fluid and compressed air. In addition, the accelerator pump ( [link] A) is removed by unscrewing the pump delivery valve ( [link] D). The old gaskets are replaced by new ones from the rebuild kit ( [link] B and C). The accelerator pump is reattached and screwed in place.

The accelerator pump cover is removed by undoing the four screws that hold it in place ( [link] ). With the cover of the accelerator pump diaphragm assembly will fall out along with the pump loading spring ( [link] ). The spring is refitted into the cup in the body of the carburetor ( [link] ). The new accelerator pump diaphragm assembly ( [link] B) is held in the cover assembly and the whole unit reattached, and screwed in place ( [link] ).

The idling jet holder on the same side of the carburetor body as the accelerator pump ( [link] ) is unscrewed and the primary idle jet removed and cleaned ( [link] ) before replacing back into the carburetor body with a new washer. This process is repeated for the secondary idling jet on the other side of the carburetor.

The cover gasket is replaced on the cover of the carburetor ensuring that the floats are not hindered from movement. The cover is then carefully replaced and the cover fixing screws. The air filter housing is replaced along with the fuel inlet. The filter will be replaced with a new unit once the clearance with the bonnet is checked upon instillation.

Resources

• Southern Carburetters, Unit 7 Priestley Way, Crawley, West Sussex. RH10 9NT, UK. Tel: +44 (0) 1293 533843. www.sciperformance.co.uk .
• Pegasus Auto Racing Supplies, 2475 S 179th Street, New Berlin WI 53146, USA. Tel: +1 262 317 1234. www.pegasusautoracing.com .
• Weber Carbs Direct, 20 Constance Court, Hauppauge, NY 11788, USA. Tel: +1 866 679 3237. www.webercarbsdirect.com .

Bibliography

• A. K. Legg, D. Peers, R. Maddox, and J. Haynes, The Haynes Weber Carburetor Manual , Haynes Publishing Group, Sparkford, UK (1995).