SU Carburetor Rebuild Service

Work begins with a thorough examination of the carburetters which are photographed to record the linkage arrangement and general setup prior to being dismantled.

When dismantling particular attention is paid to cast components for any damage. If any damage is found that would affect work being carried out you will be contacted to discuss options and pricing for any additional parts required.

Once the carburetters are stripped the next stage is to clean the component parts. All jobsare carried out on a one to one basis ensuring continuity throughout and where there is a sufficient build up of greasy deposits, the carburetters are initially cleaned using a combination of hot wash or agitated degreasing process prior to any blasting work.

The next process is to blast components with a blasting machine. The type of blasting we carry out must not be confused with the more industrial sand blasting techniques in common practice elsewhere.For sensitive parts like zinc and aluminium based bodies of carburetters, which often have high tolerances in their machining, a very gentle media is used so as not to harm the surfaces or push machining out of tolerance.

The final part of the cleaning process is the finishing stage, which is carried out using a specialist vibration machine with ceramic media and soap. A combination of extensive trials and years of experience has enabled us to replicate the original appearance of components.

Plating, polishing and painting is undertaken by trusted external partners who have worked with us for many years. to ensure we take due care of your valuable parts we personally hand-deliver and collect as required.

Once all the finishing is completed the rebuilding process can begin. Checks are made against original specification sheets to ensure the rebuild is exactly as original. If the setup is bespoke we will rebuild the carburetters to the same setup that they arrived with us. this ensures that the carburetters will be suitable to refit to an engine in standard form or one that has been previously modified in some way.

The most important step within the restoration process to ensure that the carburetters function correctly is rebushing the bodies. Accuracy is essential in order to keep the spindle perfectly central to the throttle bore otherwise the disc is unlikely to close correctly resulting in a poor idle. We do this using specialist drill bits on a lathe to avoid drilling all the way through the inner bore.

In Conjuction with this on many older models of carburetter we will cut a bespoke throttle disc. This is due to ovality within the bore that develops after many years of use. Fitting a specially cut disc will ensure good idle speed performance within the carburetter.

As part of our rebuild the wearing carburetor parts are replaced as a matter of course. Specification specific items such as levers, stops & linkages will be cleaned and re-used unless the condition of the part does not meet our high standards.

Once your carburetters have been rebuilt they are tested to ensure they operate correctly and set to a factory standard setup ready for you to fine tune on your engine.

Carburetters are initally tested using an exhauster. This machine simulates the vacuum of an engine so that the carburetter piston can be checked to ensure correct lift within standard parameters and that the disc closes down sufficiently to stall the engine. The idle speed is then set and if there is more than one carburetter, they are balanced.

After this process we perform a wet test. The carburetter is filled with fluid to ensure there are no leaks around the seals and the fuel level in the float chamber is set correctly. This test also checks that the float needle valve shuts off correctly and holds pressure.

If your carburetters were supplied to us with a manifold we will assemble the carburetters and linkages to the manifold to ensure smooth operation of the throttles and choke prior to contacting you to arrange payment and shipping.