Note: Picture to be used for reference only. Carburetor models may vary.
Note: Please read the WARNINGS below.
NOTE: Our full gasket kit will help seal the carburetor in the event of leaks (and clean, new gaskets are always recommended when any carburetor is taken apart), but it always pays to check and repair all the gasket surfaces for cuts, nicks or grooves that can cause poor sealing. It is also a good opportunity to remove any dirt and other foreign materials from the carburetor.
a) Disconnect the accelerator pump rod (3) from the ball sockets at each end. Disconnect the choke valve tension spring (14) using small pliers, and remove the choke lever fulcrum screw (1). Remove the five airhorn screws (31) and their lock washers. Lift the airhorn (32) off, with the accelerator pump (10) attached. Remove the airhorn gasket (20) at the same time.
b) Remove the small split (cotter) pin from the top of the accelerator pump, then use a small screwdriver or pliers to unhook the spring (33) from the accelerator pump fulcrum lever (34). Now remove the screw (35) to release the lever from the airhorn casting. Now you can remove the accelerator pump down through the casting. Replace the felt gasket at the top of the pump with the new one from the kit.
c) Remove the three bowl casting screws (not shown) and their lock washers and lift the bowl casting (24) from the throttle body (base) (9). Lift off the gasket (25), replace the new one on top of the throttle body and fix the bowl casting back on, remembering the three lock washers. Tighten the screws gradually to 10 in/lb torque. Do not over- tighten
d) Remove the three bowl plugs (48 x 2 and 43) and their gaskets (44) from beneath the float bowl. Inspect the three plug gasket surfaces in the bowl casting. If you see anything that might prevent the gasket from sealing, you may need to spot face the gasket surface to get a good fuel-tight seal. A good machine shop can do this for you using a 0.6in OD cutter tool. With good gasket surfaces, fit a new ring gasket (44) to each bowl plug and install them back into the casting. Note: The kit includes two spare bowl plug gaskets for future use (eg. when changing jets). Take care to avoid cross-threading the plugs into the castings, especially the outer ones. And use the widest screwdriver blade you can, to avoid marking the slots in the plugs.
e) Remove the power valve (28) and its ring gasket (29) from the bottom of the accelerator pump well. We recommend a wide, flat blade screwdriver with a slot cut in the the blade to clear the delicate pin in the top of the power valve. Failure to use a correct tool may damage the power valve. Place the new gasket (29) on the power valve (it’s the smallest one in the kit) and fix the power valve back into the casting. Do not over-tighten.
f) Install the top of the accelerator pump (10), back into the airhorn casting from underneath, then install the spring (33), lever (34) and screw (35), reconnecting the pump to the lever as you go. The ball on the end of the lever points outwards as in the diagram. Do not hook the spring on the lever yet. Place the new airhorn gasket (20) – the right way around! – on the bowl casting and sit the airhorn back on, taking care not to wrinkle the leather seal or catch it on the slot in the pump well. Don’t allow the pump to rise upwards or it could catch again. Now fasten the airhorn down with the five lock washers and screws to 5in/lb torque. Attach the choke tension spring and connect the choke lever to the airhorn with the screw. Reconnect the accelerator pump rod (1) and flip the pump lever spring back onto the lever.
g) Finally, remove the inlet valve (14) – needle and seat or Stromberg S-jet – using an 11/16th open-end wrench and swap in the new ring gasket. If you are simply swapping gaskets, the float level adjustment should remain the same. The final gasket to be replaced – the manifold gasket (6) – goes between intake manifold and carburetor when you fix it back onto the engine.
You’re done! If you think we’ve missed anything or we could improve on this Genuine Stromberg ‘How To’, please let us know. Email – firstname.lastname@example.org