HS4 & HIF4 Piston & Suction Chamber Assembly | LZX 1968

Genuine SU HS4 piston and suction chamber assembly. The suction chamber and piston are the core of the SU carburettor's variable-choke mechanism. The piston rises and falls in response to engine demand, metering fuel via the attached needle. Replace if the piston is scratched, scored, or if there is excessive side play in the assembly.

Part Number: LZX 1968