Dashpot damper

MG: MGA 1600, 1622, De Luxe and Twin Cam (1958-62) • MGB with SU-HS4 and SU-HIF4 carburettors (1962-80)

Austin Healey: BN7 and BT7 with triple SU-HS4 carburettors

Sprite / Midget: All models fitted with SU carburettors (1958-79)

Triumph: Spitfire 1500 with SU-HS4 carburettor with AUD665 and FZX1258 reference no.'s (1974-80) • TR4A European models with SU-HS6 carburettors from chassis no. CTC62191

with vent and black hexagonal plastic head - length of the rod: 2.125"

Dashpot dampers are designed to slow the rise of the suction piston in the carburettor in order to give a richer mixture on snap acceleration. They vary considerably from type to type by varying the clearances in the assembled components. The oil in the dashpot is forced through the assembly and thus slows (dampens) the piston rise. A further difference is that some are externally vented (hole in the top) and some are internally vented (angled hole in the suction chamber) these are termed dustproof and non-dustproof respectively. It is essential that the correct part is fitted to ensure smooth Running of the engine.