Polished aluminium dashpot covers replace the standard black plastic caps on the suction chambers of the SU carburettors. The suction chamber is the large cylindrical body at the top of each carburettor that houses the piston and damper assembly.
The standard plastic cap is functional but visually plain, the polished aluminium replacement provides an attractive engine bay enhancement that catches the eye when the bonnet is opened.
Float Chambers Specification
Dashpot covers are available for both the HS2 (1275cc) and HS4 (1500cc) carburettors. The HS2 and HS4 covers are different sizes and not interchangeable. The covers thread onto the suction chamber in the same manner as the standard plastic cap, and the damper rod and oil are retained. No modification to the carburettor is required.
Throttle Linkage
When fitting polished covers, the damper oil level should be checked and topped up if necessary. The damper oil provides hydraulic resistance to piston movement, which controls the rate at which the carburettor responds to throttle changes, running without damper oil causes a flat spot on acceleration. The correct oil is a light engine oil (20W/50 is acceptable) filled to approximately half an inch above the top of the piston rod.