Hej! Här framgår varför det är 2 anslutningar och hur det skall kopplas! Dual Diaphragm Distributors Dual diaphragm distributors are installed in most 1968 and later models. They appear in many different engine/transmission/equipment combinations. The dual diaphragm is a two-chambered housing which is mounted on the side of the distributor. The outer side of the housing is a distributor vacuum advance mechanism, connected to the carburetor by a vacuum hose. The purpose of the vacuum advance is to advance ignition timing according to the conditions under which the engine is operating. This device has been used on automobiles for many years not and its chief advantage is economical engine operation. The second side of the dual diaphragm is the side that has been added to help control engine exhaust emissions at idle and during deceleration. The inner side of the dual diaphragm is connected by a vacuum hose to the intake manifold. When the engine is idling or decelerating, intake manifold vacuum is high and carburetor vacuum is low. Under these conditions, intake manifold vacuum, applied to the inner side of the dual diaphragm, retards ignition timing to promote more complete combustion of the air fuel mixture in the engine combustion chambers. Det kan vara så att det finns en temperaturstyrd vacuumventil i termostathuset också, och då skall den yttre anlutningen till denna ventil,se bilaga.