Genuine 1986 Oldsmobile Cutlass Carburetor

1986 Oldsmobile Cutlass Parts Questions & Experts Answers

• Q: What are the key considerations and features of carburetors, particularly the Rochester 2G/2SE and 4MC Series on 1986 Oldsmobile Cutlass?

  A: It is not the author's purpose to find a carburetor which is compatible with a speci c vehicle; vital to record the number stamped on the carburetor unit and check with the parts-man, as using a di erent unit or modifying the jets or some internal component with one from a di erent manufacturer may cause problem. Automatic chokes are fitted on all units, stoveline from the manifold or electrically heated, while the carburetor may be the dual or four-barrel downdraft type in relation to the engine capacity. Repairing a worn carburetor is possible, although one should find or buy a repair set of gaskets and replaceable parts before starting work; if a carburetor looks significantly worn on the surface, it will be cheaper to install a new or remanufacturered one. The Rochester 2G/2SE Series carburetor is a dual-barrel side bowl type and includes units for manual and automatic transmission models, although physically very similar but calibrated differently. The main metering jets are not adjustable, but are calibrated by a series of air bleed holes, and a power enrichment valve assembly regulates mixtures of power in accordance with the velocity of air past the boost venturi in response with the engine requirements. In the later model vehicles, an electrically operated SO, Throttle Closing Solenoid is used to make sure that the throttle valve is closed, in order to eliminate running-on after the ignition is turned off. The automatic choke is the feature that is operated by an exhaust manifold heated coil. The Rochester 4MC (Quadrajet) Series carburetor is a downdaddle two-stage carburetor that comprises a primary side with a triple throat system and a secondary side that has two largeific bores and a compensatory system that adds to the prime main metering system and which is fed from a common float bowl. Another downdaft two stage Rochester M4M/M2M (Quadrajet) Series carburetor is similar to the 4MC unit.