A/c Compressor General Specifications - r-4 Chevrolet Camaro II

R-4 COMPRESSOR DESCRIPTION

The Harrison 4-Cylinder Compressor is a radial-design unit, built by the Harrison Radiator Division of General Motors. Known to the industry for many years as the Frigidaire, General Motors or Delco-Air R-4 compressor, it is now available under the Harrison name in its original design, as well as in 2 other variations.

For example, in 1982 General Motors "A" body cars with V6 diesel engines first used an R-4 compressor with a poly-groove drive pulley instead of the original "V" pulley. A second variation, used on 1984 Corvettes and "S" Series Trucks, teamed the R-4 compressor with the 6-pole clutch of the Harrison DA-6 compressor.

The basic compressor remains unchanged, featuring a modified yoke with 4 cylinders located radially in the same plane. Opposed pistons are pressed into a yoke, which rides on a slider block on the shaft eccentric.

Rotation of the shaft provides piston motion without connecting rods. No oil pump is used, as compressor lubrication is provided by piston movement. Reed valves for suction and discharge are provided for each cylinder.

Protective devices, used with the R-4 compressor may include

1. A pressure relief valve, providing pressure bleed off under high pressure conditions.
2. A superheat switch and low pressure switch, designed to stop compressor operation if refrigerant charge is too low.
3. A high pressure switch, which shuts down the compressor when system pressure is too high.
4. A fan pressure switch, that energizes the cooling fan when system pressure is excessive.

COMPRESSOR TOOL REFERENCE NUMBER APPLICATIONS

HARRISON 4-CYLINDER COMPRESSOR

OVERHAUL

Note. For overhaul procedures for the Harrison R-4 compressor, refer to R4 OVERHAUL - EXC V-BELT or the R-4 OVERHAUL - W/ V-BELT articles in this section. These articles will explain shaft seal, pulley bearing and clutch coil replacement procedures for the 3 variations. A chart, listing special tools required for servicing the R-4 compressor variations also accompanies these articles.

Exploded View of Harrison R-4, 4-Cyl. Compressor (Original Design) Other R-4 variations include V-Belt/Poly-Groove drive pulley or 6-pole clutch type. Scheme 108