Diesel Data: Automotive Repair

Installed


1. Connect manifold gauge set to compressor.
2. Run engine at fast idle and check low pressure gauge reading.
a. Pressure gauge readings below 7 psi. are caused by moisture freezing in the expansion valve orifice or by gas leakage from capillary tube or bulb. Check or replace expansion valve or receiver/drier.
b. Pressure gauge readings above 70 psi. are caused by excessive opening of the expansion valve orifice, which is due to a loose remote bulb holder or a defective expansion valve. Retighten or replace bulb holder or replace expansion valve.