Component Tests and General Diagnostics

CAUTION: BRAKE FLUID MAY IRRITATE EYES AND SKIN. IN CASE OF CONTACT, TAKE THE FOLLOWING ACTIONS:
^ FOR EYE CONTACT, RINSE THOROUGHLY WITH WATER.
^ FOR SKIN CONTACT, WASH WITH SOAP AND WATER.

CAUTION: Avoid spilling brake fluid on any of the vehicle's painted surfaces, wiring, cables or electrical connectors. Brake fluid will damage paint and electrical connections. If any fluid is spilled on the vehicle, flush the area with water to reduce possible damage.

NOTE:
^ Use only Delco Supreme 11(R) Brake Fluid, GM P/N 1052535, or equivalent DOT 3 brake fluid.
^ Do not use power steering or transaxle fluid in the brake system.
^ Do not reuse brake fluid collected during system bleeding.
^ Always store brake fluid in a closed container. Reseal brake fluid containers immediately after use. Do not use brake fluid left in an open or improperly sealed container because it absorbs moisture or can become contaminated.

Improper brake fluid, mineral oil (i.e., power steering fluid and transaxle fluid) or water in the fluid may cause the brake fluid to boil or the rubber components in the hydraulic system to deteriorate.

If the primary piston cups are swollen, then the rubber parts have deteriorated. This deterioration may be evidenced by piston cups on the drum brake wheel cylinders, or substau1dard or contaminated brake or master cylinder cover diaphragm.

If deterioration of rubber is evident, disassemble all hydraulic parts and wash with alcohol. Dry these parts with non-lubricated compressed air before assembly to keep alcohol out of the system. Replace all rubber parts in the system, including hoses. Also, when working on the brake mechanisms, check for fluid on the linings. If excessive fluid is found, replace the linings.

If master cylinder piston seals are satisfactory, check for leakage or excessive heat conditions. If condition is not found, drain fluid, flush with brake fluid, refill and bleed system.

The system must be flushed if there is any doubt as to the grade of the fluid in the system or if fluid has been used which contained parts that have been subjected to contaminated fluid.