For 1990-2009 cars

# Coolant Leak (Repair or Replace Coolant Cap)

Subject: | Coolant Leak (Repair or Replace Coolant Cap)

Models: | 1999 Chevrolet Cavalier, Malibu

| 1999 Oldsmobile Alero, Cutlass

| 1999 Pontiac Grand Am, Sunfire

| 1999 Toyota Cavalier

| 1999 Chevrolet & GMC C1/K1 Models (Silverado & Sierra)

### Condition

Some customers may comment on the following conditions:

• | Coolant leaks

• | The low coolant light is ON.

• | Overheating or no heat

• | Odors coming from the air conditioning system.

• | No start

### Cause

The check valve in the coolant pressure cap may not work properly. The valve may not have been centered correctly when the cap was assembled by the vendor.

### Correction

Caution: With a pressurized cooling system, the temperature of the coolant in the cooling system can be considerably higher than the boiling point of the solution at atmospheric pressure. Removal of the surge tank cap, while the system is hot and under pressure, causes the solution to spew out over the engine, the fenders and the person removing the cap. Serious bodily injury may result.

Inspect the coolant recovery cap pressure relief valve for correct operation, using one of the following procedures ("A" or "B" below):

### Service Procedure "A"

Using the cooling system pressure tester J 24460-01 and adapter J 42401-1, follow the steps below:

1. Remove the cap from the surge tank (coolant reservoir).
2. Inspect for the presence of (2) O-rings around the outside of the cap mechanism. If not present, replace the cap with P/N 22652695.

If the cap fails the test, firmly press on the center of the valve with the eraser end of a pencil. Compress the spring about 6-7 mm (¼ in) and release. This should center the valve.

3. Retest. If the cap fails again, replace the cap with P/N 22652695.

### Service Procedure "B"

If the special tools in Procedure "A" are not available, follow the steps below:

1. Remove the cap from the surge tank (coolant reservoir).
2. Inspect for the presence of (2) O-rings around the outside of the cap mechanism. If not present, replace the cap with P/N 22652695.
3. Place the cap on a bench with the label down. Fill the center, above the brass valve, with water. If you can completely fill the center section and it holds the water, the valve is working properly. If the water drains from the center section, firmly press on the center of the valve with the eraser end of a pencil. Compress the spring about 6-7 mm (¼ in) and release. This should center the valve.
4. Retest. If the water is now retained by the center section of the cap, the cap is repaired. If not, replace the cap with P/N 22652695.

### Parts Information

Part Number | Description
--- | ---
22652695 | Cap, Coolant

Parts are currently available from GMSPO.

### Warranty Information

For vehicles repaired under warranty, use:

Labor Operation | Description | Labor Time
--- | --- | ---
J3020 | Cap, Radiator Filler - Replace Includes pressure testing cap | 0.2 hr