For 1990-2009 cars

# Info - Water Pump Weep (Normal Condition)

Subject: | Water Pump Weep (Normal condition)

Models: | 1996-1998 Buick Skylark

| 1996-2001 Chevrolet Cavalier

| 1997-1999 Chevrolet Malibu

| 1996-1998 Oldsmobile Achieva

| 1999-2001 Oldsmobile Alero

| 1996-2001 Pontiac Grand Am, Sunfire

| 1996-2001 Toyota Cavalier

| with 2.4 L Engine (VIN T -- RPO LD9)

Many coolant pumps may show a staining around the weep hole. This staining may be the evidence of normal coolant weepage. The weep hole permits the seal to breathe, allowing for expansion and contraction of the fluid and air around the outside of the seal assembly. This area of the pump housing provides a drain path to keep the bearing assembly seal dry. The weep hole also allows vapor to clear from the area to prevent crystalline formation. The seal face load springs control a balance of the hydrodynamic film required to lubricate the seal. As the pump stops turning, the spring squeezes most of the coolant from between the faces. This is known as weepage and is normal for automotive seals. It is normal for a drop or two of coolant to appear at the weep hole. It is not necessary to replace the coolant pump for weepage if you are working on the front of the engine and you notice a drop or a stain.

The best tip is to be sure your diagnosis and repair is driven by the customer's concern. Follow Service Manual diagnostics. If the customer is actually seeing drops of coolant on the driveway, and you suspect the coolant pump, confirm your diagnosis with a pressure test of the coolant system and replace the pump if necessary.

Finally, any time the coolant pump is serviced, or any other service is performed that requires removing the timing chain on the 2.4 L engine, it is critical that the chain tensioner reset procedure is followed correctly. Use the Service Manual procedure to release the timing chain tensioner. If the timing chain tensioner plunger is not released from the installation position, engine damage will occur when the engine is started.