Engine Cooling - Coolant Pump Replacement Issues

S303-15

S-TYPE

DATE 03/03

MODEL
2000 MY-ON
S-TYPE

VIN
L00001-ON

Coolant Pumps - Impeller Material - Pump Replacement Issues

Issue:

A large number of V8 coolant pumps are replaced unnecessarily for the following reasons:

^ routinely following an engine overheat condition,

^ incorrect diagnosis of leakage, or

^ incorrect identification of impeller material.

As a result, a significant proportion of warranty returns have been identified with no fault found.

Dealers are assuming that because the coolant pump has a black impeller it is made of Nylon 66 and must be replaced.

These pumps should not be replaced as a matter of policy, since coolant pumps with Nylon 66 impellers have never been used in production S-TYPE V8 vehicles.

Action:

Note:
Do not automatically assume that a black impeller is made of Nylon 66.

Do not replace S-TYPE V8 coolant pumps purely because they have a black impeller. These impellers are made of poly phenyl sulphide not Nylon 66.

Note:
Do not assume that staining around the exterior of the coolant pump body is due to a coolant pump leak. Check the cooling system joints for leaks in the area above the coolant pump. For any cooling system issues follow the workshop procedure as detailed in (JTIS) for diagnosis and testing of the cooling system.