Which is NOT an indication of contamination damage in a vane pump?

Excessive shaft length is not an indication of contamination damage in a vane pump. The shaft length pertains to the design and size specifications of the pump and does not directly relate to the operational integrity of the pump's components due to contamination. When a pump experiences contamination damage, it typically manifests in the wear and tear of internal components due to particulates or debris circulating within the hydraulic fluid.

In contrast, signs like a frosted appearance on the vanes, marks around the inside of the cam ring, and circular marks on the flex plates are all indicative of wear resulting from contaminated fluid. Contaminants can create abrasive actions that lead to the surface degradation of vanes and other internal parts, producing visible signs of wear. Therefore, when assessing the condition of the pump and diagnosing issues, it is vital to distinguish mechanical design characteristics, such as shaft length, from signs of contamination damage.