A/T - Rapid Converter Pump Bushing Wear

TSB 86-1 (Jan)

SUBJECT: CONVERTERS

PROBLEM:







RAPID pump bushing wear on suction side of bushing, after converter replacement, or hub sanding (Figure 1)

CAUSE:
There are several possible causes: Defective bushing, crooked installation, poor lube, etc., - The most common cause (and it seems to be increasing across the continent) is rough converter hub finish. Rough finish, or scratches in the hub, act as a file against the bushing. Suction on one side of the pump, opposed to pressure on the other side will always tend to push the converter hub to the suction side of the bushing.

SOLUTION:
Visual checking is not always enough, but be sure to look for scratches. The simplest, yet most effective way, is to run the tip of your fingernail, in a scratching stroke, down the hub, as indicated by the arrow (Figure 1). The hub is too rough, if anything is felt at all. Sand around the hub in the direction of the converter rotation with 1100-600 grit "wetted" paper. (Solvent, or transmission fluid work well).

Hubs must have a mirror finish, and be smooth as glass to insure maximum bushing and seal life.