HPP-19204 is the part number we use for the OEM Powerglide pump (gear side) front halves that we remanufacture in house.
After the pumps have been cleaned and vapor honed, we do perform an inspection process on the gear cavity. During the inspection process these cores were found to have a worn gear cavity so they could not be rebuilt with a standard OEM gear set. Once this condition is found we determine if pump half has enough thickness to proceed to our OSK process. Cores that met the criteria, have the surface that mates with the rear pump half turned true in the lathe and have the gear cavities CNC machined to suit the aftermarket oversized gear set. After a final wash the cores are routed through the same process as our HPP-19203 cores; the front face is painted, we install a new torque converter to pump bushing, new front seal, and a new aftermarket OSK gear set. We verify gear clearances are within specification again just before we bag and box the pumps.
Our machining process ensures all critical surfaces and cavities are parallel and perpendicular to one another which based on our inspection process is not something that GM did back in the day.
