Can I Rebuild My Ford Pump

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The End Plate sets between the Front Housing and the Cam Pack. The surface is sometimes scored by the Rotor and Slippers of the Cam Pack, but it is most often damaged by the flange on the Input Shaft. The End Plate acts as a forward thrust surface for the Input Shaft and this flange makes contact with it. If the pump is run low on fluid, the flange of the Input Shaft will score the End Plate, shedding metal and increasing the Input Shaft end play. An End Plate damaged in this way must be resurfaced or replaced.
The Pressure Plate sets between the Cam Pack and the Pressure Valve or Separator Plate. Like the End Plate, it can be scored by the Rotor and Slippers. It also acts as the rearward thrust surface of the Input Shaft. Any scoring of the Pressure Plate will shed metal into the pump and increase the Input Shaft end play. A Pressure Plate damaged in this way must be resurfaced or replaced.

Although the Pulley is not a part that normally needs replacement during a pump rebuild, it is a part often damaged during the rebuilding of one. The Pulleys on all Ford/Thompson pumps are pressed onto the Input Shaft. The Pulley has a special hub in its center that is designed for special tools for removal and installation on the shaft. It is HIGHLY recommended that these proper tools be used to R&R the Pulley to avoid damaging it during the course of a rebuild.

Often an aftermarket pump will come with a nut, bolt and washer arrangement used to press the Pulley onto the Input Shaft. While we still recommend that the proper tool be used to install the Pulley, this setup can be used if care is taken during installation. The most common malfunction of using this setup is that the bolt may break off inside the Input Shaft, requiring a trip to a machine shop for removal of the bolt and repair of the threads before another attempt can be made.
You cannot drive the Pulley onto the shaft with a hammer or press. This will push the Input Shaft into the pump, forcing it against the Pressure Plate, causing it to break.

The most common situation is trying to remove the Pulley from the shaft without the proper tool. This tool is designed to surround and grab the hub at the center of the Pulley, and it concentrates all its force on this area. No stress is ever placed on the flanges of the Pulley. Use of a common style gear puller on the outer flanges will only bend them and ruin the Pulley for further use. Trying to use a gear puller on the pulley hub will only cause it to distort the hub flange and slip off.
You cannot press the Pulley off of the shaft using a press and a bearing removal tool. This puts stress on the belt flanges of the Pulley which will bend and distort.
Only use the proper tool to remove the Pulley from the Input Shaft.

If you buy a rebuild kit that is complete with Slipper Springs and a good set of instructions, the surfaces of the Input Shaft, Cam Pack Housing and Slippers, End Plate and Pressure Plate are not damaged, the Reservoir is not damaged to where it will leak or not fit properly, the Input Shaft Bushing is not damaged or worn, and you have the special tools to remove and replace the Pulley without damaging it - then you can probably rebuild your Ford pump.
If not, or the pump has low pressure or makes noise, it may be best to leave the rebuild to a professional.

If you are in the middle of a rebuild, or are thinking of doing one on your own, we will be glad to help you as best we can. Because we are busy rebuilding during the day, we cannot always help you by phone. But if you send us an email with a description of your problem, we will try and get back to you within 24 hours.

Keep in mind that few parts besides those seals and gaskets included in a typical rebuild kit are available new. Those that are consist of the Slippers, Slipper Springs and Input Shaft Bushing. Some pulleys are being reproduced and are availble. New Cam Packs are available but only the later style "thick" models. These cannot be used in early pumps with the "thin" style packs without also installing the matching input shaft and front end plate.

Many of the parts inside a Ford Pump are the same or will interchange. Usually, the main differences between the pumps of different years or car lines is the design of the Reservoir and the settings of the Pressure Valves. While some cars, such as Galaxies and T-Birds, may have used a Pressure Valve that allowed more pressure throughout the system, these valves and pumps will still swap between cars with no problem. In fact, most pumps have been replaced at least once with an aftermarket rebuild in which little if any attention was paid as to what Pressure Valve was used. Though there were several different styles of Pressure Valves used during production of the Ford Pump, they are not marked or coded in a way that they can be identified or their pressure setting determined.

The most common problem with a Pressure Valve is that the actual valve inside will stick, usually in an open position. This will cause the valve to bypass fluid back into the Cam Pack, causing low pressure in the system. The valve can stick because of varnishing of the fluid due to excessive heating or because a small piece of debris has jammed it. It may be possible to free up the valve and get it working again, but care must be taken not to force the valve or its sharp edges can shear metal shavings into the valve. It is difficult to disassemble the Pressure Valve, so repair may not be possible. Although not common, sometimes the housing of the valve will warp and lock up the valve. Because of the difficulty in freeing a sticking valve, and the chances to cause further damage, it is often better to replace a faulty valve than to repair it.

There are several different designs of Pressure Valves used in the Ford/Thompson Pump. Each looked the same from the bottom (as pictured to the right) and functioned basically the same. All had a spring-loaded valve and retainer to hold them in place. The Pressure Valve was not meant to be disassembled or rebuilt.