Power Steering Pump Rebuild

This update will detail the process involved with rebuilding the power steering pump. Originally I was going to wait and do this later, but since the alternator pulley is driven off the power steering pump pulley it was necessary to complete the rebuild now so that I could reinstall the power steering pump and properly set up the pulley system.

To complete this task I purchased a rebuild kit from Zip Products. The kit covers a number of different pump models and had several unneeded o-rings and bushings, but it did come with decent instructions so it wasn’t too confusing. I also referenced the Chassis Overhaul Manual which had some good descriptions and pictures of the work. So, time to get started! Here’s the power steering pump with the pulley removed, power steering fluid drained, and most of the grease and grime removed.

Copyright - Tim Cote 2007
To facilitate disassembly the power steering pump was secured in a vice and the stud was removed from the back of the reservoir.

Copyright - Tim Cote 2007
Next the pressure union was removed…

Copyright - Tim Cote 2007
As well as the flow control valve and flow control valve spring (these are located inside the pump housing – below the pressure union).

Copyright - Tim Cote 2007
Next the reservoir was separated from the pump body by tapping on the flanged edge of the reservoir. It only took a few light taps, anything more and a wood block would need to be used to prevent denting the reservoir.

Copyright - Tim Cote 2007
  
Copyright - Tim Cote 2007
After a good degreasing, cleaning and paint removal the pump reservoir was ready for primer and paint.

Copyright - Tim Cote 2007
  
Copyright - Tim Cote 2007
Next I moved onto the pump housing. To start I rotated the end-cover retaining ring so that the end of the ring was near the access hole in the pump housing (In the photo I’m pointing toward the access hole with the punch).

Copyright - Tim Cote 2007
With the ring rotated into position I inserted a small punch through the access hole to force the ring out of its groove. A screwdriver was then used to pry the retainer ring out.

Copyright - Tim Cote 2007
With the retainer ring removed the end cover easily popped out and was removed. As shown in the photo, there is a spring below the end cover which helps to pop it out of place.

Copyright - Tim Cote 2007
Next the pressure plate, dowel pins and cam ring were removed. Once those were removed from the pump housing the shaft, thrust plate and rotor were removed by gently tapping on the end of the shaft (remember to remove the woodruff key from the pulley first). The shaft, thrust plate and rotor come out as a complete assembly.

Copyright - Tim Cote 2007
Here are all of the internal parts of the pump (except for the o-rings which are not pictured). At this point I thoroughly cleaned all of the parts with solvent and dried them prior to reassembly. Prior to reassembly I checked the condition of the pump shaft and the shaft bushing, luckily for me both were in good shape and replacement was not necessary.

Copyright - Tim Cote 2007
Here the old shaft bushing is being removed from the pump housing prior to cleaning and painting.

Copyright - Tim Cote 2007
  
Copyright - Tim Cote 2007
Well, here’s that new seal kit I purchased. As I mentioned, not all of these seals are used in the rebuild since some are for different pump models.

Copyright - Tim Cote 2007
To start I installed the new shaft bushing. A large socket was used to drive the bushing firmly and squarely into place..

Copyright - Tim Cote 2007
With the new bushing in place I once again secured the pump housing in a vice, reinstalled the two dowel pins, and lowered the shaft/rotor assembly into place. During reassembly all parts were lubricated with Automatic Transmission Fluid (a suitable substitute if power steering fluid is not available).

Copyright - Tim Cote 2007
Next the cam ring was installed (pay careful attention to it’s orientation when installing) followed by the pump vanes. The pump vanes should be installed with the rounded edges toward the cam ring.

Copyright - Tim Cote 2007
Following the installation of two new O-rings in the pump housing, the pressure plate was lubricated and reinstalled. Firm finger pressure was required to seat the pressure plate squarely against the cam ring.

Copyright - Tim Cote 2007
With the pressure plate spring in place the end cover was installed and pressed down into place so that the end cover retaining ring could be snapped into place. The ring should be installed so that the gap is near the hole for the pressure union.

Copyright - Tim Cote 2007
Here the flow control valve and flow control valve spring are being placed back into the housing. Don’t forget to clean the filter screen at the end of the flow control valve before reassembly!

Copyright - Tim Cote 2007
Prior to installing the pump reservoir I installed two new mounting stud seals, a new pump body to union seal and a new reservoir to pump housing O-ring (locations are shown by yellow arrows in the photo below). With the new O-rings in place the reservoir mating surface was lubricated and then the reservoir was pressed into place over the pump housing O-ring.

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With the reservoir in place a new O-ring was installed on the Union, and then the union and stud were installed and tightened down. However, note that I actually have the O-Ring in the wrong groove in the photo below. However, please note the O-Ring should actually be in the upper groove of the union (the one closer to my thumb), not the lower groove (closest to the threads)! This was later fixed after a power steering leak developed.

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Here’s the finished pump. All there’s left to do is install the woodruff key, pump pulley and a new pulley nut which will need to be torqued to 60 ft. lbs. It doesn’t look brand new, but it sure is a lot better than it was!

Copyright - Tim Cote 2007
  
Copyright - Tim Cote 2007
Well, that’s it for now. Look for another update soon!