Friday, October 18, 2013

Power Play - Pump It Up!

Okay, now that I have a control valve to control my power steering and a power cylinder to power my power steering, I needed something to squish the power steering fluid (Type F ATF, actually) into the control valve and power cylinder and what better way to squish fluids into things than with a pump?   Fortunately,  I had made a deal with a VMF member to buy the entire power steering system including the pump and bracket(s).  Unfortunately, the pump was in no better condition than the cylinder or control valve and was in desperate need of a rebuild.  Well, I'm not sure it qualifies as a "rebuild" per-se because I didn't replace any of the mechanical parts of the pump.  Rather just some spit-n-polish and some new seals placing my faith in the car-gods to protect me.  Additionally, I attempted to assess the condition of the assembly by making sure it rotated smoothly, without binding, and that there was no discernible slop in the input shaft.  That all felt good to me so I forged ahead.

The first part I felt the need to remove was the pulley.  This was accomplished with, what else?  A pulley puller.  There's a protrusion on the front that is intended to be used to pull the pulley off without damaging it.  The pulley puller has wider jaws than a regular gear puller.  I had attempted to use a gear puller and failed when the narrow jaws just slipped and chipped off chunks of the puller flange edge.  I wandered down to Harbor Freight and bought the Automotive Pulley Puller.  After some sweating and cursing at the puller jaws popping off of the flange, I clamped the end of the puller jaws onto the flange with a C-Clamp so it wouldn't slip off and succeeded in removing the pulley.

I could then get to the bolts of the pump bracket and remove the bracket from the pump housing.  I then turned the pump over and removed the nut from the high pressure output nipple along with it's id tag.  The pump can was then free to be pulled away from the pump assembly.  There was one seal washer between the can and the pump.

In the beginning...

Come.... ON... get.... OFF!!

The bracket could then be removed.

The nut removed from the pump outlet

The can has been removed.  This washer prevents leaking from the base of the pump outlet.

Pulled apart.

Four bolts could then be removed and the back of the pump was removed to expose a stack of pump parts that were kept in place via two locating pins.  The stack of parts just lifted off of the pins until the end of the input shaft was found nestled deep within the pump rotor.  The shaft could then be pulled up and out of the front pump plate.  Since the end of mine was rusted a bit from exposure, I had to polish it with a wire wheel to allow it to be pulled out through the front bushing.

Removing the inner can from the pump front.

Split apart

Unstacking the pump rotor assembly

Looking in at the rotor

How the rotor is removed from the front plate.

Pulling the input shaft out of the front plate.

After the shaft was removed, the front seal could be popped out.

Removed the front seal.  Make sure the bushing beneath is still serviceable.

 Next the pump stack was thoroughly cleaned and pre-lubed with ATF and then reassembled in the exact same orientation using several pictures I took of each part being removed.  The input shaft was polished using a brass wire wheel and steel wool.

Removing the relief valve from the inner can

Rusty shaft

Cleaned up shaft

Probably the most puzzling part of the re-assembly was the placement of two springs in the bottom of the pump can onto which the relief valve puck was placed.  If the springs toppled over, the puck would have to be removed and another attempt be made.  I re-assembled the pump kind of backwards from how I took it apart. That is, I stacked the parts in the can then mated the shaft and pump front onto it.

The ends of the springs go into those round protrusions

Relief valve puck installed.  Note the alignment of the slot in the side of the can in relation to the ports on the puck.

Rotor assembly installed.

The pump housing was then cleaned up, primered, and painted semi-gloss black.  Now calm down, I DID research the correct factory color of the 68 power steering pump and what I came up with was... well... I found a VMF thread that debated it a bit.  You read it and choose your own pump color.  What I came away with was that it was just as likely that you get a black pump from the factory as a teal/blue pump so that's what I went with since I had black paint handy, needed to paint it NOW, and didn't want to wait for the factory correct color... so there.  If you have the time to wait, the consensus of respectable Mustang gurus on the web is that NPD has the closest match.

Aaaanyway, after the housing was painted, I drove in a new front seal.  If you have any play in your input shaft, replace the bushing as well.  I didn't, so I didn't.

UPDATE 3/20/2015: It's been pointed out to me that if you've gone this far, you may as well replace the bushing.  I was admittedly lazy with this step.  In order to truly assess the condition of the bushing would likely require the use of a micrometer.


Self-etching gray primer.

Semi-gloss black engine enamel

New seal inserted

Oh yeah, speaking of the front seal, it came in a seal kit that I bought from NPD.

Mating the front of the pump to the inner pump can.

Touch down.  Torqued.   Note the alignment of the intake slot against the slot in the edge of the relief valve puck.

Assembled pump

New can ring gasket
 When the outer pump can is placed against the front plate, there's a particular way it has to be indexed.  It will fit in ANY direction but has to be installed in just one orientation.  The key is to have the intake slot on the inner pump can facing down.

Inserting the outer can onto the pump.  The input slot on the inner can wall faces down.

Tightened down the pump outlet nut.

Installed the freshly painted bracket.  Notice the orientation of the ridges on the pump front casting in relation to the fill tube.  This orientation is important.

After the pump was re-assembled, the pulley needed to be pressed back onto the shaft.  The inside of the shaft is threaded so I stacked up some greased washers and a socket and pressed the pulley back onto the shaft so that the end of the shaft was flush with the puller flange.

Pressing the pulley back on



The pump was then deemed ready for service.  Now I just have to see if they can all work together as a team.

Sunday, October 13, 2013

Power Play - The Power Cylinder

 Here we are in day 16 of the US Federal shutdown and we all know it's about power and control.  About steering the system in particular direction despite what the subjects want.

Speaking of power steering control, I have a pretty, newly rebuilt, control valve but nothing yet to subject to it's control and what good is control if you have nothing to control?   Enter the power cylinder.  This is the hydraulic ram that forces the center link to one side or the other depending on which way the steering wheel is turned.  Unfortunately, there's isn't much that can be serviced on these power cylinders.  You can replace the boots and seals and that's it.  You can't refurbish the plunger inside the cylinder or even the center link ball stud on the back end.  So, that's all that's really needed on this task so I'll go over it here.

 The first thing is the removal of the center link ball stud boot.  This just involves removing the clamp and working the boot back up and over the end of the cylinder.  Mine was badly hardened and pretty much just split.  Sadly there's also no way to replace the grease in the ball stud socket.  I pretty much left it alone because I didn't want to remove the grease in there with no way to replace it.

Next, I gently supported the cylinder in my bench vice and removed the nut from the end of the cylinder arm and worked the old bracket and rubber bushings off the threads followed by the remnants of the flexible dust boot.

Clamp removed, ready to pull off the boot.

Dryed out and cracked.

Removing the frame bracket.

It's off!

I then took the cylinder to my brass wire grinder wheel and removed the years of rust and grime.  When the dust settled, what I was rewarded with was the very prominent dent in my power cylinder.  I hadn't noticed it earlier due to the dirt and grime.  I ran the arm back and forth and felt an obvious bind in the action so this cylinder is officially unusable.  I could buy a refurbished cylinder for around $140 but I already had the seal kit and replacement boots and bushings plus I had an extra power cylinder.  The one that I had received with the package deal I'd bought for my disk brakes over four years ago.  Part of that deal was the power steering assembly from a 71 Ranchero.  The other parts in the set were not usable (other than some control valve parts) but the power cylinder looked pretty much identical so I set to work tearing it down in the same way I had done the previous one.   Sadly, this one too had some small dings in the cylinder housing.  I panicked a little as I tested the action of the arm and could feel no binding so I shrugged and forged ahead.

Aw crap... a dent.  This cylinder is unusable.

Removing the 71 Ranchero cylinder frame bracket.

It helped to clamp the flattened end of the arm in a vice to loosen the nut.

The bracket removed.

The cylinder ready to be refurbished.  Also has some dings but is still usable.

The replacement of the seals is a pretty straight-forward removal and re-insertion of a stack of 7 parts, each included in the rebuild kits available.  The whole stack is held in with a single snap ring.  The rest can be worked out of the housing with a dental pick or similar.

Removing the snap ring and "scraper"

The rubber wiper

Removing the rubber wiper

The retainer

Removing the retainer.  This was actually kind of difficult.

Seal #1
Insert between Seal 1 and Seal 2

Seal 2 visible.  This one was tough to remove.  I had to drill little holes in it to pull it out.

Whew, got them all out.
The abyss

Seal 1 going in

I used a length of pipe to gently seat the seal

Insert between seal 1 and seal 2

Seal 2 going in.

Seal 2 in

Retainer inserted

Rubber Wiper


Snap ring

The new center link ball stud boot can be lubricated up and slid and stretched over the end of the power cylinder (which I had just cleaned up with the wire wheel and painted with several coats of clear lacquer). The end boot clamp can then be installed.  Remember to slide the clamp onto the cylinder before the boot.  I hadn't and had to remove the boot and do it again.

Work it over the end.  Oops.. is that the clamp sitting on the bench there?

Boot and clamp installed.

The flexible arm boot was then slid down over the arm.  It helped to lubricate the small end.  The large end just has a lip that catches in a groove on the cylinder housing without a clamp.  I re-punched 4 holes in the large end of the boot to allow air to flow in and out like an accordion.  I then placed and tightened the arm clamp.

Flexible boot in position

End clamp in place, testing extended position.

Testing compressed position.

Finally, the frame bracket could be affixed to the end of the arm via the stack of plates and rubber bushings tightened on with a nut followed by a lock nut.

Control valve and power cylinder.

I then replaced the two hose seats in the same manner as I had done for the control valve.  I coated a 1/4 20 tap with grease to hold onto the chips while I threaded the old hose seats, screwed in a 1/4 20 bolt and yanked them out.  I then lightly pushed in the new hose seats.

Grease up a tap and tap the seat.

Thread in a 1/4" bolt

Pop out the seat.

Awaiting a new seat.

New seats in installed.

This task was then complete.  Now, if only there was a way to pressurize the power steering fluid... hmmm...