PSC Hydraulic Steering Assist System
By Jack Brinks

Time for the new PSC pump.  Carefully mount the snout end of the new pump in the vise and install the two mounting studs.  Put the nuts on to avoid damaging the threads, invert the pump, and then clamp the studs/nuts in the vise firmly.  Place your old pulley on the pump, and use your pulley installer to carefully force the pulley onto the pump shaft at the same depth as the original.  If applicable, don’t forget to install the front portion of the pump bracket first!

If you haven’t already, install the new gear, hooking up the steering shaft and tightening down the lines, making sure they’re routed properly to clear other components.  Next, reinstall the new PSC pump, installing high and low pressure lines, and tightening the belts to spec.  Whatever you do, DO NOT pry against the soft pump main reservoir!  Use a wrench on the boss cast into the pump. That’s what it’s there for!

Once you’ve got the new PSC gear and pump installed, you’ll have to figure out where to mount the remote reservoir.  It obviously needs to be relatively close to the pump, and should be higher than the pump if at all possible to make bleeding air from the system easier.  As you can see, I elected to fabricate a small bracket that bolts down using one of the intake manifold bolts and bolts to the reservoir bracket itself.  This allowed me to use the PSC supplied hose, with the 90 degree fitting screwed into the side of the reservoir, and the straight fitting going into the main pump reservoir.  

While you’re in this area, you may as well go ahead and plumb the remaining low pressure lines.  This is a good time to consider adding a power steering fluid cooler, if you haven’t already.  There are many types available, and I chose to continue to run the same one I have for years, mounted to the front of the electric pusher fan sitting in front of the radiator.  Another thing to consider is the use of synthetic power steering fluid, such as Royal Purple’s Max EZ, which runs significantly cooler.   Either way, connect the low pressure line from the power steering gear to the bottom of the remote reservoir, using the PSC supplied hose and fitting.

Now, the fun starts!  You’ve probably already thought about this, but you first need to figure out the right way and place to mount the hydraulic cylinder (ram).  And, this is where I get to admit that my first attempt was definitely the wrong way!  My hesitance to weld to cast iron got me in trouble. What can I say? 

Anyway, we’ll get back to that in a bit.  As you could see from the “before” photos, I had decided to mount my tie rod behind the differential, out of harm’s way.  After assembling the heim joint ends to the ram, and figuring out the half-way mark for the travel of the ram rod, I got out the Sharpie marking pen to mark the location of both the fixed end of the ram and the working end.  In my first attempt at this, I was using two of the including weld-on mounting tabs to mount the fixed end, and a prototype tie rod mount that PSC had supplied me with.  This threaded tie rod mount is a beautiful piece of machining!  Once the mount locations were determined, I tack-welded the fixed end mounting tabs in place and then the tie rod mount.       

Once I installed everything again to verify clearances, I called the tech folks at PSC, as I was a bit concerned about the angle of the ram.  They explained that a small amount of angle was usually OK, but that the more parallel the ram is to the tie rod, the better.  I had more than a small amount, but felt it would work, so I finished welding and painting, eager to get done so I could try this new “toy” out!  This Jeep hadn’t been on the trail in a long time. I was more than ready to go ‘wheelin’!

The last thing to do is to “build” the high pressure lines that go from the ports tapped into the new PSC steering box to the hydraulic cylinder.  The steel reinforced hose comes in one length, and must be cut (I used a hacksaw) to fit your application.  Remember to allow for travel of the axle, and clearance of suspension and other components when determining length.  After some careful inspection and measuring, I decided to just cut the hose in half, figuring that I could always shorten it in the future.  Since these high quality hose-end fittings are reusable, this would be no problem at all.  Basically, all that’s required is to “thread” the hose into the large outer fitting, with the inner fitting threaded almost all the way out. 

Suggestion:  Clamp the large outer fitting in a vise in a position that allows you to thread the hose into it by hand.  Don’t be shy, thread as far as it will go.  Then, reposition the fitting so you can use the appropriate wrench to tighten the inner fitting all the way down, as shown in the photo. 

 

CONTINUED   PAGE 3 --->>>