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Have a question about my steering, 1955 clipper deluxe with power steering.
For some reason when I turn the wheel to the left it works great, but when I try turning right its "all arm strong steering". I rebuilt the power cylinder and the steering valve, drained the lines thought maybe an air blockage somewhere.
no luck... anyone ever had this problem?

You didn't mention if you have a Monroe or Bendix unit but on both, air on one side of the piston is one of the causes of hard steering in one direction. Another is the spool valve not being properly centered or having excess play at the neutral position so biased to one side giving priority in one direction. It could also be binding. Since you took the valve apart that area might be worth checking first. If a Bendix unit there is a service bulletin regarding centering the dust shield protecting the ball on the Pitman arm where it enters the control valve.packardinfo.com/xoops/html/downloads/STB/55T-38.pdf

Howard, thank you for your thoughts. There Bendix by the way. I downloaded the link you posted and I will check it out tomorrow.

Howard, having the car off the ground, moving the wheels back and forth there seems to be about 1/2" play at the tire and looking at the control valve ball it moves back and forth 1/4". Looking through all the service manuals I have they don't mention any play. Do you know if there should be any play? and how much is too much?


Thank you again,

Randy

There is play when the engine is off and that is the movement of the Pitman ball seat and valve in their bores. I believe the amount is determined by the components such as the cups, washers and shims or whatever is in the assy vs the length of the bore and how far the stop screw is threaded into one end. Don't remember if there is a dimension given for that movement but if everything is assembled correctly that would be the determining factor.

The hydraulic fluid is fed to either end of the spool valve which is attached to one side of the ball seat. As soon as there is pressure from the pump, for practical purposes the valve is fixed in position. Since it is connected to the seat the play goes away. As soon as you start to make a turn, due to the resistance of the road wanting to hold the housing and the pitman arm wanting to move the spool, the extra force on the spool disturbs the equal pressure slightly so the valve moves and starts to admit fluid to one end of the power cylinder and bleed off the other. During the turn, once the housing and steering wheel movement are in balance the spool returns to center and pressure is equal with no assist until you move the wheel to start coming out of the turn at which time everything starts again only in reverse.

Since you experience easy operation in one direction and hard the other I am wondering if the valve is in the same center as the seat movement. I believe it only takes a very small amount of change before the valve starts admitting fluid to the cylinder and if the valve is already close to one side it would need to move a considerable amount to reach the other before it could start admitting fluid for power to that side. I believe there are some directions on locating the spool valve on the rod so that when the ball seat is in the center of its travel the valve will also be in the center of its bore.

I have not compared the two in detail but in addition to the service manual there is a Servicemans training manual on the Bendix unit that was published when PS was made available. Even though it was for the initial 52-3 PS unit I believe the principles still apply to the 55-6 offerings with maybe some slight differences. Much better photos than the SM so there might be more visible info in it.packardinfo.com/xoops/html/downloads/PowerSteeringTrainingBook.pdf

Thank you again Howard, you gave me a wealth of information that I couldn't find.
I will dig into it and hope to find a solution.




UPDATE:
ended up picking up a rebuilt control valve unit, installed it and things are working great.

Thanks randy