C3 Power steering control valve replacement

[Gary V.]

I'm going to replace the power steering control valve assembly. The one on the car is beginning to leak at the ball stud seal. I just bought a new, not rebuilt unit. Any tips or advice for this job?
Gary

[Christopher K.]

Re: C3 Power steering control valve replacement

Gary,
I'm sure you'll get lots of great advice soon but I'll offer you one tip. Count the number of turns it takes to remove the old control valve. Then when you put on the new one you turn it the same number and it will be in the same position, very important. You'll also want to bleed all the air from the system after the install and adding the fluid. Jim Shea on the CF has some detailed documents to help with the process.
Good luck,

[John H.]

Re: C3 Power steering control valve replacement

I'm going to replace the power steering control valve assembly. The one on the car is beginning to leak at the ball stud seal. I just bought a new, not rebuilt unit. Any tips or advice for this job?
Gary

Gary -

When you get to the point where the valve is re-installed and you're ready to bleed the system and balance the valve, DO NOT reach through the steering wheel to start the engine - reach AROUND the steering wheel; if the valve isn't balanced, you can get a nasty surprise.

[Timothy B.]

Re: C3 Power steering control valve replacement

I'm going to replace the power steering control valve assembly. The one on the car is beginning to leak at the ball stud seal. I just bought a new, not rebuilt unit. Any tips or advice for this job?
Gary

Gary,

Did you send the old valve in for core? If not, I may be interested in it to try and rebuild it myself.

[Gary V.]

Re: C3 Power steering control valve replacement

Hi Tim,
I haven't taken it off the car yet. I'm waiting to get the new one shipped to me. The old one works fine except the small drip from the top ball valve seal.
Gary

[Richard M.]

Re: C3 Power steering control valve replacement

Gary -

When you get to the point where the valve is re-installed and you're ready to bleed the system and balance the valve, DO NOT reach through the steering wheel to start the engine - reach AROUND the steering wheel; if the valve isn't balanced, you can get a nasty surprise.

This is great advice. A friend recently rebuilt his valve on his 77, and on startup he almost lost a few fingers when the steering wheel locked hard to one side due to imbalance in the valve.

Many years ago, after full restoration including rebuilding the R&P PS on the wife's '72 E-Type, I went to move the car out under power. All was fine until I went to turn the wheel. It locked hard and almost took a wrist off. Scared the heck out of me & lesson learned. However, in this case, I had followed the Parts Book diagram on reassembly(no AIM on the old Jags), which inevitably showed the fluid pipes reversed between the valve and the cylinder in the diagram. I found out after a long drawn out diagnosis and finally saw the correct orientation on another rack.

Rich

[Gary V.]

Re: C3 Power steering control valve replacement

Thank you for the advice about the steering wheel. I will disconnect the cylinder rod from the frame mount and balance the valve with the cylinder rod hanging. This should be a lot safer.

Gary

[Patrick H.]

Re: C3 Power steering control valve replacement

Thank you for the advice about the steering wheel. I will disconnect the cylinder rod from the frame mount and balance the valve with the cylinder rod hanging. This should be a lot safer.

Gary

If you buy a rebuilt valve, odds are it will be prebalanced. I have never had to touch the balance on a rebuilt one, and I've installed several.

[Rich C.]

Re: C3 Power steering control valve replacement

I could be wrong, but if memory serves the grease fitting should NOT be greased.

1973 LS-4 454 coupe owned 24 years
1996 LT-4 CE coupe
Victory Hop Devil Ale-currently on tap

[Mike T.]

Re: C3 Power steering control valve replacement

As long as the grease seal is intact and everything is fresh, you probably don't have to worry about it but if the age of the valve is unknown, a couple shots with the grease gun couldn't hurt either. I just finished rebuilding the PS control valve for my 65 Coupe and lathered enough grease in and around the ball-stud and sliding sleeve/ball-cups that I doubt it'll need to be greased for a long time, since I don't seem to put that many miles on my cars.

[Gary V.]

Re: C3 Power steering control valve replacement

I bet if you put too much grease in you could blow a seal.
Gary

[Mike T.]

Re: C3 Power steering control valve replacement

Gary - That's not very likely. Check out this pic of the 'back half' of one of my core PS control valves. You can see the zerk fitting underneath and it feeds the chamber with the sliding sleeve and the two ball-cups that the ball-stud fits into. If you got a bit carried away and gave it too much grease, the excess grease would just try to ooze out that large hole in the casting that allows the ball stud to move freely. The rubber boot/seal that covers that hole and the ball stud is not in place but the replacement boots have a slit in them to allow excess grease to exit.

[Gary V.]

Re: C3 Power steering control valve replacement

Thanks Mike,
All good information to know.

Gary