I just replaced a leaking power steering control valve on my 78 350 4 speed. Something is not right. After replacing the valve, I balanced it as instructed. When I went for a test drive the steering is not smooth when turning. It almost seems like it is sticking or slightly jerking when turning. At first I thought it may be air in the lines; but after sitting over night, the same condition still exists. Any thoughts or recommendations?

______________

With the front wheels off the ground, start it up. If steering wheel jerks one way or the other, it's NOT balanced. Be CAREFUL when starting car, DO NOT have your arm through the spokes on the steering wheel. Reach around it to turn the switch. If it jerks, you have to turn the adjustment on the end of the valve to correct it. You only need a small amount to change it. The possibility exists that the valve inside the unit is not assembled correctly.

______________

Click on image for full view

I think you have to run the steering wheel lock to lock a few times to get the air out.

______________

   

Thanks for the input. I will put it on jack stands tomorrow and check the balance. I will let you know the results.

______________

I lifted the front of the car off the ground and started it up. The steering wheel did not move. I turned the wheel all the way to the right with no issue; but when I turned it to the left as I got to the left lock position it made a sharp jerk left and a squeal. This power steering control valve is a replacement for the one I put on about a year and a half ago. The original valve started to leak so I ordered a rebuilt valve through Advanced Auto. After having a great deal of difficulty removing the original valve the instillation of the new valve was easy. Then this past July the new valve started to leak. It was still under warranty, so I ordered the replacement from Advanced Auto again. This time as I was installing it the threaded shaft did not align properly with the pitman arm. When I put the shaft in the whole of the pitman arm, the angle was off and the shaft would go all the way through and seat. Finally I was able to get some threads to come through the pitman arm and was able to pull it into position with the nut. Right now I at a loss as to what to do. My inclination is to take the valve off and have it replaced again. I know this is a lot of info; but any thoughts would be greatly appreciated.

______________

Jim, not sure about the pitan arm alignment issue you described but I have heard about many problems with newer rebuilt control valves coming from China. I would definitely get another valve from your supplier and try again. Follow the balancing procedure with the wheels of the ground and make sure the hoses are installed crossed at the valve. Once balanced, turn the wheel lock to lock a few times as described by Gary to purge any air in the system and top off the PS fluid. After topping off the fluid, I would check the balance one more time (wheels still off the ground) and see what you've got. Hopefully you can get a good valve, good luck and let us know how it goes.

|UPDATED|10/20/2016 11:56:40 AM (AZT)|/UPDATED|


______________
John Sigmund

John, thanks for the advice. That's the route I will take. I will let you know the results.

______________

Removed the power steering control valve today and returned it. Replacement valve due in on Oct 28th. Will keep everyone posted on the results.

______________

Good Morning Pappy, I have a suggestion for your PS problem and it sounds a bit crazy,however works every time I have done the process.Trust me on this. After installing power Valve etc. and you still have it jacked up do not try to turn the wheels as yet.Fill the PS reservoir to the mark designated cold,leave the cap of the reservoir OFF and take the jack stand for the RIGHT side of the Vette,leaving left side up and maybe jack it up a little more. Now with the cap off,reservoir fill to cold on dip stick,take a walk or do something else without disturbing the pump. Wait till next day or 24 hours later,check the level of reservoir and it should be lower than it was when you left it,thereby expelling all the air in the system.  I know it sounds crazy,however I have done this procedure every time I have rebuilt or replace a power steering pump on many different cars.When you initially replace a pump etc. and turn it left to right etc. you introduce air in the system if it has a VAPOR area in the system. Good Luck and I hope this helps..Sal C                     nosal

nosal, thanks for the info. You are right, it does sound crazy; but when you think about it, it makes sense that the air will rise to the highest point. I may try it when I get to that point. I did find a video on YouTube that shows and explains the whole process of replacing the valve. It is done very well.

______________

Pappy, Air bubbles seek a path of least resistance and that is why the cap has to be off. I hope all works out for you.Could you please send me the You Tube video you mentioned to either my PM or my email address.I did mine about 20 years ago and wanted to see if there is a better or newer way of doing..Email is:  nosal1@verizon.net  Thank you,

Project update: The valve arrived today. I took my time installing it and everything seems to be good. I bled the system, balanced the valve and went for a test drive. All is good! I will check the fluid level again to make sure it is ok. I do have one additional question. Does anyone know the torque spec for the power steering cylinder? Thanks to everyone for their impute

______________

Experience [well at least for me] is a great teacher, I had to replace the PS control valve on a '74 I owned a few years back so I went the rebuilt route and couldn't get the darn thing balanced even though it was supposedly balanced when it was rebuilt. After much frustration I finally bought a new one at a lot more money and installed it with no balance problems.

______________

Pappy,

______________

 

 

Steevo, thanks for the info. The car is handling fine (took her for a ride today). Glad yours is working for you.

______________