I recently replaced the ps pump, control valve, and cylinder along with new ps hoses. The ps works fine while steering the car once the car gets going, however the ps developes a puslation while turning from a very slow or stopped position.

Could it be an aeration problem?

 

Could be air, or the adjustment nut on the end of the control valve might not be adjusted correctly. I'd drive it around for awhile before I tried to adjust anything though.

 

Thanks for the reply, torqvette. The adjustment nut on the end of the control valve is a centering adjustment to keep the car going straight. Since the car tracks very straight while in motion; I don't think I want to touch that right now.

 

If you failed to try and deaireate the power steering system before starting your engine, you most likely whipped air that was in the system with the oil and now you will have a compressible fluid for a short while.

I would give your system a day or two to see if the system calms down and acts correctly. Just sitting overnight should allow most of the air to work its way up and into the reservoir where it can escape to atmosphere.

Jim

 

Thanks for the reply Jim. I thought I followed the instructions that came with the ps pump, control valve and cylinder. Maybe there is still air in the system. How would you have deairated the system before starting the engine? Do you think purging the system would help? or just leave it?

 

I got a note from the ps parts re-manfacturer saying that it sounds like either a sticking flow valve or air. They said to try removing the pressure side nut fitting, pull out the flow valve & polish the surface w/ fine emery cloth. Wash it off, reinstall it & make sure it moves in & out freely. If that doesn't work try to vacuum bleed the system.

 

When your rotate your steering wheel full lock to full lock without the engine running, you are mechanically pushing the oil through the various parts of the system. This causes big air bubbles to move around until they get to the reservoir where the come to the surface and go to atmosphere. As the big bubbles come to the surface, the level of the fluid in the reservoir will drop.

If you start the engine and whip the air/oil to a froth, the apparent fluid level will rise because foamy air/oil takes up more volume than plain oil.

I would give your oil a day or two to work the air out of the system. I wouldn't screw around with the flow control valve yet.

If you finally decide to check the flow control valve, first try and siphon as much oil out of the reservoir as you can. Then you remove the power steering hose from the back of the pump. Now unscrew the fitting that the hose was attached to. Behind the fitting (inside the pump) there is a sliding valve. There is a spring behind it trying to push the valve toward you. Use a thin screwdriver or punch to depress the valve into the pump bore. It should slide easily back and forth in the bore. If it sticks, send the pump back because the pump rebuild company sent you a piece of junk. You shouldn't have to fix their screwups.

Jim

 

Thanks for the reply Jim.

I have not run the car since Saturday. Today when I drove it, the problem is still there, however it appears to be much less than before.

I am going to just leave it alone as per your suggestion and not mess with the flow control valve. My feeling is that since it appears to be getting better, I certainly do not want to open up the system again and run the chance of introducing more air.

Thanks again.

 

Jim,

I followed your exact instructions using a cotter pin to push the valve and the valve does feel like it is sticking. It does not slide back and forth easily. I still have the original pump and the valve in the old pump slides freely. I am going to remove the pump and return it for a refund. Thanks again for your help.