Power steering easy to right hard left

[GT350AUS]

My power steering on my GT500KR was perfect when I parked the car 3 years ago but  now its assisted turning right but turning left it feels like there's no assistance at all.

I rebuilt the control valve 6 months before parking the car up for 3 years and everything was fine.

Now I assumed that air must've gotten in somewhere as a result of a low pressure hose leak. When i try to bleed the system by turning left to right with the wheels off the ground all feels good but its leaking from the low pressure hose.

Putting it back on the ground and its still the same...easy turning right but rock hard turning left.

I've got the carby off for a clean and rebuild so I'll sort the leak out once its back on the car and running.

Other than the leaking low pressure hose, does anyone have any ideas as to what the cause may be??

[greekz]

Maybe a problem in the power steering cylinder not letting the fluid flow freely.  Just a guess.

[TJinSA]

I would suspect the power cylinderhas become stuck in an off center position. The ford system has a natural  sloop in the system where a movement of the steering displaces a sliding valve in the control cylinder opening the pressurized fluid from the pump to work its magic. That sliding valve (piston) must return to center or you have assistance to only one side

[1967 eight barrel]

Spool vavle is stuck.  I know many of us have used him.
Rode's Restoration in Ohio.
1406 Lohr Rd, Galion, OH 44833
Phone: (419) 468-5182

[Dizzy]

There is a plug at control valve that can be removed and a zerk installed to lube the valve.Not too much,just a squirt or two. Worth a try!

[1967 eight barrel]

The zerk isn't for the spool. It lubricates the pitman arm pivot. 

[Dizzy]

Pitman arm pivot? Not even close. The pitman arm is not part of control valve assembly....here is a picture of the valve from Ford shop manual. Note the "lubrication plug" that lubricates the control /spool valve. Just a little grease can free up the valve.

[JWH]

I found this Q&A which may help? The answer comes from Average Joe Restoration:

Car was restored 3 years ago and driven lightly since then. I then purchased it and immediately found out the Power steering was messed up although everything under the front end was all new, nos, oem and or rebuilt to oem.

But the power steering is very quiet and does a great job as long as I am turning to the right. But I have to use both hands as if it were manual steering when turning it to the left. Parking or on the road. I have had it in 6 different shops and spent a ton of money on it and still like it was. It never makes any noises idling and or on road. What can be wrong with it and what do I get done to it to fix it. Last shop said to replace it all, Pump, Ram, drag-link and complete control-valve assembly.??

Answer:

The control Valve: the control valve determines which side of the ram cylinder gets pressurized to retract the rod or extend the rod from the cylinder.

So there are two possible problems: the cylinder may have a bad seal that is allowing the pressurized side fluid to pass to the return side or the control valve is failing and a seal in there is letting pressurized fluid pass or is restricting pressurized fluid from getting to the ram cylinder.

Here is the link:
http://averagejoerestoration.com/how-mustang-power-steering-works/

Jeff

[GT350AUS]

If the spool valve is in fact stuck is there any way of freeing without pulling it apart as I had rebuilt the valve 6 months before parking it for 3 years

if tried turning the steering from left to right repeatedly with no luck.

Just trying to avoid pulling it all apart again.

[67350#1242]

The problem could also be attributed to the spool centering spring adjustment, (under the aluminum cap) or to a weak centering spring.   If this is the cause you may also notice the car will want to pull to one side while driving.  The adjustment is made to achieve equal steering effort left or right, as it places the spool in the center of the valve at rest - equal pressure to both sides of the ram.
Kurt.

[GT350AUS]

Kurt, thanks for your suggestion.

I don't think it will be the spring adjustment or spring itself as it's a new spring and the adjustment was set to the correct tolerance at the time of rebuilding the control valve.

However it's easy enough take off the cap and check so I'll check.

Ross

[67350#1242]

Kurt, thanks for your suggestion.

I don't think it will be the spring adjustment or spring itself as it's a new spring and the adjustment was set to the correct tolerance at the time of rebuilding the control valve.

However it's easy enough take off the cap and check so I'll check.

Ross

Note of caution:  this may be obvious, but don't start the car with the cap removed or you'll have fluid squirting out.

[GT350AUS]

Sometimes what's obvious can be missed but thanks for the word of caution just the same.

Once sorted I will get back on to the forum and let everyone know for future reference.

[1967 eight barrel]

Pitman arm pivot? Not even close. The pitman arm is not part of control valve assembly....here is a picture of the valve from Ford shop manual. Note the "lubrication plug" that lubricates the control /spool valve. Just a little grease can free up the valve.

Obviously you've never rebuilt a Control valve. The spool valve is not greased. It is lubricated by the power steering fluid it controls. The ball stud that goes to the pitman arm is lubricated by that point.
                                                                                              -Keith

[GT350AUS]

If it is a stuck spool valve or possibly even an issue with the reaction valve I'm considering just removing the control valve body and pulling that down.

Does anyone see an issue with doing this and leaving the the ball stud assembly fitted thereby leaving it in place and with the ball stud fitted to the pitman arm?