I have replaced the entire steering setup on my '69 fastback while doing my 383 project. The old Bendix power assist steering system was pretty worn out, so I decided to scrap the whole thing and start new, but stay orginal instead of converting to R&P. Once I got everything installed and chased down a bad PS valve, everything started working. My problem is when I get on a rutted road doing 50+ the car wants to dart around some. There is some play in the steering which accounts for the darting. When on a turn and I have the slack out, the steering feels good and the car handles very well. My question is what should I look at to get the slack and wander out? I thought it was the steering box, orginally, so I put in a Flaming Riverwhen doing to rest of the steering. It guess it could be bump steer, but that does not explain the slack. It apprears that when you turn the wheel, the column turns normally, the pitman arm turns normally, but the brand new PS valve moves some before the steering arm moves. In other words, the PS valve has slack in it. I made sure everything has good grease in it, so that is not an issue. How can I get that slack out of the PS valve?

FYI, I have redone the rear suspension with a 4.5 leaf, tranction bars, and subframe connectors, but have not done the front suspension yet. The car has Granada front disc brakes. Also, the wander is MUCH worst on uneven county roads. On the interstate, it is hardly noticable, but the slack in the steering is still there.

 

I forgot to mention my allignment specs

Camber is 0
Toe in is 1/16"
Caster is 1.5

We could not get anymore caster than that on one side with putting in shims, so evened up both sides. I know 2-3.5 caster would be nice, but that may have to wait until I upgrade the suspension. I am looking at TCP Coil Spring tube lower and upper control arms with the Shelby drop built in.

 

Anyone?

 

Add more toe. My 65 started getting darty and took it to the shop and my 1/8 toe has magically worked its way out to almost 0. Set it back to 1/8 and the dartyness went away. I personally would also go with some - camber...but that's just me.

 

Shims where?

Something is wrong. You should be able to get more caster.

Were you working on the alignment while the car was on the rack or did you drop it off?

IMO, your alignment specs are probably the major contributor to your wandering problem.

-1/8 total toe
-0.5 to -1.0 camber
+3 (or more) caster

.... should get rid of your problem and make the car handle oh so much better.

Dave

 

On my car I would run about -1.5 camber or -2. Caster at 3-4 will get rid of your wander, and a little more toe in will help stay straight. I am actually taking my ASE a4 certification (Suspension & Steering) tommorow so I thought I could help a little bit.

 

-2 camber on a street car is a little on the high side of the norm, but it all depends on the car and how you want it to handle.

Dave

 

I mis-spoke. We did not add shims but rather simply adjusted the strut arms. The most caster we could get on one side was 1.5 and 3 on the other so we evened it up. I guess we could add shims and work on getting the caster closer to 4. That will help with the darting, but so does running my tires at 28lbs vs. 30lbs. How can I get the slop out of the PS Valve so that I have a little more control?

 

If the control valve is rebuilt to perfect operating parameters, I'm not so sure that the "slop/slack" will disappear. We're talking about 40-50 year old technology here... it's only going to get so good. IMO, You're not going to get "state of the art" responsive steering out of the original system. It can be built to be "okay" or "good", but "great"? I don't believe so. This being one of the major reasons why people swap over to a more modern R&P system.

Dave

 

As Dave said, there is very little play in a properly built and adjusted control valve/ball stud assembly.

If the engine is off, and the hydraulics aren't working, sure, there is a bunch of play. But with the system on, the ball stud should move very little before the hydraulics start to move the linkage. If your valve does not work this way, then something is wrong with it.

If it is a new reproduction control valve, that may be your problem, particularly if it is a Flaming River unit.