[steverino]

Yet another question ?
After firing this car last night 66 gto with a 71 455, has 71 style crank pulley, and a 67 style ps pump.
After initial fill, when starting eng, the wheel cranked full to left stop hard on its own.

Shut off, fill fluid, stuck on lh stop.

After air in fluid settled, and level now full, was able to get steering unstuck from the left and turn all the way right ok with eng off

But with eng running, the wheel is shaking/jumping and will still occasionally rip right fom my hands and go to full left stop.....no noise from pump now that fluid is full

these are old parts that came with the car but I was hoping something would work and not need replacement ?

Does this sound like a steering box issue ?

I'd like to drive this car, but not like this !

Thanks

[merlotgoat]

Yes, problem with the steering box. There are valves that regulate pressure one direction or the other that are triggered by pressure caused by turning the wheel one way or the other (rotary valve). The opposing pressures are equal when you are not turning the wheel. When you turn the steering wheel, the valve system creates more pressure on one side of the system creating assist. When you stop turning the wheel, all pressures should equalize, causing no assist. Obviously, when the wheel pulls itself all the way to the left, there's no counter pressure to equalize the system. The shaking wheel could indicate that there is air in the valve system. Try purging the system of air by working the steering wheel back and forth with front wheels off the ground for a period of time.

[steverino]

thanks
this box has been on the frame (waiting) for near 7 yrs, so not surprising if a valve has stuck inside

I just am not sure i'll be able to trust it even if it does free up now.

Air bubbles are pretty well worked out of reservoir, and fluid still up there, no noises from pump. I was able to turn wheel lock to lock while it ran, but it will still take the wheel and drive it to full left unpredictably at times.


I think I am replacing this box before I get further

S

[arbys]

Why not try merlotgoat's suggestion first. Sometimes bringing additional factors, a new steering box, brings in additional factors when the problem may not be completely in the box at all.

[steverino]

Originally Posted by arbys

Why not try merlotgoat's suggestion first. Sometimes bringing additional factors, a new steering box, brings in additional factors when the problem may not be completely in the box at all.

I tend to agree, a "rebuilt" a-1 box could be another variable.

It was downright scary the way that wheel rips though, glad I wasn't driving it

I actually think I have a leftover box from another 66 I had that leaked all the fluid out the lower seal, but otherwise worked well, so I am thinking of trying a seal in that first and installing it.

I was able to get the wheel turning back and forth, so I believe all the air is purged,but it will still stick and when it does, several turns the wheel spins at a high rate....dangerous !

[arbys]

Bob gave a very good description of how the PS system operated. I can see where debris or air in the system could cause some problems and until "flushed" out could make it operate irrational at times.

[Mister Pontiac]

Originally Posted by steverino

I tend to agree, a "rebuilt" a-1 box could be another variable.

It was downright scary the way that wheel rips though, glad I wasn't driving it

I actually think I have a leftover box from another 66 I had that leaked all the fluid out the lower seal, but otherwise worked well, so I am thinking of trying a seal in that first and installing it.

I was able to get the wheel turning back and forth, so I believe all the air is purged,but it will still stick and when it does, several turns the wheel spins at a high rate....dangerous !

Hmmm... Was this rapid turning occurring with the front wheels off the ground, or sitting on the ground? I'm curious if it would do this with weight on the wheels.

And if you decide to reseal your old box, remember that there is an entire 'stack' of seals and backup plates down along the output shaft towards the pitman arm. You'll likely need to to pull the box, and blow some air psi into it to get the whole stack loose. It's rather easy with the box off the car, and a $20-$30 seal kit on hand. Oh, and an exploded diagram is very helpful when reassembling. Check your service manual...

Hope that helps, and good luck!

[steverino]

Wheels were on the ground.
I may try it once more after disconnecting pitman arm but before removing the box.
I am planning to just do the lower seal, I was able to get a kit for it.
Just hope I can find that old leaking box upstairs !
I know the weight could have some affect, but I have never experienced anything like this ! And I've seen lots of strange power steering/ air issues (worked in garage at a ford/Lincoln/mercury dealer for years)

[steverino]

I did try ti again this am with wheels off ground. Result was not as fast and far a turn, but it still turns on it's own.....something must be jammed in those valves
I found my spare box and am going to put a lower seal in it and try to use it. I may keep it in there as it is 3.5 turns vs 4 turns for the one in the car currently

thanks

[arbys]

Be sure to keep us posted as to what you find.

[steverino]

Yes, as suspected the steering box was the culprit.

I replaced the lower shaft seal in the 3.5 turn box I had saved from the last car...
Installed, ran 2 qts of fluid cycling the engine and steering wheel until clear fluid was coming from return hose of box, then lowered, cycled, bled air out all without issue. was able to take for a short ride (finally!) last night.

I may take this box apart to see inside. I probly will never use it as it is a 4 turn box anyway, but the cores are not cheap !

I did notice as soon as it the pitman arm was disconnected from the center link, this box seems to have no preload on the input shaft whatsoever. Perhaps adjustment or rebuilding could save this 4 turn box, but I have other issues to shakedown currently anyway, so we'll run the box that's in it for now

thanks for the tips guys !
S