Power Steering Cont Valve, wheel jerks to the left???

[David M.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Interesting thanks for the reply!

[Charles H.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Dave-
Be sure to check that the tie rod ends are installed into the forward holes on the steering knuckles. The rear holes are for manual steering, and require more turns of the steering wheel to reach the locks. I'm not sure if this will help, but it seems logical, as more movement of the relay rod will cause more push or pull of the steering cylinder.
Just a thought...
Chuck

[Richard M.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Is it possible that the Ball joint on the Pitman arm is egg shaped, and/or the tension of the ball socket housing cups and springs is not tight enough?

Could conditions such as these cause it as the principle of operation inside the valve(s) relies on a tight ball joint to actuate the internal valve operation?

Rich

[David M.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Dave-
Be sure to check that the tie rod ends are installed into the forward holes on the steering knuckles. The rear holes are for manual steering, and require more turns of the steering wheel to reach the locks. I'm not sure if this will help, but it seems logical, as more movement of the relay rod will cause more push or pull of the steering cylinder.
Just a thought...
Chuck

Yes the OEM knuckles still have the lead tamped into the outer (towards the rear) holes.

[David M.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Is it possible that the Ball joint on the Pitman arm is egg shaped, and/or the tension of the ball socket housing cups and springs is not tight enough?

Could conditions such as these cause it as the principle of operation inside the valve(s) relies on a tight ball joint to actuate the internal valve operation?

Rich

Im open to anything. It just was aligned by a guy who has been doing vettes for 40 years. And the only thing thats not new in the front end is the tie rods, center link idler and pitman. But they all appear to be nice and tight. I felt them when everything was apart. The ball and sockets are all nice and tight. The taper in the pitman is good. Didnt pull apart the idler. All these mentioned parts appear to be relatively newer to the car. I will double check for any unwanted movement again. When I manually turn the wheels with the car on the lift I dont see or feel anything bad. Good theory thanks.

[Patrick H.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Im open to anything.

I'd buy a rebuild kit, remove the valve, and open it up. You're not going to break anything at this point, and you may find a fluid passage that's narrowed or a bunch of gunk inside. Clean it internally as much as possible, and reassemble.

Other than the cost of the kit and some time, you have nothing to lose.

[David M.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Good thought. Of course I sent the original back as they give you 50 bux back even though the new valves dont have a core charge. I would love to have that OEM valve apart on the table to compare to the new ones internals. 3 new(not remans) valves in a row purchased from Ecklers. All three do the same thing. Its either bad luck or something else is the root cause. Then each time I put the new valve on I have to get it realigned for 100 bux. I really dont want to take anything apart until I have some answers from the manufacturer. Ecklers is in Florida. So Im waiting a bit for them to recover before I start making the phone calls. I want to discuss this with the company Ecklers purchases these units from.

[Patrick H.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Why do you have to have the car realigned? I've replaced several of these and never realigned the car. You're not touching the alignment whatsoever when you remove and reinstall the valve.

Oh, and you've now apparently learned one of the other rules of Corvettes - NEVER turn in an original part. Consider the core charge to be part of the overall cost of the repair.

[David M.]

Re: Power Steering Cont Valve, wheel jerks to the left???

The steering wheel was off. You can be off one turn in either direction when screwing the valve onto the center link and the bolt will slide through the half moon shaped milled out locator. I didnt have time to monkey with it so we just had the guru re do the realignment. I really didnt want to disassemble it again. Chances are Id damage that saddle and didn't want to go there...path of least...to get it on the road for the end of the cruse season.

[David M.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Reviving an older thread as we have not fixed the problem yet. Steering wheel will still hydraulically lock if turned CCW full lock. Have to stop the engine to release it. The ram is over centering.

The new valve is balanced as per the spec. Went through 3 valves to find one right. We striped the front end down to the frame and rebuilt it with Corvette Central parts, New A arms et al.

Everything was replaced up front in 2017. Its exhibited this problem since.

I did notice the right to left inner/outer/ tie rod assemble are not even, one side is longer. The driver side tire rubs on the inner side of the frame. Running 225 size tires.

So its with our local corvette experts now for an alignment & to troubleshoot the lock up problem.
They put it on the lift and noticed the left knuckle stop has less material then the right. Ordered a referb from Zip its not much better.

We feel the left hand knuckle hard stop where it contacts the A arm is wrong. Not enough material on the hard stop.

See the difference from left to right as far as more material to make contact with the lower control arm.

Could the tie rod imbalance be the root cause or the lack of hard stop material on the knuckle?

So far everyone's perplexed. But the alignment hasn't happened yet until we verify these 68 knuckles are normally like this. The right has more meat vs the left.

Note the lack of material on the left knuckle stop feature compared to the right

[Gary R.]

Re: Power Steering Cont Valve, wheel jerks to the left???

David
Was the Steering Gear ever serviced to your knowledge? I have seen where the sector was installed off center in boxes, it was extreme but happened and usually would show up right away. These boxes rarely have the true center and high lash in the same position as they should be, that's textbook but in reality, they are often off. It might be interesting to see where the box is setup, assuming your control valve is indeed good, hoses correctly installed, etc.

[David M.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Steering box has never been out. But that doesnt rule it out. The car didnt do this until the front end rebuild. At least we never noticed it. The ram is definitely over centering causing the pump to to pressurize it. At least thats our best root cause guess. The place that has it now only works on vettes. C1s to C8s. They noticed the knuckle not having equal amounts of metal at that hard stop area. The refurb one just received from ZIP is about the same maybe 1/16" more material.
Again the inner/ outer tie rod assemblies are noticeably different in overall length. Maybe evening that out will help. The shop wants to address this lack of material on the knuckle before proceeding with the alignment in case something needs replacement. Im going to call ZIP and have them look at their inventory to sample a few other knuckles to see if they are all the same.

[Joe L.]

Re: Power Steering Cont Valve, wheel jerks to the left???

Reviving an older thread as we have not fixed the problem yet. Steering wheel will still hydraulically lock if turned CCW full lock. Have to stop the engine to release it. The ram is over centering.

The new valve is balanced as per the spec. Went through 3 valves to find one right. We striped the front end down to the frame and rebuilt it with Corvette Central parts, New A arms et al.

Everything was replaced up front in 2017. Its exhibited this problem since.

I did notice the right to left inner/outer/ tie rod assemble are not even, one side is longer. The driver side tire rubs on the inner side of the frame. Running 225 size tires.

So its with our local corvette experts now for an alignment & to troubleshoot the lock up problem.
They put it on the lift and noticed the left knuckle stop has less material then the right. Ordered a referb from Zip its not much better.

We feel the left hand knuckle hard stop where it contacts the A arm is wrong. Not enough material on the hard stop.

See the difference from left to right as far as more material to make contact with the lower control arm.

Could the tie rod imbalance be the root cause or the lack of hard stop material on the knuckle?

So far everyone's perplexed. But the alignment hasn't happened yet until we verify these 68 knuckles are normally like this. The right has more meat vs the left.

Note the lack of material on the left knuckle stop feature compared to the right

David-------


The stop on the left steering arm does look like it's been machined slightly. However and regardless, both stops appear to me to be about the same "length". Even if there were a slight difference, I really don't think that's the root cause of your problem.

What are the forging numbers on each arm?

[David M.]

Re: Power Steering Cont Valve, wheel jerks to the left???

David-------


The stop on the left steering arm does look like it's been machined slightly. However and regardless, both stops appear to me to be about the same "length". Even if there were a slight difference, I really don't think that's the root cause of your problem.

What are the forging numbers on each arm?

Joe Ill have get that info. The car is at the vette dealership.

I did have ZIP pull all of their LH refurbished knuckles off the shelf and compare them to the pictures from the mechanic. He said they look similar. The part we had delivered to the mechanic from ZIP looks the same as well. He said maybe 1/16" more material.

Corvette central is looking at their referbed parts too. They didnt get back to us yet.

TX
Dave

[Timothy B.]

Re: Power Steering Cont Valve, wheel jerks to the left???

David,

IMO, there has got to be something amiss inside the valve leaking fluid into one side of the slave cylinder. Where did these parts come from?