Steering: Weird power steering lockup -- Avanti

[tluz]

Gentlemen,

OK, now I have a smooth-running Avanti engine as of this morning. It took a few cranks and a primed carb but once she fired she never went back. Powerful ignition and a smooth idle. Lord, it's a beautiful sound. I'll try to record it and post a .wav file.

Then the next weirdness took over.

The steering has locked up.

When I ran the car this morning in the garage, I moved the steering wheel while revving the engine. The wheel immediately started swinging back and forth, right to left, with no input from me. I figure the travel was more than half a turn in each direction. The pump or maybe the pump belt squeaked, not screaming but noticeably. I got control of the wheel and could feel pressure alternating left and right. After a few seconds the spasming in the wheel stopped. I turned off the car.

This afternoon I decided to investigate and move the car. She fired up instantly. When I turned the wheel to get out of the garage something metallic clicked under the car and the steering locked completely. I removed paint and gelcoat from rear quarter panel because the car steered itself against the side of the door. I was able to reverse back in but the damage has been done.

With the engine off I can turn the wheel left and the steering linkage moves left. Going in the opposite direction, I cannot move the steering past straight ahead. It feels as if there is a physical obstruction preventing a right turn. I have jacked up the front end so the tires are off the ground and physically moved the tires. Good to the left, not past straight to the right.

With the engine on, a touch of the steering wheel causes the tires to point about 10 degrees to the right (where I can't go with the engine off) but it locks there and will not turn left or right. Turn the engine off and i can again make a smooth left turn.

There is fluid in the reservoir. The valve was rebuilt by Jon Myer a month ago. no leaks in the ram. I could not find any physical obstruction in the linkage (I was originally thinking a nut or something). There is a slight leak at the bottom of the reservoir.

Up until today the steering has operated freely in both directions with no indication of a problem.

For some reason, this condition is not discussed in the shop manual or in any other publication I've seen. It does not seem to have come up on the forum before either. That said, i figure some of you guys have some thoughts.

Thanks as always,

Tom

[StudeRich]

Someone did report this condition here before, and I am trying hard to remember exactly what the problem was.
The turning left and right auto turn situation I mean.

I am not sure if it was the left and right turn hoses crossed or the adjustment on the control valve or neither!

Maybe that person might chime in, sorry I can not remember this from a year or two ago.

[11SecAvanti]

Check the clearance on the center bell crank where the tie rod ends meet. Is it hitting the oil pan???? Also check the front section where the ram cylinder tie rod attaches? Is the end striking the radiator or anything? Check the steering reach rod. Is it hitting the exhaust or hitting something in the semi moon arch sweep? It also passes close to the left motor mounting plate. And check the 4 hoses installed into the power assembly to make sure they are in the proper threaded holes. Hope you find the problem.

[bezhawk]

The violent surgeing back and fort is the classic symptom of the left and right hoses switched at the power ram. Also take the end cap off the power control valve and check the adjustment nut and the spring under it. It may have been left inadvertently loose. Tighten the end nut untill it bottoms, then back it off a little LESS than 1/4 turn.

[Studebakercenteroforegon]

I agree...left and right turn hoses switched at ram connection.

[tluz]

OK, sounds like it should be a fixable problem. Thanks for the input. I will make necessary changes and report back.

[tluz]

Switching the hoses (while messy) worked like a charm on the auto-steer. STP PS fluid seems to have slowed the leak considerably. Now the last task is to find the obstruction keeping the wheel from turning right. I'm going to look externally, but is there any possibility something inside the ram or the valve went wrong?

Many thanks, Guys.

[Mike]

Look at the front surface of the oil pan. The bolts on the tie rod adjustment sleeves can contact the pan when the car is in use; although it looks like there is plenty of room when on jacks. There is no reason not to reverse the tie rods so the adjusters are outboard; out of harm's way.
It's also a good idea to make both tie rods equal in length. Accurate measurments can be made with a yard stick; from the center of grease fittings. Carefully measure the lengths; average them; and adjust. Toe will be the same as it was; but the steering box action should be centered, if the drag link is set to the right length.
Mike M

[64studeavanti]

Switching the hoses (while messy) worked like a charm on the auto-steer. STP PS fluid seems to have slowed the leak considerably. Now the last task is to find the obstruction keeping the wheel from turning right. I'm going to look externally, but is there any possibility something inside the ram or the valve went wrong?

Many thanks, Guys.

Part of your leak problem may be using Power Steering Fluid. These systems were designed for Auto Transmission Fluid. I believe the current thoughts are to use Dexron. My leaks were so much better after using the ATF.

[tluz]

actually, it was leaking when I used ATF and the leaks stopped with the STP. There are a couple of threads in the Forum archives about this and several guys recommended it, which is why I switched.

Anyway, I could find no visible physical obstruction preventing a right turn. Nothing is hitting the oil pan and the bellcrank arm seems to be free. The reach rods and tie rods aren't close to anything solid at the point where the steering binds.

My next thought is to disconnect the ram ball joint from the bellcrank and see if I can turn the wheels manually. if they move I know the problem is farther up the line. If not, then I missed something. While the ram is disconnected I'll also test the steering wheel to see if it moves past the midpoint with no load on it.

My main concern is that something might have broken in the steering box. I'll try to test things systematically up the linkage and hope it's something simple. Having to remove the steering gear would truly suck.

Any other tests I should try?

[Corvanti]

i'd look at the power control valve. i can't say about the Avanti, but i had a similar problem with my '80 Corvette. chunks of old rubber gaskets in the cylinder... a rebuild kit solved the problem.

i'm going on memory here - on the Corvette, it appeared like a small shock absorber that hooked up with the pittman arm and drivers side steering...

hope this helps. if wrong, someone please correct!

[tluz]

So I disconnected the reach rod and ram from the bellcrank. wheels pivot freely in both directions. Steering wheel is still jammed. The next step is to disconnect the pitman arm and see whether the jam is in the steering gear or the hydraulic system. I'll keep you posted.

[bezhawk]

Check your rag joint steering coupling at the base of the column.

[JoeHall]

actually, it was leaking when I used ATF and the leaks stopped with the STP. There are a couple of threads in the Forum archives about this and several guys recommended it, which is why I switched.

Anyway, I could find no visible physical obstruction preventing a right turn. Nothing is hitting the oil pan and the bellcrank arm seems to be free. The reach rods and tie rods aren't close to anything solid at the point where the steering binds.

My next thought is to disconnect the ram ball joint from the bellcrank and see if I can turn the wheels manually. if they move I know the problem is farther up the line. If not, then I missed something. While the ram is disconnected I'll also test the steering wheel to see if it moves past the midpoint with no load on it.

My main concern is that something might have broken in the steering box. I'll try to test things systematically up the linkage and hope it's something simple. Having to remove the steering gear would truly suck.

Any other tests I should try?

I agree 100% about STP PS fluid. I've been using it in all my Studes, (at least half dozen) for about 15 years now, and its the greatest thing since sliced bread. It slows down seeps/leaks (inherent with just about all Stude PS), and results in a smoother steer feel. I use it in Saginaw & Bendix systems, and have not experienced ANY negative results.

Toss the ATF

[tluz]

I disconnected the pitman arm, isolating the steering gear. I learned that the gear was locked because it had reached the end of its leftward travel. Somehow, when the reversed hoses caused the autosteering and the system became spastic, something slipped internally and misaligned the gear.

Anyway, I centered the wheel, centered the pitman arm, centered the tires, and reconnected everything. Steering now works perfectly. not sure if there is any lasting damage. On to the next issue, in the next post.