...sudden shimmy...

[coley]

My son and I were enroute to the store today in the 76 when we hit a big bump and the front end began to shimmy uncontrollably...wheel weight?I just changed the front wheel bearings...readjust?Idler arm?The ride of the car was very bumpy all the way home...we drove VERY slowly...thanks!

 

[wishuwerehere82]

Coley,

Check your wheel bearings again, sometimes they take a good shock to seat the bearing races all the way. While you have it up in the air, spin the tires and check for a broken belt. Put a block next to the tire and use a lever to raise the tire and check for play in the ball joints. A lost wheel weight wouldn't cause that bad a shimmy unless you were going pretty fast. You may have bent a tie rod or lower control arm rod.

 

[coley]

thanks...I'll look at that stuff this morning.

 

[coley]

Well,the front wheels seemed to be really loose...I reset the wheel bearings and it seemed to fix it...thanks!

 

[wishuwerehere82]

That's great!

I'm glad it wasn't anything more serious than that.

Happy trails!

 

[coley]

I changed the control valve and the ram(cylinder)and rotated the tires...it REALLY helped the whole situation...I think I need some smaller tires tho-I can hardly turn the steering wheel sitting still...

 

[wishuwerehere82]

How big are the tires? You may want to change out the power steering pump as long as you did all the rest.

 

[coley]

The tires are 235s,IIRC...I'm going to try tightening the belt...anybody have a spec on that?I don't think the pump is bad...and it looks like a PITA to change out.

 

[wishuwerehere82]

Yes is is a PITA, Aim for 1/2" maximum deflection on the belt when tightened.

 

[coley]

Let me ask y'all something else...due to lack of time,I actually had a shop here in town change the control valve...now the steering wheel isn't centered and it is BUGGING ME!What do I need to do to fix this?

 

[wishuwerehere82]

The Valve isn't bottomed out all the way on the steering relay rod. I'm surprised they could get the retaining bolt back in like that. Check their work out, The steering valve should not have any threads exposed on the rod and should be all the way against the shoulder of the rod end.

 

[coley]

Is this something I can fix easily?...man I get tired of hiring people to fix stuff and then having to fix what they've done-plus I don't have time to run it back and forth to the shop...

 

[coley]

Just went down and looked...there is one thread showing...will the hoses have to be unhooked,system bled again,etc.?If so I think I'll just take it back and let them do it...yes?

 

[wishuwerehere82]

All the hoses have to come off. Bleed it can be done by turning it lock to lock a few times. I would have them explain why it isn't on all the way, they may have had problems getting it threaded. This can happen with rebuilt units because they have too much paint on them. The only other option is the change the adjustment on the tie rods to center the wheel. But I would make them put it on the right way.

 

[coley]

Soon as I finish this cup of coffee the car is going back...

 

[JohnZ]

Let me ask y'all something else...due to lack of time,I actually had a shop here in town change the control valve...now the steering wheel isn't centered and it is BUGGING ME!What do I need to do to fix this?

There's a fair amount of tolerance between the different control valve castings (GM original vs. GM Service vs. aftermarket), and it doesn't take much to affect steering wheel centering; re-setting toe and steering wheel centering is a normal part of control valve replacement. Get it on an alignment rack and have that done (by adjusting the tie rods, NOT by re-indexing the steering wheel on the shaft, which is Bubba's favorite fix).

 

[wishuwerehere82]

Let's wait to see what happened at the shop today.

I agree that there is a lot of variation in the valves that might require a front end alignment to fix. That Valve should be all the way to the shoulder of the relay rod though, do you agree?

 

[coley]

Well...I ran it down to the shop this morning and the mech(who I've dealt with for 20+years)assured me that the control valve was bottomed out...he took great care to make sure the threads were okay on the relay rod and"that is absolutely far as it would go"...when I get new tires I'm to bring it in for a front-end alignment and the steering wheel will be straight.I have no reason to doubt this guy and every reason to trust him.No,I'm not going to take the steering wheel off to straighten it...

 

[JohnZ]

Let's wait to see what happened at the shop today.

I agree that there is a lot of variation in the valves that might require a front end alignment to fix. That Valve should be all the way to the shoulder of the relay rod though, do you agree?

Yes, that's normally the case; the last time I replaced mine, it left about 1/16" from the end of the valve to the shoulder on the relay rod. The valve has to be properly oriented radially, and that gap will vary based on how the threads were machined. I run them down until they bottom out, then back off from there to the correct radial location (the clamp bolt won't install unless the valve is properly oriented, as there's a "notch" machined across the threads for the bolt).

 

[coley]

Yeah,the guy said the bolt went in just like it was supposed to...