Help! 1967 Power Steering not centering correctly?

Grayle · 09-09-2002

I just got done rebuilding the entire steering system, suspension and converted to disc brakes. My power steering seems to be working fine, but the car seems to wander. After turning the steering wheel turn go aroung a turn it seems like I have to turn the wheel a little the opposite way to get the wheels to center again. Do you think this is an alignment issue or could it be the centering spring on my control valve? Please help!! Thanks, Grayle

Twister · 09-09-2002

did you change the power steering ram? I would also try adjusting the steering gear box

Grayle · 09-09-2002

The steering box is rebuilt and the ram is new not rebuilt. The steering box should already be adjusted.

Jeff65 · 09-10-2002

Sounds like the alignment needs more positive caster. Caster is the property of alignment that brings the wheel back. Not enough gives the result you have (oversteer) and too much leads to understeer. Caster is adjustable on your '67. Its the adjustment on the strut rod that need to be tightened more. The shorter the rod, the more caster you'll have.

Grayle · 09-11-2002

You know I'm thinking the same thing. My brother works at the ford dealer and helped me do the alignment. (It was Free)He asked the best alignment guy in the shop what he thinks my specs should be. The caster adjustment took us the longest because the machine doesn't register it when you do an adjustment. You have to turn the wheels back and forth each time an adjustment is made. I think the spec is 1 degree positive caster on both wheels. He said it should be 1.5 degrees on the left and 2 degrees on the right, so thats where we put it. Maybe I should go with what the shop manual tells me!! I was also considering that since I put in the 1 inch drop 620 coils in, that it changed my suspension geometry and now I have some thing called bumpsteer. I'll write this as a new topic. Maybe some else knows more about this.

Twister · 09-11-2002

you need more caster!!! you lower it, you add more caster

Grayle · 09-11-2002

So if I have it at 1.5 left and 2 right, where should it be to add more caster??

Twister · 09-11-2002

you have different amounts on each side?
take it to a person that knows Mustangs....

Grayle · 09-11-2002

My brother said that the difference in the caster compensates for the angle on roads for the water to run off so your car will go straight!? I'll just bring it back and set it to shop manual specs and see if that doesn't help. Maybe that difference only applies to new cars, not ones that are 35 years old

Twister · 09-11-2002

Grayle, custom suspension should always be set up by a pro that deals with modified cars

Grayle · 09-11-2002

Its not technically modified it just has the shelby coils. I can do the alignment, I came here to get help, but if only professionals do this, then I guess I'll have to go to someone who can help me.(I just hate bring my car to some one else!!)

JUSTNLX · 09-11-2002

I really don't think it is a bump steer problem. I my self like as much caster as you can get. Your brother is correct. If the roads where you are have a heavy crown then you would set about 1/2 deg more caster on the drivers side. If not then don't worry about it

Recheck everything make sure things are greased and tight.

Grayle · 09-11-2002

Justnlx, What do you mean by you like as much caster as you can get? Should I raise mine from 1.5 and 2 to 2.5 and 3?? Would that make things better??

JUSTNLX · 09-12-2002

Well caster does not wear tires. So why not use more.

You lowered your Mustang to handle better. More caster will help with high-speed stability. Plus it helps center the wheel or bring the wheels straight. One draw back, higher effort on the steering wheel.

One more thing. Did you change tires too? Some tires will follow the grooves in the road.