Hi All,

I'm a new owner and member to the forum. I've been a fan of the site for some time, but never posted.

I recently purchased a 1970 - the vehicle was upfitted with a power steering system in the late 1990's that doesn't seem to be functioning. I've bled the system a few times, with no change. Here are a few other clues:

- I adjusted the steering valve with the piston disconnected and the wheels off the ground. The piston does move, when I turn the adjuster, which suggests there is some flow/function to the system

- There are no leaks in the system

- With the engine running, the fluid level in the pump does not change when turning lock to lock. The fluid level does change when the wheels are turned with the engine off.


My first thought is that there is an issue with the pump, but the pump doesn't really make noise or anything to suggest that it was failing at any point in time.

Before I go about changing out the pump, I was wondering if there is some sort of pressure valve in the pump that could be stuck/fixed with a fluid flush.

In tandem I was thinking about ordering a pump so I didn't take my vehicle out of commission in case the flush didn't work.

Thanks for your support! And glad to be part of the group.

 

I am trying to answer your question(s) but I do not see that you asked a question. This seems to me you making statements.

YES..inside the pump...behind the large hex nut fitting that your PRESSURE hose attaches to on the backside of the pump is spring and valve inside when you take this large fitting out....but not knowing what is wrong....I can not say much more than that.

DUB

 

Sorry if my statements were vague. I appreciate the response!

I am currently getting no power steering assist at any speed. I have been trying a number of things (short of replacing parts) to diagnose which component(s) could be causing the issue. I am looking for advice on additional trials (or maybe some suggestions on what could be wrong). So far, I've adjusted the valve - that was able to move the piston, which I assume means both the piston and the valve are functioning to some extent.

Tonight, I drained the system - the fluid was nearly black. So whatever is wrong, it's been going on for a while. I disassembled the pump valve and cleaned the components. I had also read a thread about increasing pump pressure, so while I had the pump valve out, I removed one of the small shims. I put everything back together and flushed the system with GM steering fluid - I'd guess I flushed an additional 16oz or so through the system prior to buttoning everything back up. I then filled the system, bled it, and still do not have assist.

I'd appreciate any advice on what to do next. Pump replace? Valve replace? piston replace? Any or all of these could be wrong I suppose, but I'm hoping not!

Thanks in advance!

 

Assuming that your power steering belt is not slipping..and you have no kinks in your hoses.. I would have to start with a pump. With the fluid being black...I wonder if the pump is wiped out internally and can not build pressure...regardless of what modifications were made to it

I would NOT think that your control valve or cylinder need to be replaced.

QUESTION: I feel that you read and have done your 'homework' and when you were adjusting the control valve to get it BALANCED...when the engine is running and the piston shaft of the cylinder is DETACHED from the brackets...the piston should NOT move when the engine is idling. Did yours do that???

Keep in mind that does not seriously effect the fact that oyu have no power assist...but I am just asking.

DUB

 

Thanks for the reply. I did order a new pump....I'll give that a whirl next.

When I disconnected the piston from the frame, it remained retracted, so I turned it until it started moving, then turned it back half way. It was stopped at that point, but the car was on and idling. That was my clue that the valve was functioning. I assume the piston is working because a failure would lead to a leak (fluid bypassing the piston ram).

Could the seals of the valve (not the pump valve) be leaking internally and cause a loss of assist?

 

There are no kinks in the hoses and I didn't see the belt slipping either.

 

I guess anything may be possible...but honestly..I must have replaced so many power steering parts over the years that IF I have a power steering system that does not have good pressure..I go right to the pump....or the valve in the pump.

I have never run into the power steering cylinder that had a bad seal on the shaft. Not saying that it could not happen.

And as for the control valves..I have replaced so many that were leaking that I lost count and I honestly do not know IF it can be your problem...due to what I wrote a moment ago. I feel it is in the pump...ESPECIALLY after what you wrote about the color and condition of the fluid.

DUB

 

Update: I swapped the pump and I have power steering again! Thanks for the tips. The old pump had some pretty nasty stuff in it so I'm guessing the vanes got destroyed at some point.