No Power Steering Assist At Idle

[Charlie Brown]

Although this pertains to my 1962 300, I thought I'd put this out to you guys. The power steering works fine at speed, but at idle I have very little or close to no assist. I rebuilt a TRW pump previously because it was leaking, and it worked fine. About 1000 miles after rebuild, the no assist started. Last week I rebuilt a second (different) pump - same results - no idle assist. The steering box has about 30k on a Firm Feel stage 2 rebuild. The no assist thing happened quite suddenly. Appreciate any input.

 

[66 Sat]

Do you maybe have the same "little assistance" at speed too, but you don't notice because the car is moving and the steering is naturally lighter?
What happens if you increase the revs when stationary and move the wheel? Do you get normal assistance?

 

[kiwigtx]

Although this pertains to my 1962 300, I thought I'd put this out to you guys. The power steering works fine at speed, but at idle I have very little or close to no assist. I rebuilt a TRW pump previously because it was leaking, and it worked fine. About 1000 miles after rebuild, the no assist started. Last week I rebuilt a second (different) pump - same results - no idle assist. The steering box has about 30k on a Firm Feel stage 2 rebuild. The no assist thing happened quite suddenly. Appreciate any input.

Is the fluid level correct?

Is the belt tightened correctly?

Steering should get progressively lighter going up in engine RPM's..... if not, the pump is not working correctly.....or there is a blockage in the system somewhere.

 

[1967coronet]

Check your pump bracket, Some of the early 60s ones are self adjusting bracket.
You may need a new belt if you have that style.

 

[Charlie Brown]

Do you maybe have the same "little assistance" at speed too, but you don't notice because the car is moving and the steering is naturally lighter?
What happens if you increase the revs when stationary and move the wheel? Do you get normal assistance?

Increasing the revs while stationary, results in "normal" steering effort.

 

[Charlie Brown]

Check your pump bracket, Some of the early 60s ones are self adjusting bracket.
You may need a new belt if you have that style.

All that is good and tight - no belt slippage.

 

[1967coronet]

Many of the older federal and trw pumps have a filter screen in the return line tube on the pump.
It's possible it may need cleaned.
Most of those pumps hold up great as long as they are not ran dry.
But I guess it is possible the pump is getting tired.
Check for a screen though.

 

[Charlie Brown]

Many of the older federal and trw pumps have a filter screen in the return line tube on the pump.
It's possible it may need cleaned.
Most of those pumps hold up great as long as they are not ran dry.
But I guess it is possible the pump is getting tired.
Check for a screen though.

Hi, Just did a complete rebuild on this pump and the screen is clean. This is the second pump I have rebuilt with the same results.

 

[1967coronet]

Hi, Just did a complete rebuild on this pump and the screen is clean. This is the second pump I have rebuilt with the same results.

I have to ask are you sure you have all the air bled out of he system ?
With the cap off at idle are you seeing a good return flow ?
Are the hoses new ? Could have a pressure hose collapsing or chunks of return hose in the sector ?
Possible worn parts in both those pumps.
When you said rebuild, was it just seals ?

 

[Charlie Brown]

I have to ask are you sure you have all the air bled out of he system ?
With the cap off at idle are you seeing a good return flow ?
Are the hoses new ? Could have a pressure hose collapsing or chunks of return hose in the sector ?
Possible worn parts in both those pumps.
When you said rebuild, was it just seals ?

Ok, so I checked the hoses while running - seem good. Checked flow in pump - hard to see, but I do see flow. In regards to bleeding - I jacked car up and while not running, cycled steering gear about 20 times, then while still having the front wheels off the ground, started the car and cycled the steering gear an additional 20 times. During the most recent pump rebuild, I replaced all the seals, gaskets and shaft bearings. After lowering car, the results have not changed - barely any assist.

 

[eldubb440]

is an undersize pulley available?

 

[Charlie Brown]

is an undersize pulley available?

Maybe, but I've been driving this car for 15 years, with over 30k on her and this is a recent issue. I'd like to diagnose the underlying issue.

 

[Charlie Brown]

Well, found the problem. It was the pump(s) all along. I had several old pumps lying around and put one on and all is well. Thanks to all who responded.

 

[kiwigtx]

Well, found the problem. It was the pump(s) all along. I had several old pumps lying around and put one on and all is well. Thanks to all who responded.

So your rebuild work didn't improve the steering box?

 

[Charlie Brown]

So your rebuild work didn't improve the steering box?

The box is fine. It's the pumps that were no good. What are the odds that both rebuilt pumps were toast - or I messed up the rebuilds.