Power Steering Pump Issues-UPDATE 6/11

I have a 1969 Mercury Cougar XR7 390 Auto with air. Since acquiring this car, I have replaced the power steering pump 4 times. Originally, it was replaced because the original was leaking and the new pumps ended up leaking at some point soon after replacement.
Since the orgininal, I have not been able to have “quiet” steering. It’s always whining. For a change this time with the 4th pump, I have no leak, but still have the noise.
All the other power steering related items like hoses, control valve and ram cylinder have been replaced.
Any thoughts?
Thank you,

When you replaced everything did you bleed the system real good? Air in the system will cause noise just like being low on fluid. Might also make it steer hard.

There was a neat method, given by BillB, maybe on MCN, but it’s not searching too well at this time. It beat the turkey baster method by a lenght…

Thank you for the response.
It wasn’t bled very well other than cutting the wheels back and forth. The steering does get a little tight when cutting the wheel fully to either side. I will try your suggestion.

Thank you for the response.
Is that mercurycougar.net?

I have ran through power steering pumps in my 2 70 cougars. I have the 351 C and have used Carquest remanufactured pumps. They make noise and leak. The one thing that I have used to quieted down the pump on one car and stopped it from leaking out of the back fitting is LUCAS power steering treatment. It’s expensive but I haven’t changed a pump on it since. SalD

A couple of suggestions. Before installing the pump put a plug over the return fitting and fill it with fluid. Next prime the pump by turning it over by hand until fluid starts to squirt out of the pressure fitting. Make sure the pump keeps full with fluid while priming it. Cap off the pressure port. Now install it in the car. When installing the hoses try not to loose too much fluid (yes it is messy). Once it’s installed check the fluid level. Now lift both front wheels off the ground. Start the car and shut it off after a couple seconds. Check the fluid level and for any leaks. Start and run for 15 seconds and stop it again. Check the level and for leaks again. Now start the car and begin moving the steering wheel left and right about 1/8 of a turn in either direction. Shut off the car and check the fluid and for leaks. Now start it again and turn slowing 1/4 turn each way, then 1/2 turn each way and finally full turns left and right. Stop car and check fluid.

All this helps eliminate air getting into the system at the beginning and causing the whine. After you’ve done all the above let the car down and go for a test ride.

Good luck.

yes, but i could only find a 4 week history. The whole site seems to be going down the tubes.

What Bill was showing me is how to change the power steering fluid for the proper one. Some idiot (thatwouldbeme) put the wrong stuff in there while on a trip.

I figure that if you change the fluid, it should do a good job of insuring there is no more air in there… since it was a real great method.

unplugging the lines, pouring the new stuff in, pumping the bad stuff in a pail. When the color came out correct, the change was done. Hopefully, it’ll be available soon!




UPDATE: Part of me feels really stupid and part of me is now very happy. :beerchug:
I have identified what I believe is my problem. I tried all the recommendations given to me about properly bleeding the system and even trying Lucas Power Steering treatment with no luck. This weekend I started a search for a new/old stock pump as that was one suggestion made to me and among my searches was Ebay. One of the listings got me thinking about the pulley size and after some more research, I’ve confirmed I have the incorrect pulley.
The power steering pulley currently on my 1969 Cougar XR7 with a 390 with air, fits a 289 from 1966-68. So it looks like 2 owners before me, a used car lot, installed a 289 pump/pulley set up.
Right now I am trying to locate the proper pulley. If anyone can help, please let me know. It should be stamped on the front of the pulley “7AA”. It’s the same pulley as a 429 CJ so any help finding one is greatly appreciated.
I’m guessing my current pump is probably now “cooked” and will start with a new pump too.
Thanks again,

I believe I have one and will check for you in the morning. It is on a pump but I would gladly take it off and get it to you if needed.


Thank you.

Pulley found!
Thank you,