P/S pump break in -- advice needed

[RC92234]

Summer weather has finally let up so I can get to overdue projects. I gotta get to the bottom of the problems with the power steering pump replacement because it's providing *no* assist. Fluid levels are good. The pump was originally replaced because it was leaking.

After replacing the pump last year, for "break in" I did the turn the wheel all the way left then right three times. Did not seem to have any effect. Then I read here the wheels should be off the ground for that procedure, so put the front end up on stands suspending the front off the ground and repeated the all the way to the left and then the right *five* times and still no power assist.

The pump was new. What to do now? I'm thinking either drain the system and start over as if the pump were just installed, or should I assume the pump is faulty and replace it? (I do just happen to have new one on standby -- it got sent by mistake and since there was no invoice for it, they said just keep it).

Any wise words?

 

[Otto]

I believe the break in procedure you mentioned is actually the bleeding of the power steering system. If that is what you are referring to, you typically do it with the car not running, and to make it easier to turn, the tires off the ground. Turn the wheel side to side until there is no more air cycling through. Next step, check the fluid level with the car off. After that, turn the car on and ensure proper level with the pump working and if the level is good, turn the wheel side to side while the car is parked. If everything feels good, test drive and verify. With proper fluid level and some normal use, the pump will break in on it's own. I would recommend not revving over 4k for at least a few hundred miles to not stress the new pump before proper break in.

 

[SteveO_71]

Here is the procedure powersteering.com recommends:

Filling Procedure​

1. Fill the pump’s reservoir (tires on the ground)
2. Start the engine for a few seconds and turn it off (do not turn the steering wheel.) Check and refill the reservoir.
3. Repeat Step 3 until the reservoir remains full. (If you turn the wheel before the system is full, you can cause an “air bind” in the pump pressure/flow control valve that will result in diminished or NO POWER ASSIST to the power steering gearbox.)
4. With a full reservoir, start turning the steering wheel SLOWLY after starting the engine. If you hear the pump growl or moan, stop turning the wheel and turn off the engine. Check fluid level. Start the engine again; slowly move the steering wheel back and forth to expel the air.
5. Check the line for leaks. Confirm the hoses aren’t rubbing against other parts in the engine bay.
6. Air should be completely expelled within a day or 20 miles of driving. If you see fine air bubbles in the system after this time, there can be air sucking into the system. Check your return line clamps and/or replace old hoses.
   Saginaw Pumps Only: In the event you experience an “air bind” (this is rare if the above instructions are followed) remove the pressure hose from the back of the pump. Then push a very thin straight pick into the pressure port hole to release the stuck flow valve. Push it in about 6 times. You should feel the flow valve spring pushing back at your effort. Reattach the pressure hose and refill the reservoir. This should correct the problem. A 5 second video showing the process is here.