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Should power steering pump pulley spin freely w/o belt?

I was trying to track down a rhythmic noise that I first noticed when I had a leaking p/s pump. It seems easier to notice when cold and driving slow. Is only when car is moving.



After replacing the p/s pump, noise still there (but no more leaking p/s fluid). replaced that p/s belt recently and turned the p/s pump pulley to see if it was catching on anything. It seemed to turn smoothly, but not freely. Is that how a p/s pump pulley should turn?

It won’t spin freely like an AC compressor pulley will, because the pulley is always connected to the pump portion and always moving fluid when turned. An AC pulley is disconnected from the compressor when the clutch is deenergized, so it’ll spin freely.

I hope that helps.

It helps rule it out. But what can make the rhythmic sound. I always thought it was p/s related. Can an a/c compressor that is not used make a rhythmic sound? It is puzzling.

Under what conditions does the rhythmic sound occur? Is it affected by the speed of the vehicle or the speed of the engine? Is it affected by the AC being turned on and off?

It seems to go with the speed of the vehicle so if I was moving slow and revved the engine, the sound would not speed up. I don’t notice it when I am going faster either. It was chilly (relatively speaking) here this morning and if was louder than I remembered which made me wonder if that change had to do with my replacing the p/s belt. I wondered about pulley bearings but I don’t know if there are bearings on it if it just slides onto the p/s pump shaft. Have not tried turning a/c on and off to test. Right now I have the evaporator out and those lines taped. Can an a/c system take my turning it on and off with the a/c system open and no refrigerant in it? Thanks.

Year, make, model, mileage???

89 honda accord lxi 485k

485K? Congratulations!

Since it’s relative to the vehicle speed rather than the wngine speed, you can safely eliminate all engine components and candidates. It almost has to be somewhere in the rolling stock. Tires worn low will often exhibit rhythmic noise. Considering the car’s high mileage, wheel bearings are a real possibility also.

Jack up the corners, spin the wheels, and see if you hear the bearings in one of them. Also, check the wear on the tires. If they’'re nearing the wear bars they’re an excellent candidate for a cause. Or, if when brushing your open hand over the thread surface you feel any anomolies the tires are an excellent possibility as a source of the sound…and the root cause could be the source of the anomoly…alignment, worn out struts, worn suspension parts, whatever.

Post back.

I coast downhill and I try not to break the sound barrier frequently.

Tires almost new with no effect on the sound. Has got to be from something that rotates or something that rubs on something rotating. Can safely test the a/c when I hear the noise even though a/c system is open? I will pay close attention for more clues as it will not let me forget I have not figured it out yet and fixed it.

If it were the AC system it would be affected by the speed of the engine and by whether or not the AC was engaged. That not being the case, you can safely dismiss the AC as a possible cause.

Since the tires are new, I’m inclined to suspect a wheel bearing.