1998 Ford Explorer 4.0L V6 OHV Engine

[CynthiaK]

Hi,

Should the power steering pump pulley be free-wheeling when the belt is off like the other pulleys?
On mine, it is hard to turn and makes a bit of a chirp when turning by hand. When driving, as soon
as I step on the gas, the chirping sound increases. I have no issues with the steering.

Thank-you!
C

 

[fast_dave]

@CynthiaK

You have a P/S Pump that is in the final stage of failing.

That chirp (and tough to turn P/S pully) is your Explorer advising you to buy a new pump ASAP.

If the pump locks, in addition to you having NO POWER ASSIST, you risk - at minimum - shredding the Serpentine Drive Belt - which is the (1) belt that runs EVERYTHING - i.e. Alternator

Worst case would be an accident due to loss of P/S, or that the P/S pump locks which causes the Serpentine Drive Belt belt self-destruct and blow a hole in your radiator.

Rock Auto Link to your P/S Pump: 1998 FORD EXPLORER 4.0L V6 OHV Power Steering Pump | RockAuto

Rock Auto Discount Code:

5% Off until February 14, 2021 Code# 160477950146809610​

Hope that helps & Happy New Year!

 

[CynthiaK]

Thank-you for the response!

We replaced the pump and it is working good now, except for a bit of a whine when turning the steering wheel but I was told it is because there is some air in the system.

 

[EB4X]

Yes, most likely air.....bleeding should always be performed with change out...or it was but not adequately ?
Jack up front end so wheels are off the ground, take off reservoir cap... and turn steering wheel all the way back and forth repeatedly until all air bubbles have dissipated from top of fluid.

 

[C420sailor]

Did you flush the system when you replaced the pump?

If not, I’d recommend changing the fluid again soon, and check it for shiny particles. Keep changing it until it’s clean.

 

[CynthiaK]

Thank-you for the replies.

Yes, the system was flushed with the change out and we did the turning the steering wheel back and forth.

We may have to flush it again.

 

[fast_dave]

Thank-you for the replies.

Yes, the system was flushed with the change out and we did the turning the steering wheel back and forth.

We may have to flush it again.

@CynthiaK

First - Thanks for closing the loop - your participation makes the forum work

Without hearing the "whine" that you're hearing, I will throw this out there so you and your helper don't freak out.

When running a newly rebuilt pump, you will get a certain amount of break in noise as internally the pump's high carbon based pressure vanes break-in.

It may take as long as a month or two and then it'll start to quiet down.

The reason is most (if not all) of the rebuilt pumps are rebuilt in Mexico.

The "refinish" machining on the inside of the pump that the high carbon steel based pressure vanes match up with is pretty rough - that's more than likely the noise you're hearing (the vanes scraping the rough surface).

It's loud enough that you can hear it with the engine running, and the hood closed, primarily when you turn the steering wheel left and right.

About 6 months ago I replaced my P/S pump that started leaking after 100,000 miles w/ a A/C Delco Professional P/S Pump.

It too was rebuilt in Mexico, and after installed and bled it was noisy enough that I got a couple of comments "what is that noise under your hood".

After about a month - all is quiet. The vanes eventually machine/match themselves up with the rough surface they are riding on.

Hope that helps and glad you're up and running without any big issues

 

[EB4X]

Interesting Fast Dave (I have a rebuilt Cardone p.s. pump on standby for when the Lucas additive improvement wears off - I'll keep this in mind)
"as internally the pump's carbon based pressure vanes break-in." This sounds like a line out of Star Trek !

 

[fast_dave]

Interesting Fast Dave (I have a rebuilt Cardone p.s. pump on standby for when the Lucas additive improvement wears off - I'll keep this in mind)
"as internally the pump's carbon based pressure vanes break-in." This sounds like a line out of Star Trek !

@EB4X

Yeah - it used to be that as recently as the 90's P/S pumps were rebuilt in Motor City or the Great Lakes Region, then NAFTA killed that off and all it all went to Mexico...

Rebuilders in America would take the time to really clean up the finish on the inside pump, because it's the interface between that surface and the high carbon steel brushes/vanes that ensures high pressure and low noise.

Now that P/S Pumps (and starters and alternators) are rebuilt in Mexico - we've seen the quality fall far off, even in the name brands (i.e. A/C Delco Professional). We read about it all the time here in the forum - guys getting a "bad" rebuilt starter or rebuilt alternator right off the shelf. That's why guys like @donalds take the time to rebuild their own alternator

In closing, I will say that the FORD P/S pump with the attached fluid reservoir (as used on the OHV model Ex's) is the same P/S Pump that was used on FOX Body Mustangs in the 80's. Anybody that's been around a FOX Body 5.0 knows the sound of the FORD P/S pump "growl" as you turn the steering wheel L to R and vice-versa. There's a certain amount of noise "built into" the design of this particular pump. That noise brings me back to a certain '85 and '86 GT and the mantra I used to live by; "Our Lady of Blessed Acceleration, don't fail us now"