I think I broke my PS pump

awing

Member
Jul 29, 2019
24
10
13
38
Westport, MA
I finally have the car on the road, and maybe like 600 miles total on it. The power steering pump is a new/refurb from oreilly's, I only replaced it a year ago because I cracked the plastic housing removing the old engine being careless.

Rack is original to the car, guessing 80-100k miles. Fluid is new and topped off. Unknown ball joints, probably original. Maximum motorsports solid steering shaft and solid bushing kit, stock k member. Underdrive crank pulley. Everything was great until I raised my RPM limit to 6800 and went testing, after the first pull the steering was "grumbly" like it would pop into place instead of being smooth. I've kept driving it and the steering effort is going up dramatically.

Did I get a marignal pump? Do the stock pumps not like RPM? Thinking of trying to rebuild it myself and flushing the rack out. I just hate removing the SN95 PS pulley.

I know there are a lot of variables to consider, but the solid bushings were a great upgrade for the loose steering I used to have, and I don't think that's the problem here - unless the rack moved?
 
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90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
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These pumps aren't really high rpm pumps. That can cause cavitation in the fluid and cause fluid to push out of the cap. In autoX people extend the pump reservoir neck to help with that. Make sure your tire rod ends are tight. Make sure the headers aren't too close to the u joints in the shaft....or the shaft itself. Can feel weird if they are making contact.
 

awing

Member
Jul 29, 2019
24
10
13
38
Westport, MA
These pumps aren't really high rpm pumps. That can cause cavitation in the fluid and cause fluid to push out of the cap. In autoX people extend the pump reservoir neck to help with that. Make sure your tire rod ends are tight. Make sure the headers aren't too close to the u joints in the shaft....or the shaft itself. Can feel weird if they are making contact.

The shaft clears my headers okay, I'm sure something went wrong in the rack or pump. I was running some generic power steering fluid, I wonder if a new pump would benefit from good ATF?
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
5,982
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Yes....use ATF....
 

revhead347

Apparently my ex-husband made that mistake.
15 Year Member
Jun 14, 2004
8,831
1,477
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Acworth, GA
The factory pump uses ATF Type F fluid. To get bubbles out of the system, jack the front end of the car up, remove the reservoir cap, start the engine, and turn the steering wheel lock to lock a few times. See if that fixes it.

Kurt
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
I'm pretty sure the cap on my 89 gt ps pump says use power steering fluid only. I'll check later to confirm.
I know the older systems used F type fluid.
 

revhead347

Apparently my ex-husband made that mistake.
15 Year Member
Jun 14, 2004
8,831
1,477
214
41
Acworth, GA
I'm pretty sure the cap on my 89 gt ps pump says use power steering fluid only. I'll check later to confirm.
I know the older systems used F type fluid.

Check your owner's manual to be sure. "Type F, Ford put that :poo: on everything."

Kurt
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
19,877
6,685
193
polk county florida
Curiosity got the best of me so I checked, the cap says power steering fluid, the assembly manual says power steering fluid and in parentheses (ATF) and also lists type F trans fluid so it can be confusing. I use power steering fluid not ATF. I would guess it does not matter as long as you use one or the other. :shrug:
 

Blown88GT

Founding Member
Nov 13, 1999
2,171
518
164
Palm Beach Gardens, FL
For the O'Reilly pump, use O'Reilly PS fluid. If it goes bad, they can't say you used the wrong fluid.
The pumps are noisy until you get every last bit of air out of them. I did the lock to lock thing with the front wheels off the ground. Helped some. A better method is pull a vacuum on the reservoir. There's a little tiny hole in the cap. Also, don't fill to the mark on the dipstick or it will puke out the vent hole.