If you are a celebrity in America these days, it’s nearly a requirement to spend at least a week in some trendy, beach rehab facility. Thankfully, we’re not celebrities, but one of our junkyard power-steering pumps recently suffered from leak issues and cried out for rehab, so maybe we’re more tragically hip than we thought. With our minds now cleared from a synthetic power-steering-fluid-induced haze, we thought it might be interesting to show you how easy it is to put your classic GM Saginaw power steering pump through rehab and have it come out a clean, happy, and fully functioning member of our high-performance society.
The Saginaw power steering pump first made its appearance on GM cars in 1960. The early pumps used a threaded 5⁄8-inch-pulley-shaft-diameter fitted with a woodruff key. Later, GM changed to a larger, 3⁄4-inch shaft minus the threads and woodruff key, converting to a press-on pulley. According to RockAuto information, GM was still using this pump in some LS truck applications as late as 2009. The fittings and fasteners in later pumps merged to metric at some point but retained the same basic pump configuration, with its integral fluid reservoir. The ’65 and ’66 big-block Chevy applications used a smaller pump housing that relied on an external reservoir. If you like the idea of a separate reservoir, Original Parts Group (OPG) reproduces that pump cover. One thing that makes the Saginaw power steering pump so popular is that the same basic reseal kit will service all pumps between 1960 and 2009, and you can find one from RockAuto for less than $10.
We mentioned that the Saginaw power steering pump went metric at some point in the later ’70s, but we discovered that the thread pitch on the high-pressure output fitting that screws into the pump is so similar that the older SAE output fitting will screw right into the metric-pump body. This is important because the older pumps use inverted-flare fittings, while the newer ones use a Saginaw O-ring fitting. So if you want to update your ’60s GM pump with a newer ’90s Saginaw power steering pump from the junkyard, the exchange is a snap. In most cases, even pump housings will interchange. If your pump housing is beat up, Tuff Stuff offers both natural and chrome housings that will fit most applications. So this means you could snatch a newer pump out of the junkyard, slip on your original pump housing (or a new one from Tuff Stuff), add new seals, and have a virtually new power steering pump for very little coin. Plus, you can reuse your original pressure fitting to retain your original high-pressure hoses, so you don’t have to buy new hoses. There’s also a smaller, late-model power steering pump called the Type II that we have some tricks for, but we’ll save for a later story.
How to bleed power steering pump
If you also replaced the power steering box, there is a simple bleeding operation you can perform that will eventually save you lots of time. Power steering is just like any other hydraulic system in that it will work best with no air in the fluid. So with a dry pump and box, fill the pump reservoir with fluid, and then with the front tires off the ground, manually turn the wheels lock to lock. This will force air out of the box and lines. Do this several times, and refill the pump with fluid as needed, until no more air bubbles appear in the reservoir. Now you can start the engine and slowly run the steering lock-to-lock. The system should not create any mechanical whine. If the system whines when running, there is still air in the system and you will have to wait 12 to 24 hours for that air to exit the system. You could also try applying vacuum to the system by drilling a hole and sealing a tube in a spare pump lid plumbed to a vacuum pump in order to draw the air out of the system.
|Gates seal kit
|Dorman reservoir cap
|Royal Purple synthetic PS fluid
|Borgeson flow valve-shim kit
|PS cover for remote reservoir
|AFCO PS hose kit w/steel fittings
|AFCO PS fluid
|Power steering pulley tool, OTC
|Tuff Stuff reservoir, left return tube
American Fabricating Company (AFCO); 800/632-2320; AFCORacing.com
Borgeson; 860/482-8283; Borgeson.com
Harbor Freight; 800/423-2567; HarborFreight.com
Original Parts Group (OPG); 800/243-8355; OPGI.com
RockAuto; 866/762-5288; RockAuto.com
Royal Purple; 888/382-6300; RoyalPurple.com
Tuff Stuff; 800/331-6562; TuffStuffPerformance.com
After pressing off the pulley, remove both bolts on the back side of the reservoir and rem
There are two styles of high-pressure fittings: the SAE with an inverted flare (top photo)
There are two styles of high-pressure fittings: the SAE with an inverted flare (top photo,