NG 900/9-3 Power Steering Pump Replacement
Overview
The power steering pump was originally made by Saginaw Industries, once a part of AC Delco and GM. It was used on a number of US made cars including some models of the Chevy Cavalier. The pump can fail due to a combination of age, low fluid level, and overheating. Common symptoms are leaks at the shaft and/or excessive noise while turning the wheel. (Note: Noise made when the wheel is turned all the way to the stop and held there is normal, not a sign of a bad pump!)
The pump is replaceable with any Saginaw CB-series pump which has the same pulley type and inlet and outlet sizes, and same flow control valve. The one shown above was rebuilt from a core for more performance-oriented steering by AGR Performance in Texas. The cost of the rebuilt pump was about $125 with all new moving parts, high temp seals, and ~40% more flow.
Replacement
Refs
Components
- Pump, Saab p/n 4647491, or
- Saginaw CB pump w. 3/4 press-on shaft, M16x1.50 outlet, 5/8 tube inlet
- O-ring, 11 x 7 x 2 mm
- Power steering fluid, 1 quart, Dot 3 or 4
Tools
- 3/8 drive ratchet
- Flex socket adapter
- 10-mm socket (air box)
- 13-mm socket and wrench (pump)
- Torque wrench (optional)
- 16-mm flare nut wrench or crow-foot
Torque Wrench Settings
- Pressure line, 21 lb-ft
- Pump mounting bolts, 15 lb-ft
References
- Saab EPC 5-0120
- Haynes Ch 9, section 4
Access
Power Steering Pump
- Remove air intake hose and filter box
- Release and lock belt tensioner
- Move the serpentine belt aside
- Plug intake tube with a towel to prevent dropping anything into the turbo intake
Power Steering Fluid
Fluid spills can be reduced by draining at least some of the fluid using the hose connections at the bottom of the reservoir before removing the pump.
Removal
Upper Bolt and Pressure Line
The pump is attached to a bracket on the engine block and to the pressure line. Loosen, but do not remove the long upper mounting bolt, and the small bracket which connects the pressure line to the pump. This will allow the pump to be removed more easily when the lower bolt is out.
Lower Bolt
Remove the lower bolt which is recessed behind the pulley, shown below. It can be reached using a flexible socket adapter or a similar tool which can reach through one of the pulley holes and clear the lower mounting bracket for the air filter box.
Power Steering Hoses
The high and low pressure lines can now be disconnected from the pump and capped or plugged to keep spills to a minimum. If the pump is only being moved aside for access to the water pump, the hoses can remain attached to the pump.
Pump
When the hoses are loose, the upper bolt can be taken out and the pump lifted out from the bracket.
Assembly
Pump
If the replacement pump did not come with a pulley, tools to remove it from the old pump and install it on the new one are available at any part store. Install pump loosely on the upper bolt, but do not tighten. Install the lower bolt, and tighten both bolts to the specified torque. Remove the caps on the pump outlet and intake only after the pump has been installed.
Hoses
Install a new pressure line o-ring and the suction line hose clamp. Attach the pressure line to the pump. Tighten the pipe fitting first, and the bracket second. Install the suction hose on the pump. Clean any spilled fluid from the pump area before replacing the serpentine belt, and make sure no small parts were dropped into the turbo air intake.
Fluid and Other Components
- Replace serpentine belt
- Refill the system with steering fluid
- Bleed system to purge trapped air
- Check for leaks
- Replace air filter box and intake hose
