Power Steering Pump: Service and Repair
Removing and installing hydraulic pump
Information
Information:
^ In the event of a complaint that there is a leak in the hydraulic pump, the actual leak could also be at the connection point: "supply tank to reservoir" (bayonet lock area) -arrow-.
Supply tank
^ Before the hydraulic pump is replaced because of a complaint about a leak, first check the connection point: supply tank to reservoir (bayonet lock area) for leaks and for correct seating -arrow-. If necessary, replace the three O-rings in this area and/or replace the supply tank (sometimes referred to as expansion tank).
Supply tank: bayonet lock (locked)
The hydraulic pump -1- is removed and installed in the assembly with the reservoir -2-.
Hydraulic pump assembly
1 - Hydraulic pump
2 - Reservoir
3 - Rear hydraulic pump fastening point
4 - O-ring at adapter (connection between reservoir/supply tank)
5 - Fastening screws securing reservoir to hydraulic pump
6 - Support
Preliminary work
Information:
Cover engine openings (e.g. intake openings, crankcase, lines, open containers, etc.) with a cloth to prevent dirt and foreign bodies from getting into the openings.
The air-conditioning lines on the compressor do not need to be opened in order to remove the hydraulic pump. After removal, place the air-conditioning compressor on a suitable protective support (e.g. foam or neoprene).
1. Raise the vehicle.
2. Drain hydraulic fluid at the connection point, in the rear sill area on the left (dismantle underbody panel and open pressure and return lines).
2.1. Dismantle underbody panels in the center (left side).
2.2. Disconnect pressure and return lines -arrows- (unscrew). Collect hydraulic fluid in a container.
Pressure and return lines
3. Remove air cleaner housing.
4. Remove the supply tank.
Warning:
Danger of injury and material damage when using Pentosin.
^ Risk of skin irritation and damage to skin.
^ Damage to hoses and wiring.
-> Wear protective gloves and goggles.
-> In the event of contact (eyes or skin), wash immediately with water.
-> Collect emerging Pentosin.
-> Use caps to protect the wiring against soiling and damage.
-> Clean hoses and wiring immediately.
4.1. Extract Pentosin fluid from the supply tank with a pump. Dispose of extracted Pentosin according to the relevant regulations. Lay a cloth under the tank to collect any emerging Pentosin.
4.2. Remove fastening screw for supply tank from intake-air distributor -arrow-.
Fastening screws -arrow- must be replaced whenever they have been removed. Provided the screw is not micro-encapsulated, secure with Loctite 262 (at the thread) to prevent it undoing.
Supply tank
4.3. Open the bayonet lock anti-clockwise. Remove the tank. Immediately seal the lower tank opening with a suitable plug.
Bayonet lock for power-steering supply tank
5. Undo screws on the pulley -arrows-. Remove drive belt -1- and pulley.
Belt pulley
6. Remove air-conditioning compressor without opening the air-conditioning lines.
6.1. Take out connector for compressor -2- from between the intake pipes and pull apart.
6.2. Unscrew the three fastening screws -1- from the air-conditioning compressor. Lift air-conditioning compressor with the rear fastening screw and pull out of the engine. The rear screw can only be pulled out if it has been removed.
6.3. Lay air-conditioning compressor with the air-conditioning lines connected on its side on a protective support.
7. Remove distributor pipe with throttle housing and resonance tube.
Distributor pipe with throttle housing
Tuning pipe
Removing hydraulic pump
1. On the engine for the 911 Carrera S (3.8 l) remove the oil mist separator and place to one side. This is necessary (to make space) to remove the hydraulic pump. To do this:
1.1. Remove both side fastening screws -arrows-.
Oil mist separator mount
1.2. Pull oil mist separator out of the bore by turning carefully. Check sealing rings and replace if necessary -arrow-.
Oil mist separator sealing rings
1.3. Remove connections from oil mist separator. When doing this place a cloth underneath, as coolant leaks out of the bottom vent line. Turn the connections and pull off -arrows-. Take oil separator out of the engine compartment.
Oil mist separator connections
2. Disconnect return line at the reservoir/hydraulic pump.
Return line at hydraulic pump
Disassembly tool, universal NR.21
If you do not have a special tool to hand, press the red circlip forward using two plastic spatulas and pull the return line out at the same time.
3. Disconnect pressure line -1- at the hydraulic pump. When undoing the pressure line -1- (a/f 16 mm) counter at the connection piece (a/f 27 mm).
Hydraulic pump pressure line
4. Remove hydraulic pump.
4.1. Unscrew three Torx screws -2-.
Front mount for hydraulic pump
4.2. Unscrew one Torx screw M8 x 12 mm on the rear, rear fastening point -3-. Remove hydraulic pump.
Rear mount for hydraulic pump
Installing hydraulic pump
1. Place the hydraulic pump assembly -1- with reservoir -2- into the vehicle.
Hydraulic pump assembly
2. Secure hydraulic pump at front and rear and fit pressure line -1-.
Mount for hydraulic pump
2.1. Screw in three Torx screws -2- on the front of the hydraulic pump and one short Torx screw M8 x 12 mm on the rear of the hydraulic pump.
-> Tightening torque: 23 Nm (17 ftlb.)
2.2. Secure pressure line -1- to hydraulic pump. Counter at the connection piece when doing so (a/f 27 mm).
-> Tightening torque: 35 Nm (26 ftlb.)
3. Connect return line to the reservoir for the hydraulic pump.
Return line at hydraulic pump
4. On the engine for the 911 Carrera (3.8 l) fit the oil mist separator. To do this:
4.1. Check seals on the oil mist separator and replace if necessary. Move oil separator into installation position and connect all connections -arrows-.
Oil mist separator connections
4.2. Lightly rub Optimol MP3 onto the sealing rings sealing the crankcase -arrow-. Press oil separator into the crankcase bore by turning carefully.
Oil mist separator sealing rings
4.3. Fit both side fastening screws -arrows-.
Oil mist separator mount
Subsequent work
1. Fit air-conditioning compressor.
1.1. Fit air-conditioning compressor to engine housing with the rear fastening screws and screw down with the three fastening screws -1-.
-> Tightening torque: 23 Nm (17 ftlb.)
1.2. Connect the connector and position between the pipes of the intake system.
2. Fit pulley and drive belt. Pay attention to operating direction of used belts. Check once again that the drive belt is positioned correctly on the pulleys.
Secure pulley (tighten three screws -arrows-).
-> Tightening torque: 23 Nm (17 ftlb.)
Drive belt
3. Install resonance tube and throttle housing with distributor pipe.
Tighten screw-type hose clamps in correct position.
4. Connect pressure and return lines on underbody -arrows-.
Pressure and return lines
5. Check sealing rings at supply tank and reservoir (three in total) and replace if necessary.
6. Push supply tank carefully into opening in reservoir (at the hydraulic pump) until the supply tank is correctly positioned (four latches). In this position turn the bayonet lock clockwise as far as the mark or as far as it will go.
Supply tank bayonet lock
7. Fit new fastening screw for the supply tank -arrow- on the intake-air distributor. Provided the screw is not micro-encapsulated, secure with Loctite 262 (at the thread) to prevent it undoing. -> Tightening torque: 10 Nm (7.5 ftlb.)
Supply tank fastening screw
8. Fill hydraulic fluid into the supply tank, bleed the steering system and check for leaks.
Checking fluid level
9. Fit underbody panel.