Take note of the measured refrigerant oil quantity (Vold).

Check the refrigerant oil quantity of the total system (Vtotal = 170 cm³) and add refrigerant oil
if necessary.

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4.2.1

Calculate the refrigerant oil quantity of the total system (air conditioning) = Vtotal
using the following formula:
Vtotal = Vcompressor new + (Vremoved + Vold) + Vsafety
•
•

Vtotal = Filling capacity 170 cm³
Vsafety = Filling capacity 20 cm³

Sample calculation:
Vtotal (170 cm³) = Vcompressor new (135 cm³) + Vremoved(X1) + Vold(X2) +
Vsafety(20 cm³)
4.3
5

Fill the air-conditioning compressor.

Install new air-conditioning compressor.
5.1

Disconnect rigid line  Figure 10 -3- at the
compressor.
5.1.1

Unscrew hexagon-head bolt 
Figure 10 -1-.

5.1.2

Unscrew union nut  Figure 10 -2-.

Figure 10
5.2

Insert air-conditioning compressor and fit
using standard screws  Figure 11 -2- at the
front  Figure 11 -1- and rear  Figure 11
-2-.

5.3

Set position of high-pressure hose and screw
on securely.

Figure 11

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8734

8

Screw union nuts  Figure 12 -3from high-pressure hose  Figure
12 -2- on the rigid line  Figure 12
-1-.

Figure 12
5.3.2

Set distance X between collar on
high-pressure hose  Figure 13 -1and center of pulley  Figure 13
-2-.
X

– = 87 mm

Figure 13
5.3.3

Mark position of the lines  Figure
14 -1-.

5.3.4

Remove rigid line from the
compressor.

Figure 14

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5.3.5

Position rigid line  Figure 15 -2and high-pressure hose  Figure
12 -1- with respect to each other in
accordance with the markings.
Tighten union nut.
Tightening torque 36 Nm
(27 ftlb.) +/-3 Nm (+/-2 ftlb.)

Figure 15
5.3.6

Screw rigid line securely on the
compressor.
1
2

– Union nut
– Screw, M6

Union nut  Figure 16 -1-:
Tightening torque 36 Nm
(27 ftlb.) +/-3 Nm (+/-2 ftlb.)

Figure 16
5.4

Install new low-pressure hose  Figure 17
-1-.
5.4.1

Route low-pressure hose upwards.
Screw in union nut  Figure 17 -2on connecting line (on vehicle side)
loosely by hand.

5.4.2

Route low-pressure hose above the
high-pressure hose to the rear to
the compressor  Figure 17 -3-.
Tighten union nut on the
compressor.
Tightening torque 33 Nm
(24 ftlb.) +/-3 Nm (+/-2 ftlb.)

Figure 17

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ENU

8734

8

Insert strut (for secondary air injection pump)
 Figure 18 -3-.
5.5.1

Fit V-belt for compressor  Figure
18 -1-.

5.5.2

Loosen hexagon nut  Figure 18
-2-.

5.5.3

Position strut and screw in
hexagon-head bolt  Figure 18 -4-.

Figure 18
5.6

Install new strut (for air-conditioning
compressor)  Figure 19 -2-. Screw in
hexagon-head bolt  Figure 19 -1- loosely by
hand.

5.7

Tension the air-conditioning compressor
V-belt.

Figure 19
Information

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Re-use eye bolt  Figure 20 -5- and hexagon nut  Figure 20 -6- from the
standard tensioning device.
5.7.1

Fit tensioning device for V-belt 
Figure 20 -6- for air-conditioning
compressor.
1
2
3
4
5
6

– M10 hexagon nut,
self-locking DIN 985
– M10 washer DIN 125
– M10 washers (25x4) DIN
7349
– Hexagon-head bolt, M10 X
50 DIN 933
– Eye bolt
– Hexagon nut, M8

Figure 20

5.7.2

Check the tension by pressing your thumb in the centre of the V-belt. The belt
should press in by approx. 10 mm.

5.7.3

Secure the air-conditioning
compressor.

Figure 21

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8

Tighten hexagon-head bolt 
Figure 22 -1-.

5.8

Tension V-belt for secondary air injection
pump.

5.9

Connect plug connection for solenoid switch.

Figure 22
6

Screw on and tighten union nut  Figure 23 -1- on
low-pressure hose. Counter at the lock nut  Figure
23 -2-.

7

Fill the air-conditioning system and perform function
test.
7.1

Connect high-pressure line and low-pressure
line from the air-conditioning service station
to the respective valve.

7.2

Add refrigerant oil.
7.2.1

ONLY for equipment WITH integrated oil filling system:
•
•

7.2.2

Figure 23

ONLY for equipment WITHOUT integrated oil filling system:
•
•
•

7.3

Enter the measured refrigerant
oil quantity.
Allow the equipment to take in
the refrigerant oil.

Start the vacuum pump.
At the start of the vacuum phase, add the measured quantity of refrigerant oil
using an oil injector or a hose disconnected from the servicing equipment.
Re-connect the hose to the servicing equipment immediately after adding the
oil.

Evacuate the air-conditioning system.
7.3.1

Evacuate the air-conditioning system for at least 20 minutes.

7.3.2

If the air-conditioning system was open for a long time, evacuate the system for up
to 120 minutes.

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NOTICE
Excessively high pressure in refrigerant circuit
•

Risk of damage to air-conditioning compressor



Do not allow the low-pressure gauge to exceed Nominal value 43.5psi bar (3) at any time.
7.4

Fill the air-conditioning system.
7.4.1

Using the servicing equipment, add the refrigerant quantity stated in the manual
into the air-conditioning lines.
Refrigerant quantity: Filling capacity 850 g +/-25 g

7.4.2

Start the engine and carry out a leak test.

7.4.3

Check the performance of the new
air-conditioning compressor.
1
2
•

•

– Low-pressure display
– High-pressure display
Low pressure at an engine
speed of approx. 950 – 2,000
rpm = approx. 14.5 – 29 psi
(1.0 – 2.0 bar)
High pressure at an engine
speed of approx. 950 – 2,000
rpm = approx. 174 – 290 psi
(12.0 – 20.0 bar)

To reach the high pressure
values, switch off/disconnect the
condenser blower if necessary.
Figure 24

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8734

8

Temperature measurement on
dashboard.
•

8

ENU

Temperature difference in the
centre vent area (dashboard)
after approx. 20 minutes =
approx. 41° F (15° )C.

Concluding work
8.1

Disconnect high-pressure line and
low-pressure line from the air-conditioning
service station.

8.2

Screw protection caps onto the respective
valve.

Figure 25
8.3

Install air intake hose  Figure 26 -1-.

8.4

Install underbody panelling.

Figure 26
87031700:

Refrigerant drained and filled
Without:
Includes:
Checking leak-tightness using leak tester
Checking cooling output of air-conditioning system.

Labor time: 130 TU

87345500:

Compressor replaced
Includes:
Replacing intake pipe (low-pressure hose).
Without:
Draining and filling refrigerant.

Labor time: 133 TU

Important Notice: Technical Bulletins issued by Porsche Cars North America, Inc. are intended only for use by professional automotive technicians who have attended Porsche service training
courses. They are written to inform those technicians of conditions that may occur on some Porsche vehicles, or to provide information that could assist in the proper servicing of a vehicle. Porsche special
tools may be necessary in order to perform certain operations identified in these bulletins. Use of tools and procedures other than those Porsche recommends in these bulletins may be detrimental to the
safe operation of your vehicle, and may endanger the people working on it. Properly trained Porsche technicians have the equipment, tools, safety instructions, and know-how to do the job properly and
safely. Part numbers listed in these bulletins are for reference only. The work procedures updated electronically in the Porsche PIWIS diagnostic and testing device take precedence and, in the event of a
discrepancy, the work procedures in the PIWIS Tester are the ones that must be followed.

© 2018 Porsche Cars North America, Inc.

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Feb 22, 2018
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