Porsche 1972 911 Instruction manual

Workshop manual
DR. ING. h. c. F. PORSCHE KG
STUTTGART
- ZUFFENHAUSEN

PORSCHE WORKSHOP MANUAL 911 - FROM MODEL 1972 ON
This publication contains the essential removal, installation and adjustment procedures for the
Porsche 911 vehicles sold in the USA and Canada. Components and procedures described in this manual
are identical for all types unless differences are pointed out in the text. It is assumed that the reader is
familiar with basic automotive repair procedures. Special tools required in performing certain service
operations are identified in the manual and recommended for use. Use of tools or procedures other than
those recommended in this repair manual may be detrimental to the vehicle's safe operation as well as
the safety of the person servicing the vehicle.
The Workshop Manual 911
- from model 1972 on - is subdivided into 10 Assembly Groups, delive -
red in supplements to volume I and 11.
Survey of the individual Assembly Groups:
Engine and Clutch
Fuel System
Transmission
Front Axle
Rear Axle
Brakes, Wheels, Tires
Code No.
1
Code No. 2
Code No. 3
Code No. 4
Code No. 5
Code No. 6
Pedal Controls and Manual Controls Code No. 7
Maintenance Jobs, Technical Data Code No.. 0
Body Code No. 8
Electrical System Code No. 9
For identification of the volumes, the back of the folders is provided with a transparent pocket at
the top for insertion of the pertinent type.
To find the individual repair steps quickly, each Assembly Group of this Workshop Manual is sub
-
divided into " Main Groups " , " Chapters " and " Sections " and provided with a very detailed list of
contents; refer to example on next page.
Technical Information sheets should be filed at the beginning of their respective groups. The
contents of the Technical Informations will be incorporated into the Workshop Manual at suitable
intervals. The List of Contents will be edited whenever extensions and supplements are published.
- XXXII, 1974
USA /CAN

Motor und Kupplung
Engine and Clutch
Moteur et Accouplement
Motore e Frizione

ENGINE 911 1
CONTENTS
0 - INFORMATION, DESCRIPTION, TECHNICAL DATA
0.1 Description
Engine changes
- 1972 model
Oil tank changes
- 1972 model
Oil cooler system and oil circuit schematic
Oil cooler.schematic
- 1973 model
Oil cooler schematic with cooling coil
- 1974 model
Engine, front view cross section
Engine,
' side view cross section
Specifications for 2.7 liter
- engine where differ 2.4 liter - engine
Engine changes
- 1974 model
Cross section of engine with emission control equipment
Layout of exhaust gas recirculation system
Engine cross section with emission control
- 1978/1979 models
Emission control layout
- 1980 model
0.2 Technical data
General data
Power performance curves
Technical data, Type 911T
- Continuous Injection System (CIS)
Technical data, Type 911/S/Carrera
- 1974 model
Full
- power performance - 1974 model
Technical data, Type 911S and Carrera
- 1975 model
Engine tightening data
Technical data, Type 911
- 1976 model
Technical data, Type 911 S
- 1977 model
Technical data, Type 911 SC
- 1978 model
Technical data, Type 911 SC
- 1980 model
Technical Data, Type 911SC
- from 1981Models
COOLING SYSTEM, EXHAUST SYSTEM, EMISSION CONTROL
2.1 Cooling system
Fan drive belt, replacing/adjusting

ENGINE
2.2 Exhaust system and heating
Exhaust system and heater blower, removing and installing
Exhaust system
- 1978 model
2.3 Emission control
Air injection components, removing and installing
Air pump belt, tensioning
Reactors and EGR equipment, removing and installing
Exhaust gas recirculation system
Reactor, checking for 1e:aks
Exhaust gas recirculation system, checking
Air injection system, checking
3 - OIL CIRCULATION
3.1 O'il circulation
,
Oil tank, removing and installing
Oil tank, removing and installing
- 1973 model
Auxiliary pressure relief valve, removing and installing
Auxiliary pressure relief valve, disassembling and assembling
Oil cooler coil, removing and installing
Oil cooler, removing and installing
3.2 Oil tank, removing and installing
- 1974 model
3.3 Pressure relief valve cooling coil, removing and installing
- 1974 model;
3.4 Pressure relief valve, disassembling and assembling
- 1974 model
3.5 Oil cooler coil, removing and installing
- 1974 model
Cooling coil oil lines, service installing
- 1974 model
Replacing oil lines to front oil cooler or to cooling coil
Oil cooler, removing/installing
Auxiliary pressure relief/safety valves
5 - CAMSHAFT HOUSING AND CYLINDER HEAD
j
5.1 Camshaft housing
Injection tube in camshaft housing, removing and installing
Chain tensioner, overhauling
Sealing cylinder head/camshaft housing mating surfaces

ENGINE 911 1
5.2 Cylinder head
Valve springs, installed length
Adjusting timing
6
- CYLINDERS AND PISTONS
6.1 Cylinders and pistons
Piston changes
- 1972 model
Piston and cylinder dimensions
- 1972 model
Piston and cylinder dimensions - 1973 model
Piston and cylinder dimensions
- 1974 model
" LS " cylinders and pistons, installation instructions
Pistons and cylinders, measuring
Piston and cylinder sizes, 911 SC - 1978 model
Piston weight classes
- 911 SC from 1981 models
7
- CRANKCASE AND CRANKSHAFT
7.1 Crankcase and crankshaft
Crankcase, measuring and reconditioning
'Modified flywheel installation
- 1978 model
Flywheel with pilot bearing - 1980 model
Oil filter screen and suction plate, removing/installing
Crankshaft
Crankshaft changes - 1972 model
Crankshaft dimensions
Connecting rod changes
- 1972 model
Connecting rod weight groups
Connecting rod weight groups
- 1978 model
Pistons for injection engines
Modified crankshaft drive - 1978 model
Crankshaft specifications, standard and undersize - 1978 model

Engine Description 911 1
ENGINE CHANGES - B E G I N N I N G WITH 1972 MODELS
General Information
Beginning with 1972 models, Type
911 engines have a cubic displacement of 2.4 liters
(2341 c/142.8
cu. in. )

911 Engine Description
Individual changes and changed service operations are described on the pages that follow.
Summary of Changes:
1. Technical Data
2. Crankcase
3. Crankshaft
4. Connecting rods and bearings
5. Pistons
6. Location of oil tank and oil lines
7. Clutch pressure plate, throwout bearing, and clutch disc
8. Ignition - see Group 9 (Electrical System)
9. Fuel system - see Group 2

OIL TANK CHANGES - BEGINNING WITH 1972 MODELS
General Information
Beginning with 1972 models, the oil tank is located in right rear wheelhousing in front of the rear axle.
The oil filler neck is now accessible from the outside. It is located under a hinged lid in the right rear
fender. The oil filter housing is separated from the tank and mounted on the right engine compartment
wall.
The auxiliary oil cooler under the right front fender continues to be standard equipment in Type 911s
vehicles.

OIL COOLING SYSTEM AND OIL CIRCUIT SCHEMATIC
TYPE
911 S VEHICLES (FROM 72 - MODELS)
1 Auxiliary oil cooler 6
2 Oil canler (engine mounted! 7
3 Oil pump
a Pressure pump 8
b Scavenging pump
9
4 Oil tank
5 Housing with thermostat 10
(opens to auxiliary oil 11
cooler at 83°~/1820~
Full - flow oil filter
Crankcase
- breather - to
- - -
oil tank
Oil screen
Engine thermostat (opens
to oil cooler at 83Oc/182'~
Air cleaner
Oil tank breather to
air cleaner

OIL COOLER SCHEMATIC
TYPE 911s VEHICLES (FROM 1973 - MODEL ON)
1. Oil tank
2. Pressure relief valve
3. Inlet pipe
4. Return pipe
5. Radiator coil

ENGINE CROSS - SECTION
Air filter housing
Cross
- shaft
Intake stacks
Fuel injection pump
Heat exchanger
Camshaft
Spur belt
Oil screen
Crankshaft
Oil pump
Oil screen in crankcase
Connecting rod
Piston
Cylinder
Exhaust valve
Valve guide
Oil hose connector (oil tank to oil pump)
Valve spring
Rocker arm shaft
Camshaft
Rocker arm
Intake valve
Fuel injector
Upper air shroud
Throttle valve housing
Fuel injection line
Cold start enrichment nozzle
Crankcase ventilation filter
Air filter housing retaining clips

Description 911 1

ENGINE SIDE - SECTION
Air filter housing
Air inlet tube
Fuel injection lines
Oil pressure sensor
Crankcase
Oil pump
Pressure side (to lubrication points)
Suction side (to oil tank)
Connecting shaft
Oil screen
Oil drain plug (magnetic)
Crankshaft
Connecting rod
Sprocket gear
Intermediate shaft
Heat exchanger
Exhaust muffler
Distributor drive gear
Belt pulley
V
- belt
AC generator
Upper air shroud

Description
SPECIFICATIONS FOR THE 2.7 LITER ENGINE WHERE DIFFERING FROM THE
2.4 LITER ENGINE
Crankcase:
Pistons:
Cylinders:
Ignition distributor:
Ignition timing:
Spark plugs: (gap in mm)
Throttle valve housing:
Cylinder base bore in crankcase increased from
92 mm dia to 97 mm dia.
90 mm dia instead 84 mm dia Piston pin offset by
0.4 mm instead 0.8 mm.
Cylinder walls coated with NIKASIL compound.
Cooling fins reduced from 15 to
11.
Advance curve changed.
TDC at 850
- 950 rpm
BOSCH
W 265 P 21
(0.55)
BOSCH W 260 T 2 (0.1)
BERU 265/14/3P (0.55)
BERU 260/14/3 (0.7)
Idle air ports enlarged from
3.3 mm dia to
4 mm dia.

Description 11
ENGINE CHANGES - BEGINNING WITH 1974 MODELS
1. Type 911, 911 S, and Carrera engines are equipped with NIKASIL light - alloy cylinders with a 90 mm
bore.
2. Pistons: Piston heads in Type 911 S engines are marked " A 2 " . Rype 911 pistons, by comparison, have a
deeper depression and a higher protrusion, without special markings.
3. Cylinder head: The mounting orifice for the injection valve is discontinued since the valve is
relocated to the intake stack.
4. Type 911 and 911 S engines received modified camshafts with changed valve timing.