Volvo D12 User manual

Service Manual
Trucks
Group 250–600
Intake and Exhaust System
D12, D12A, D12B, D12C
PV776-TSP144524

Foreword
The descriptions and service procedures contained in this manual are based on de-
signs and methods studies carried out up to August 2000.
The products are under continuous development. Vehicles and components produced
after the above date may therefore have different specifications and repair methods.
When this is believed to have a significant bearing on this manual, supplementary ser-
vice bulletins will be issued to cover the changes.
The new edition of this manual will update the changes.
In service procedures where the title incorporates an operation number, this is a refer-
ence to an S.R.T. (Standard Repair Time).
Service procedures which do not include an operation number in the title are for gen-
eral information and no reference is made to an S.R.T.
The following levels of observations, cautions and warnings are used in this Service
Documentation:
Note: Indicates a procedure, practice, or condition that must be followed in order to
have the vehicle or component function in the manner intended.
Caution: Indicates an unsafe practice where damage to the product could occur.
Warning: Indicates an unsafe practice where personal injury or severe damage to the
product could occur.
Danger: Indicates an unsafe practice where serious personal injury or death could oc-
cur.
Volvo Trucks North America, Inc.
Greensboro, NC USA
Order number: PV776-TSP144524
© 2000 Volvo Trucks North America, Inc., Greensboro, NC USA
All rights reserved. No part of this publication may be reproduced, stored in
retrieval system, or transmitted in any forms by any means, electronic, me-
chanical, photocopying, recording or otherwise, without the prior written
permission of Volvo Trucks North America, Inc..

Contents
General .................................................................................................... 3
Specifications ......................................................................................... 5
Intakeand Exhaust System ..................................................................... 5
Tools ........................................................................................................ 7
Special Tools ......................................................................................... 7
Special Equipment ................................................................................. 8
Design and Function ............................................................................. 9
Intakeand Exhaust System ..................................................................... 9
Preheater ............................................................................................... 9
D12C ................................................................................................. 9
Engines without Preheater ................................................................ 10
Engine Brake....................................................................................... 11
D12C ............................................................................................... 12
Crankcase Ventilation .......................................................................... 18
D12C ............................................................................................... 18
Exhaust Pressure Governor ................................................................ 19
D12C ............................................................................................... 21
EPG Control Valve............................................................................ 22
D12A ............................................................................................... 22
D12B ............................................................................................... 22
Air Restriction Indicator ....................................................................... 23
Turbocharger ........................................................................................ 24
D12A ............................................................................................... 24
Exhaust Manifold ................................................................................. 25
Tightening Sequence ........................................................................ 26
Troubleshooting ................................................................................... 27
Air Restriction Indicator,Checking ...................................................... 27
Service Procedures ............................................................................. 29
Air Filter Element, Replacement ......................................................... 29
IntakeManifold Gasket(s), Replacement ............................................ 30
Removal .......................................................................................... 31
Installation ....................................................................................... 31
Turbocharger,Replacement ................................................................ 32
Removal .......................................................................................... 32
Installation ....................................................................................... 33
Exhaust Manifold Gasket(s), Replacement ......................................... 34
(Turbocharger Removed) ................................................................... 34
Exhaust Pressure Governor,Replacement ......................................... 35
Exhaust Pressure Governor,Overhaul ............................................... 36
(Unit Removed) ................................................................................. 36
Disassembly .................................................................................... 36
Assembly ......................................................................................... 37
Charge Air Cooler Leak Test, Checking .............................................. 39
System Check...................................................................................... 41
Boost Pressure,Checking ................................................................... 41
Exhaust Backpressure,Checking ........................................................ 42
Pressure Testing Outlet Location ...................................................... 42
Backpressure Measuring Techniques ............................................... 42
Feedback
Operation Numbers1

2

Group 25 Intake and Exhaust System General
General
W2003244
D12C Engine
This information covers the Intake and Exhaust System for the D12, D12A, D12B, and
D12C engines.
3

4

Group 25 Intake and Exhaust System Specifications
Specifications
Intake and Exhaust System
Maximum Restriction (Rated speed full load) ............................................................................... 6.2 kPa (H20) (25 in.)
Air Cleaner torque
Plastic .......................................................................................................................................... 9 ± 2 Nm (7 ± 2 ft–lbs)
Metal ......................................................................................................................................... 20 ± 2 Nm (15 ± 2 ft-lbs)
For Specifications, including torques, refer to:
Service Manuals 200–890, Specifications, D12C
200–850, Specifiications, D12B
200–820, Specifications, D12A
IMPACT Function Group 25
Info Type: Specifications
5

Group 25 Intake and Exhaust System Specifications
6

Group 25 Intake and Exhaust System Tools
Tools
Special Tools
Servicing the VE D12 intake and exhaust systems requires the following special tools.
The tools are available from parts departments of Volvo Trucks North America, Inc.
When requesting tools, provide the appropriate number, preceded by ”999”, for exam-
ple, 9992610.
W0000406
9992610 Drift for overhauling exhaust pressure
governor
9996065 Gauge for checking boost pressure
9996666 Union for checking boost pressure
9996662 Pressure gauge
9996831 Vacuum gauge for checking pressure
drop indicator
9998225 Hollow drift for overhauling exhaust
pressure governor
9998246 Drift for overhauling exhaust pressure
governor
9998288 Connecting washer for leakage test of
charge air cooler
9998289 Sealing washer for leakage test of
charge air cooler
7

Group 25 Intake and Exhaust System Tools
Special Equipment
Like the special tools, the following are available from the parts department of Volvo
Trucks North America, Inc.. When requesting tools, provide the appropriate part num-
ber.
W0001840
1159794 Torque wrench 10–100 Nm (7–73 ft-lb)
W0001841
1159795 Torque wrench 40–340 Nm (30–250 ft-lb)
W0001842
1159796 Torque wrench 150–800 Nm (110–590 ft-lb)
8