Troubleshooting and repairing diesel engines 5th edition

Copyright © 2018 by McGraw-Hill Education All rights reserved Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher ISBN: 978-1-26-011644-1 MHID: 1-26-011644-1 The material in this eBook also appears in the print version of this title: ISBN: 978-1-26-011643-4, MHID: 1-26-011643-3 eBook conversion by codeMantra Version 1.0 All trademarks are trademarks of their respective owners Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringement of the trademark Where such designations appear in this book, they have been printed with initial caps McGraw-Hill Education eBooks are available at special quantity discounts to use as premiums and sales promotions 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the Copyright Act of 1976 and the right to store and retrieve one copy of the work, you may not decompile, disassemble, reverse engineer, reproduce, modify, create derivative works based upon, transmit, distribute, disseminate, sell, publish or sublicense the work or any part of it without McGraw-Hill Education’s prior consent You may use the work for your own noncommercial and personal use; any other use of the work is strictly prohibited Your right to use the work may be terminated if you fail to comply with these terms THE WORK IS PROVIDED “AS IS.” McGRAW-HILL EDUCATION AND ITS LICENSORS MAKE NO GUARANTEES OR WARRANTIES AS TO THE ACCURACY, ADEQUACY OR COMPLETENESS OF OR RESULTS TO BE OBTAINED FROM USING THE WORK, INCLUDING ANY INFORMATION THAT CAN BE ACCESSED THROUGH THE WORK VIA HYPERLINK OR OTHERWISE, AND EXPRESSLY DISCLAIM ANY WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE McGraw-Hill Education and its licensors not warrant or guarantee that the functions contained in the work will meet your requirements or that its operation will be uninterrupted or error free Neither McGraw-Hill Education nor its licensors shall be liable to you or anyone else for any inaccuracy, error or omission, regardless of cause, in the work or for any damages resulting therefrom McGraw-Hill Education has no responsibility for the content of any information accessed through the work Under no circumstances shall McGraw-Hill Education and/or its licensors be liable for any indirect, incidental, special, punitive, consequential or similar damages that result from the use of or inability to use the work, even if any of them has been advised of the possibility of such damages This limitation of liability shall apply to any claim or cause whatsoever whether such claim or cause arises in contract, tort or otherwise About the author Paul Dempsey is a master mechanic and the author of more than 20 technical books including Small Gas Engine Repair (now in its Second Edition), and How to Repair Brigss & Stratton Engines (now in its Fourth Edition), both available from McGraw-Hill He has also written more than 100 magazine and journal articles on topics ranging from teaching techniques to maintenance management to petroleum-related subjects Contents Foreword Rudolf Diesel Diesel basics Compression ratio Induction Ignition and combustion Two- and four-stroke-cycle Power and torque Fuel efficiency Weight Durability Conventional fuels Engine installation Trucks and other motor vehicles Stationary engines Marine engines Basic troubleshooting Malfunctions Tests Air inlet system Glow plugs Exhaust backpressure Engine mechanical Mechanical fuel systems Air blast Early common-rail Jerk pump system Inline pumps Distributor pumps Delivery valves Injectors Timers Diaphragm controls Centrifugal governors Pneumatic governors Unit injection Low-pressure system Fuel filters and water separators Electronic engine management systems Tools and resources Analog and digital Onboard computer EFI systems Sensors Actuators Lift pump EMS troubleshooting Ford 7.3L Power Stroke Cylinder heads and valves Combustion chamber types Valve configuration Before you begin Engine mechanics Scope of work Diagnosis Rigging Special considerations Cleaning Teardown Lubrication system Filters Block casting Pistons Connecting rods Crankshafts Camshafts and related parts Harmonic balancers Crankshaft bearings Assembly—major components Air systems Air cleaners Turbochargers Compressor map VGTs Aftercoolers Troubleshooting 10 Electrical fundamentals Electrons Circuits Electrical measurements Ohm’s law Direct and alternating current Magnetism Electromagnets Voltage sources Generator principles Direct-current motors Storage batteries Switches Diodes 11 Starting and generating systems Starting aids Wiring Starter circuits Solenoids Starter drives Charging systems Voltage regulation Solid-state regulators Batteries 12 Cooling systems Air cooling Liquid cooling 13 Greener diesels Diesel emissions Emissions controls Diesel debacle Biodiesel Straight vegetable oil Natural gas Compressed natural gas (CNG) LNG Renewable natural gas (RNG) Index Foreword In a world of throwaway consumer products, diesel engines are an exception Industrial engines, those built by established manufacturers such as Caterpillar, Cummins, Deutz and Daimler run for decades with only occasional repairs Several of these have been used in American pickup trucks, although car makers prefer in-house power The Ford-designed 6.7L Power Stroke follows industrial practice and, as a result, is in process of receiving a B10 rating, which means that 90% of them should run for 500,000 miles without having the cylinder heads or oil pan disturbed Smaller engines intended for commercial use have something of the same durability The subjects covered include: • Diesel operation (what distinguishes diesel engines from spark-ignition engines) • How to install stationary and marine engines • Basic troubleshooting • Cylinder head and engine rebuilding • Mechanical fuel systems • Electricity for those who are new to the subject • Electronic fuel systems • Turbochargers and associated air systems • Starting and generating systems • Air and liquid cooling systems • Emission controls This book is intended to supplement factory shop manuals, most of which are written cook-book style with little or nothing by way of explanation Cook books are okay, if the only engine you will ever work on is the one you have a manual for My aim in writing was to combine “how-to” instructions with theory Understanding is the best, most essential tool a mechanic can have The more you know the easier the work becomes and the less money you waste on throwing parts at the problem And should the job appear too demanding, an understanding of what’s involved and a familiarity of the vocabulary puts shop mechanics on notice that they are dealing with a knowledgeable customer who will not be taken advantage of That said, diesel engines are simple mechanical devices, differing from gasoline engines only in the precision of their parts Most repairs can be accomplished with no more than a good set of hand tools Things get complicated when dealing with fuel systems Special tools are needed together with an appreciation of how these systems work You must also be aware of the hazards presented by highpressure fuel and the lethal voltages that are sometimes present But the rewards of working on these beautiful engines are real Not only will you save money—shop labor charges can top $150 an hour —you will have the satisfaction that comes with accomplishment Paul Dempsey Houston, TX engine mechanics and, 196–200, 196f–199f piston failure and, 218 Oil rings, 212 Oil seals, 249–251, 251f on turbocharger compressors, 273 Oldsmobile, 20, 153–154, 153f Onan, 188, 200, 201f, 341 Onboard computers, for EMS, 98–100, 99f Onboard Diagnostics II (OBD-II), 95–96 Original equipment manufacturer (OEM), 145 boring bars and, 207 camshafts, 235 CHRAs, 274 for CR, 100 liquid cooling system hoses, 359 turbochargers, 271 for valve seats, 167 OSHA, 156 Otto engines, Overbore limits, 207 Overcooling, 351 Overhead camshafts, 152–153, 152f Overhead valves (ohv), 142, 143f, 148 Overheating: with air cooling systems, 342 coolant and, 147 to cylinder heads, 137 with liquid cooling, 348, 348t piston failure and, 219 from piston ring wear, 214 starting system armature and, 317 water pump and, 147 P Paper-element air filters, 254–255 Parallel electrical circuits, 278, 339, 340f Parameter identifier (PID), 130, 133t Parasitic loads, 40, 121t Particulate matter (PM): in diesel engine emissions, 362, 363f, 369–371 DOCs for, 372 DPF for, 369–371, 370f–372f from NG, 379 VGT and, 267f Particulate matter (PM) (Cont.): PCM See Powertrain control module PCV See Positive crankcase ventilation Peak-to-peak values, 282 Pedestal-type rockers, 149 Perkins, 237, 358, 358f Permeability, in magnetism, 285 Peugeot, 56f, 194f Phosphorus, 301 PicoScope, 96f PID See Parameter identifier Piezo injectors, 107–109, 109f Pinions: clearance for, 324f solenoid and, 324, 325f in starter drives, 323–324, 324f stop ring and, 324, 324f Pintle nozzles, 76–77, 78f, 82f Pintle-type injectors, 139 Piston: alloy, 216 assembly of, 243–246, 244f–246f clearance for, 224 compression rings with, 216 construction of, 215–217, 215f–217f crowns, 12, 260 defects in, 220 engine mechanics and, 215–224 failure modes of, 217–219, 220f forged, 216, 217f height of, 203 permissible wear to, 224 pins, 260 primary shaking forces on, 182 scoring of, 218 overheating from, 348 scuffing of, 217–218, 219 servicing of, 219–224 skirt diameter of, 220–221 spray jet for, 180, 180f for turbochargers, 260 two-piece, 217 valve damage from, 165 Piston rings, 211–212, 211f, 213f assembly of, 243, 244f durability of, 19 exhaust smoke and, 42f grooves in, 216 wear of, 221–222, 221f, 222f piston failure and, 219 wear of, 212–214 Plante, Gaston, 294 Plasti-Gage, 196–198, 246–247, 247f Platinum, 367 PM See Particulate matter Pneumatic governors, 85–87, 86f–88f Poles, in switches, 296 Pollution Control Products, 156 Poppet-valve, 113 Positive crankcase ventilation (PCV), 52, 59, 271 Positive-displacement pumps, 27 Positive temperature coefficient (PTC), 114 Power: air filters and, 52 with DI, 139 of diesel engines, 18 of four-stroke-cycle engines, 17–18 fuel and, 12 of stationary engines, 26–27 of truck engines, 23 turbochargers for, 54, 260 of two-stroke-cycle engines, 17–18 Power Stroke See Ford Powertrain control module (PCM), 98, 133t Precleaner, in air cleaners, 253–254 Precombustion chambers, 139, 140f, 159, 160f Pressure caps, for radiators, 353–354, 354f Pressure-relief valve, 109–110, 198, 263f Prestolite, 329f Primary shaking forces, on pistons, 182 Propeller-shaft angles, for marine engines, 34t Protrusion, of valves, 167, 167f PTC See Positive temperature coefficient Pulled threads, in cylinder heads, 158 Pulse frequency, in DC generators, 290–291 Pulse width modulation (PWM), 98, 98f Pump-line-nozzle (PLN) See Jerk pump systems Pushrods, 142, 143f, 150 PWM See Pulse width modulation Q Quality control (QC), 177 Quick charges, 338 R Radiators, drawdown rating for, 352, 353f fans for, 354–356 v-belt tension for, 354, 355f leaks in, 353 for liquid cooling, 343 in liquid cooling systems, 352–356, 356f pressure caps for, 353–354, 354f soldering for, 353 Radius ride, 243 Rails See also Common-rail systems for stationary engines, 27, 28f Random access memory (RAM), 98 Rankine cycle engines, Rape-seed oil, 376 Raw-water pumps, 358, 359f Reactance, in capacitors, 301 Read-only memory (ROM), 99 Relays: charging lamp, 325, 325f solenoids and, 322–323 as switches, 298–299, 299f Renewable natural gas (RNG), 385, 385f Resistance: in battery hookups, 339 electrical, in Ohm’s law, 280–281 in voltage regulators, 334 Resurfacing: of cylinder heads, 158–159 for top clearance, 170–171 Rheostats, 336–337 Ricardo, Harry, 140 Rigging, 177–179, 178f, 179f Rms See Root mean square RNG See Renewable natural gas Rocker arms: disassembly of, 148–150 IAPCV and, 128 for ohv, 142, 143f, 148 studs for, 149, 151f Rocker pivots, 150 Rocker tips, 149, 150, 167 Rockwell scale, 231 Roller tappets, 151, 151f ROM See Read-only memory Root mean square (rms), 284 Rotator cap, 144f RotoDiesel, 377 S Saddle alignment, for crankshaft bearings, 239, 239f SAE See Society of Automotive Engineers Safety filter, for air filters, 254–255, 255f Scale, in liquid cooling systems, 349 Scavenging, in two-stroke-cycle engines, 16–17, 18 SCR See Selective catalytic reduction Scraper rings, 212, 219 Scuffing, of pistons, 217–218, 219 Sealed Power Corporation, 209, 213–214 SEAT, 110 Selective catalytic reduction (SCR), 366–369, 369f Self-actuating switches, 298, 298f Self-discharge, in lead-acid batteries, 296, 337 Self-purging systems, for liquid cooling, 344–345, 344f Semiconductors, 276 Series electrical circuits, 277, 278f Series electrical circuits (Cont.): for batteries, 294 charging of, 338, 338f hookups, 339 for DC starter motors, 293, 294f Shorted electrical circuits, 282 diode failure and, 302 in starting system armatures, 318, 318f Shorting tabs, 326, 326f Shot blasters, for cylinder head cleaning, 157, 157f SI engines See Spark ignition engines Side-valve (sv), 142 Siemens, 100 Silent shafts, 182, 183f Silicon: diodes of, 301 for pistons, 216 Sine wave, for voltage, 284f Single-loop direct current generators, 291f Single-pole, double-throw switches (SPDT), 298 Single-pole, single-throw switches, 298 Single-wire electrical circuits, 278–279 Skoda, 110 Slip rings, 326, 327 Smoke: air filters and, 52 cylinder head diagnosis by, 145 delivery valves and, 75 excessive oil consumption and, 56 from exhaust, 9, 12 malfunction with, 41t–42t glow plugs and, 54 from piston ring wear, 212 solenoids and, 106 from turbochargers, 27 turbochargers and, 270t Snap rings, 223 on turbochargers, 272 Social question, Society of Automotive Engineers (SAE): air cleaner test codes of, 255 on air filters, 255 on battery hookups, 340 PID for, 130 on valves, 142 wire sizes of, 309, 309f on wiring, 309 Sodium, 142–143 SOF See Soluble organic fraction Soldering: for alternator diodes, 331, 332f diode failure and, 302 for radiators, 353 for starter system wiring, 310–311, 310f Solenoid: CR and, 103–107, 106f fuel shutoff valve and, 51f pinion clearance and, 324, 325f relay switches and, 322–323 relays and, 299 in starter motors, 299 for starter system, wiring for, 322f, 323f of starters, 320–323, 321f, 322f Solid-state, voltage regulators, 334 Solidarismus (Diesel), Soluble organic fraction (SOF), 372 Spark ignition engines (SI engines): centrifugal governors of, 82–85, 83f, 84f constant volume in, 14, 14f filters for, 193 fuel-rich mixture for, 12 horsepower of, 18 ignition and combustion in, 13 induction of, 12 pedestal-type rockers in, 149 SPDT See Single-pole, double-throw switches Specific gravity, in batteries, 336, 337f Spill ports, for inline pumps, 66, 66f Split ball gauges, 163, 164f Split fields, 319 Spray jet, for pistons, 180, 180f Stanadyne, 50f, 90, 377 Starter drives, 323–324, 323f, 324f Starter motors: cranking duration for, 305 DC, 291–293, 293f armature for, 291, 293, 294f series electrical circuits for, 293, 294f electrical circuits for, 312–314, 313f solenoids in, 299 Starters: final tests for, 320, 320f, 321f solenoids of, 320–323, 321f, 322f static tests for, 320 Starting: aids for, 304–305 air filters and, 52 compression and, 303 flywheel and, 303 glow plugs for, 304–305 lubrication and, 303 torque for, 303 Starting fluid: metering valves for, 305, 306f piston failure and, 219 for two-stroke-cycle engines, 44 Starting system, 303–324 armature for, 315–319, 316f–318f armatures, shorted circuits in, 318, 318f bearings for, 319–320 Starting system (Cont.): commutators for, 318, 318f electrical circuits of, 311–320, 312f–319f electrical system, brushes for, 314–315, 314f, 315f field coils of, 319 malfunctions of, 40 solenoid for, wiring for, 322f, 323f wiring for, 305–311, 307f, 308f, 309t, 310f, 310t, 311f Static tests, for starters, 320 Stationary engines: alignment of, 27–28 chocks for, 27, 28f, 29f installation of, 26–30, 28f–30f misalignment of, 28–30, 29f–32f motor mounts for, 27 power of, 26–27 rails for, 27, 28f thermal expansion in, 27 Stators, of alternators, 327, 331f Steam engines, 3, 18 Steel: crankshafts, 231 pistons, 215 Stewart-Warner, 200, 248, 249f Stop ring, 324, 324f Storage batteries See Batteries Straight vegetable oil (SVO), 376–379, 377f, 378f Studs, for rocker arms, 149, 151f Sulzer Brothers, 3, Sun, 73, 73f Sunflower oil, 377f Superchargers See also Turbochargers compression ratio of, 12 IDI and, 139 Supply pumps See Lift pumps Surge, 260 sv See Side-valve SVO See Straight vegetable oil Swirl chambers, 140, 141f Switches: as circuit protective devices, 299–300, 300f diaphragm, 298, 299f electrical, 296–301, 297f for glow plugs, 304 for oil pressure, 298, 299f relays as, 298–299, 299f solenoids and, 322–323 self-actuating, 298, 298f T TCE See Trichloroethylene TDC See Top dead center Teardown, 187 Technical service bulletins (TSBs), 96 Temperature See also Cooling systems; Overheating of fuel, EMS troubleshooting for, 120t for hydrometers, 336 of ignition, turbochargers and, 259 lead-acid batteries and, 296 of oil, turbochargers and, 268 pistons and, 215 sensors for, 113 Terminals, in electrical circuits, 276 TEXA Universal Diesel Truck Laptop Tool and Scanner, 95 Thermal efficiency, 9, 18, 140 Thermal expansion, 27 Thermostat: for air cooling systems, 341–342, 342f exhaust smoke and, 42f for liquid cooling system, 343–344, 343f, 356, 356f Thermostatic bypass valves, 189, 192f Third-brush generators, 291, 292f Throttle plate, 12 Throttle position sensor (TPS), 129–130 Thrust bearings, 237, 238f Time-fill stations, for CNG, 381, 381f Timers, in mechanical fuel systems, 79–81, 83f Timing, of injection pumps, 71–73, 71f–73f EMS troubleshooting for, 121t Timing gears, 19 Titanium, for turbocharger compressors, 261, 262f Titanium nitride (TnN), 145 Top dead center (TDC), of cylinders, 58, 147 Torque: converters, 345, 347f of diesel engines, 18 horsepower and, 18 of off-road trucks, 25 for starting, 303 of stationary engines, 26–27 truck motor mounts and, 25 turbochargers for, 259–260 Torsional damage, to crankshafts, 234 TPS See Throttle position sensor Transfer pumps See Lift pumps Transmission: on marine engines, 34 misalignment of, 30 truck motor mounts for, 25 Trichloroethylene (TCE), 156 Trouble codes See Diagnostic trouble codes TSBs See Technical service bulletins Tufftriding, 231, 235 Tulip valves, 144f Turbine, for turbochargers, 260–261 Turbo boost, 41, 54, 116, 121t, 257–258 Turbochargers: aftercoolers for, 268 air-cooling for, 261f air filters and, 52 air inlets for, 271 as air pump, 13 background of, 258–260 bearings for, 262, 271 as centrifugal pumps, 257f, 258 for CI engines, 258–259 compression ratio of, 12 compressor of, 260, 261f, 264–265, 264f, 273 crankcase ventilation and, 271 with DI, 139 for diesel engine emissions, 364 dismantling of, 271 exhaust and, 13, 257, 257f, 258, 271 exhaust smoke and, 42f fuel economy and, 18 fuel in, 259 as green technology, 258 IDI and, 139 inspection of, 271–272, 273f lag of, 258, 270t with liquid cooling, 345, 347f lubrication system for, 268–271 manifold pressure and, 258, 271 overhauls of, 272–274, 274f PCV and, 271 for power, 54, 260 smoke from, 27 troubleshooting of, 52–54, 54f, 268–274, 269t–270t turbine for, 260–261 VGT, 27, 265–268, 267f wastegates for, 262–264, 263f water-cooling for, 260, 261f Turbulence chambers, 140, 141f Two-piece pistons, 217 Two-stroke-cycle engines, 15–18, 16f of Detroit Diesel, 183–184 power of, 17–18 rocker arms of, 151 scavenging in, 16–17, 18 starting fluid for, 44 valves in, 16–17 Two-wire electrical circuits, 278–279 U UIs See Unit injectors Ulanet, 201, 202f Ultra-low sulfur diesel (ULSD), 21, 21t Unit injectors (UIs), 43, 73, 87–90, 88f, 89f, 100 V V-belt tension, for radiator fans, 354, 355f Valve guides, 163–165, 164f Valve lash, 173, 173f Valve lifters, 150, 236 Valve opening pressure (VOP), 44 Valve seals, 42f Valve seats, 145, 165, 166f, 167–168, 168f, 169f Valves: angle of the faces for, 145 Bedford, 144f breakage of, 165 camshaft and, 145 check, IAPCV and, 128 configuration of, 142–173 COV, 102 cylinder heads and, 137–174 delivery, for mechanical fuel systems, 74–76, 75f, 76f exhaust, 142–143, 165, 260 grinding of, 167 IAPCV, 124–128, 127f intake, 142 metering, for starting fluid, 305, 306f mushroom, 144f poppet, 113 pressure-relief, 109–110, 198, 263f protrusion of, 167, 167f removal of, 154–155, 155f servicing of, 165–167, 166f springs for, 145 sv, 142 tulip, 144f in two-stroke-cycle engines, 16–17 Vane pitch, in VGT, 266 Variable geography turbocharging (VGT), 27, 265–268, 272f, 364 A/R ratio for, 265, 265f Variable geography turbocharging (VGT): ECMs and, 265 vane pitch in, 266 Vegetable oil, 376–379, 377f, 378f Venturi constant, 85f Verbrennungskraftmaschinen, VGT See Variable geography turbocharging Vibration, 270t, 302 Vibration dampeners (harmonic balancers), 234, 237 Vickers, 62 Vila Soledade, Brazil, 377–378, 378f Volkswagen (VW), 20, 110, 139, 159, 373 Voltage, 279 in alternator, 326 Voltage (Cont.): for cold starts, 304, 305 diodes and, 301 from magnetism, 288f3 in Ohm’s law, 280 sine wave for, 284f sources of, 287 for starter system wiring, 310t Voltage regulators: alternators and, 326 diodes for, 301 external, 332–334, 332f, 334f solid-state, 334 Volumetric efficiency, of valves, 142 VOP See Valve opening pressure VW See Volkswagen W Wastegates, for turbochargers, 262–264, 263f Water: in cylinders, piston failure and, 219 for liquid cooling, 345–347 Water-cooling, for turbochargers, 260, 261f Water immersion heaters, 304 Water jacket, 349 Water pump, 356–359, 357f–359f overheating and, 147 rebuild kits for, 358, 358f Water separators, 92–93, 93f Water trap, 37 Watt, James, 18 Wear sleeves, crankshaft, 251, 251f White trucks, 49 Wilson, Charles Morrow, Wiring, for starter system, 305–311, 307f, 308f, 309t, 310f, 310t, 311f solenoids, 322f, 323f Y Yanmar, 10f aftercoolers of, 268, 360f connecting rods of, 226f crankcase breather of, 203f filters of, 193f fuel pumps, idle adjustment screw on, 51f full-floating piston pins of, 223f marine engines, 33f starting system wiring of, 307f thrust bearings of, 238f Z Zero cranking power, 335 Zollner, 260 ... include: • Diesel operation (what distinguishes diesel engines from spark-ignition engines) • How to install stationary and marine engines • Basic troubleshooting • Cylinder head and engine rebuilding... smooth and diesel engines are sometimes called “constant pressure” devices to distinguish them from “constant volume” SI engines (shown at Figure 2-4) Two- and four-stroke-cycle CI and SI engines. .. and combustion Two- and four-stroke-cycle Power and torque Fuel efficiency Weight Durability Conventional fuels Engine installation Trucks and other motor vehicles Stationary engines Marine engines