Caterpillar 3508 Diesel Engine Repair Manual Set – 1986 Edition (P/N SENR2995)

The service publications combine component specifications, system explanations, testing and repair procedures. The operation and maintenance guide adds operating instructions and scheduled care for all three industrial engine models.

Repair coverage varies by section: The disassembly and assembly publication lists the serial ranges shown above. Broader model references in shared specifications and the operation guide do not establish complete internal-repair coverage for every listed engine.

PDF Search, Bookmarks and Diagram Detail

Search and drawing access: Most technical text is searchable, but some charts and drawing labels are not. Embedded bookmarks provide access to the contents, page references and selected charts and figures. Small wiring labels require zooming.

One printable English PDF contains 664 pages total, including all publication covers, shared safety and contents pages, Army support material, the warranty page and three additional nontechnical pages.

Engine Overhaul, Fuel Testing and Shutdown Controls

The following selected coverage highlights summarize the main workshop areas. Other included topics range from the ether starting aid to jacket-water heaters.

• Engine repair: Cylinder-head, piston, liner, camshaft and crankshaft work, bearing replacement, and removal and installation of the 3508 front balancer.

• Fuel injection: Step-by-step instructions for injector removal and installation, bench testing, fuel timing, injector synchronization and fuel-setting checks.

• Governor adjustment: Woodward UG8 and Caterpillar 3161 troubleshooting, compensation, idle-speed and droop adjustments, plus air-fuel ratio controls.

• Lubrication and cooling: Oil-pump and water-pump disassembly and assembly, oil-cooler service, cooling-system tests and temperature-regulator checks.

• Shutdown protection: Hydramechanical and electric protective-system diagnosis, overspeed calibration, oil-pressure protection, reversal detection and sensor verification.

• Operation and maintenance: Starting, stopping, storage, fluid selection and illustrated service procedures organized by maintenance interval.

The repair sections suit mechanics equipped for heavy-engine work; fuel-setting adjustments specifically require governor and fuel-setting training, while the operation guide also supports new and experienced operators.

Internal Engine Work and Assembly Checks

Component data covers connecting rods, main-bearing journals, camshaft lobe lift, cylinder-liner projection and flywheel-housing runout. General tightening tables specify bolts, nuts and taperlock studs in N·m and lb-ft; a V-Belt Tension Chart supports belt checks.

Cylinder-head notes distinguish coolant-plug arrangements for water-cooled and dry exhaust manifolds. Assembly requirements also address single-use injector guide springs and prohibit torch heating during piston-pin bearing installation.

The repair notices identify cylinder-block damage from turning the engine with camshaft timing pins engaged, and injector damage or failure from striking the follower during installation.

Injector Tests and Governor Variations

The 6V4022 injector-tester procedures cover spray-orifice inspection, load-cell testing, external leakage, tip leakage and leakdown. Timing and synchronization instructions identify the 6V3139 Timing and Fuel Setting Tool Group and 6V3119 Rack Synchronizing Gauge.

Separate references: Internal injector repair is referred to Special Instruction SEHS8190. Engine-specific timing dimensions and fuel settings require the separate Fuel Setting and Related Information fiche; these references are not included.

The 3161 material distinguishes standard, torque-rise and generator-set governors, with mechanical, pneumatic and motor-operated speed controls.

Cooling, Turbochargers and Protective Circuits

Cooling diagnosis includes pressure-cap and radiator leak tests, temperature-gauge checks and regulator testing. Oil-flow and coolant-flow schematics explain bypass circuits and piston-cooling jets. Turbocharger disassembly and assembly procedures specifically identify the AiResearch TV61 and TW61, alongside vibration-damper inspection information.

Hydraulic flow paths and factory test criteria support diagnostic and repair planning by helping distinguish oil-pressure, speed-sensing and shutoff-control faults. The hydramechanical documentation separates earlier, later and alarm-equipped circuits.

Electrical references include the Step Oil Pressure charts, Reversal Detection charts, Electric Protective System Schematic and Typical Junction Box Wiring Diagram. Procedures distinguish 5N1955 and 4W2218 electronic speed switches, 7N7412 sensor verification and magnetic-pickup tests.

Battery, charging-system and starter-solenoid tests remain included. Certain alternator, regulator and starter component-specification sections are marked “Deleted” for the 3508; this does not remove all starting and charging diagnosis.

Follow the manual’s lifting and isolation precautions for heavy components, pressurized fluids and running-engine tests.

Fuel-Regulator and Injector-Test Examples

Regulator versions: The earlier fuel-pressure regulator is specified to maintain manifold pressure at 415–620 kPa; the later version specifies 415–450 kPa. These are separate configurations, rather than one interchangeable setting.

Injector bench testing: With the 6V4022 tester, acceptable load-cell pressure for a new or used injector is 3100–4100 kPa. This reading evaluates injector valve-opening behavior; it is not a direct measurement of valve-opening pressure.