1990–1999 John Deere 3029, 4039, 4045, 6059, 6068 Diesel Engine Service Manual (P/N CTM8)

John Deere Series 300 Component Technical Manual CTM8 (07JAN99) covers repair procedures and operating tests for the 3029 (S.N. —499999), 4039, 4045, 6059, and 6068 diesel engines. Coverage includes Saran-built 3029 engines and Dubuque- and Saran-built versions of the other listed models.

• Cylinder head and valves: Head removal and installation, valve-train inspection, camshaft follower measurements, valve-clearance adjustment, and torque-turn fastening procedures.

• Block and rotating assembly: Cylinder liner, piston ring, connecting rod, and main bearing inspection; crankshaft grinding guidelines, flywheel service, and wear sleeve replacement.

• Camshaft and timing gears: Camshaft, balancer shaft, and idler gear service, backlash checks, and configuration-specific timing procedures.

• Lubrication and cooling: Standard- and high-capacity oil-pump service and exploded views, oil coolers, water pump variants, thermostat testing, and water manifold service.

• Intake and exhaust: Turbocharger inspection, bearing-clearance tests, center housing and rotating assembly replacement, manifold service, and aftercooler repair.

• Fuel delivery: Stanadyne DB2, DB4, DM4, and Lucas CAV pump removal, installation, and timing; injection nozzle testing, reconditioning, and adjustment.

• Engine diagnosis: Compression, oil pressure, blow-by, and cooling-system pressure tests, plus dynamometer testing, troubleshooting charts, and engine break-in guidance.

The manual is written for experienced technicians, with essential tools identified for the service work that requires them.

Rebuild Measurements and Configuration Changes

Main bearing-to-journal clearance checks using PLASTIGAGE and micrometers help determine whether the rotating assembly remains within the listed limits. Crankshaft grinding guidance distinguishes steel and nodular iron crankshafts, ground and rolled fillets, and the permitted undersize bearing options.

Serial-specific piston pin, liner-to-block, and timing gear data separate early and later builds. The Engine—Sectional View and Crankshaft and Main Bearing Failure Analysis charts support component identification and wear assessment.

Machine-level work: Engine removal from and installation into the machine are referred to the applicable machine technical manual. The component manual concentrates on engine repair and testing.

Injection Timing, Nozzle Tests, and Fuel Faults

DB2 procedures distinguish retained and non-retained drive shafts. Dynamic timing instructions use the TIME TRAC kit JT07158 or FKM10429A; Group 199 provides the DFRG2 timing-mark transfer tool and DFRG3 cylinder liner holding fixture drawings.

Fuel checks address air ingress, restricted return lines, and drain-back, alongside troubleshooting for smoke, low power, and erratic idling. The Stanadyne Fuel Injection Pump Operation section view explains the pump mechanism. Nozzle tests cover opening pressure, chatter, spray pattern, leakage, and valve lift.

Pump service limits: Included injection-pump specification tables cover OEM applications; industrial and agricultural applications are referred to separate specifications handbooks. Internal injection-pump repair and bench testing are assigned to an authorized ADS diesel injection repair station.

Oil Flow, Cooling, and Turbocharger Service

Common Lube and Pre-Common Lube layouts distinguish bypass and pressure-regulating valve arrangements. Water pump procedures separate low-flow, standard-duty high-flow, heavy-duty high-flow, and modular designs. How the Engine Lubrication System Works and How the Cooling System Works diagrams trace fluid paths; the Aftercooler Assembly view identifies its component arrangement.

Turbocharger repair centers on housing inspection and center housing/rotating assembly replacement; complete internal disassembly requires specialist tooling and personnel. The engine-mounting section warns that oil draining through the turbocharger while an engine is turned on a rollover stand can cause hydraulic lock and severe engine damage.

Break-in guidance warns that PLUS-50 and API CG4/CF4 oils prevent proper wear-in during the first 100 hours of a new or rebuilt engine. Pressurized cooling systems and fuel injection equipment present burn and fluid-injection hazards; follow the manual's pressure-relief and handling precautions.

Starting and Charging Scope

Starter and alternator removal and installation are included. Their internal repair and testing, along with charging-circuit diagnosis, are referred to the separate CTM77 manual.

Examples of Valve Settings and Crankshaft End Play

These settings are a small sample of the adjustment and inspection specifications in the repair groups.

Cold rocker-arm-to-valve-tip adjustment is 0.36 mm (0.014 in.) at the intake valves and 0.46 mm (0.018 in.) at the exhaust valves. Checking ranges are listed separately from these adjustment targets.

For new parts using the two-piece thrust bearing, specified crankshaft end play is 0.05–0.25 mm (0.002–0.010 in.).

Searchable Text, Bookmarks, and PDF Contents

Finding procedures and drawing detail: Text search is available across the technical sections, with embedded bookmarks for component groups and individual procedures. System drawing labels are readable; small dimensions in the tool drawings benefit from zooming.

Supplied as one printable, 682-page PDF: 16 pages of front matter including the front cover, 656 pages across the technical groups, a nine-page index, and one back cover. Introductory material and intentional blank pages are already included in that total.