Part of the Doosan Repair Manuals.
Looking for the Doosan DX27Z shop manual PDF? All 586 pages of this factory shop manual (OEM #K1028288E) cover the zero-tail-swing track excavator, from swing bearing to bucket pins. The hydraulics section alone walks you through the main pump, swing motor, travel motor, center joint, and main control valve, with teardown and rebuild steps for every cylinder on the machine. You also get full electrical schematics, hydraulic schematics, standard torque tables, and track assembly procedures for the undercarriage. Set worm-drive hose clamps under 44 mm to 20-30 in-lb, and know the hydraulic tank takes exactly 30 liters before you crack a fitting. Your excavator is down; forum threads won't lift it. This bookmarked PDF opens on any device, so search the spec, walk to the machine, and fix it.
What's Inside This Doosan DX27Z, DX35Z Manual
| System | Pages | Key Topics |
|---|---|---|
| Safety | 5-50 | Track Excavator Safety |
| Specifications | 51-76 | Specification for DX27Z |
| General Maintenance | 77-114 | General Maintenance Procedures, Standard Torques |
| Upper Structure | 115-132 | Cabin, Swing Bearing |
| Lower Structure and Chassis | 133-162 | Track Assembly |
| Engine and Drive Train | 163-172 | Drive Coupling (Main Pump) |
| Hydraulics | 173-525 | Accumulator, Center Joint, Cylinders, Swing Motor, Travel Motor, Main Pump, Main Control Valve, Remote Control Valve |
| Electrical System | 526-560 | Electrical Schematic (DX27Z) |
| Attachments | 561-586 | Working Attachments, Bucket |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Hydraulic tank capacity | 30 liters | p. 66 |
| Fuel tank capacity | 30 liters | p. 66 |
| Torque for Worm Drive hose clamp (Under 44 mm / 1-3/4 in Open Diameter) | 20 - 30 in lb | p. 108 |
| Torque for Worm Drive hose clamp (Over 44 mm / 1-3/4 in Open Diameter) | 40 - 50 in lb | p. 108 |
| Cabin weight | 240 kg (529 lb) | p. 123 |
| Recommended viscosity range | 16 ~ 36 mm2/s | p. 329 |
| Engine Coolant Temperature Sensor Input Specification (50°C) | 350 Ω | p. 549 |
| Engine Coolant Temperature Sensor Input Specification (80°C) | 118 Ω | p. 549 |
| Operating Weight | 2.71 tons | p. 66 |
| Main Relief Set Pressure | 220 kg/cm2 | p. 66 |
| Fuel Tank Capacity | 30 liters | p. 66 |
| Hydraulic Tank Capacity | 30 liters | p. 66 |
Doosan DX27Z, DX35Z Common Problems This Manual Covers
Doosan DX27Z main pump whining under load, bucket and boom respond slowly to lever input
Check hydraulic oil level and condition first; a low tank pulls air and makes the pump whine. Verify oil viscosity falls within 16 to 36 mm2/s per the chart on page 329. Test main relief pressure against the 220 kg/cm2 setting on page 66, then follow the abnormal noise and insufficient flow steps in Main Pump Troubleshooting.
Manual Section: Main Pump Troubleshooting p. 329Excavator pulls to one side when traveling, one track slower in both speed ranges
Test pilot pressure at each travel spool and compare lever stroke side to side; the travel control valve operates through operating angles of plus or minus 10 and 12.4 degrees, per page 481. Inspect the counter balance valve and two speed control valve on the slow side, and clean sticking spools before replacing parts.
Manual Section: Travel Motor Troubleshooting p. 481Engine cranks slowly or will not start, gauge readings erratic on the instrument panel
Check battery terminals and ground straps for corrosion before condemning the starter, and never short across starting motor terminals to jump the engine; that destroys the motor. Test sender circuits against the values on page 549: the fuel level sender reads 10 ohms full and 90 ohms empty. Trace circuit faults with the wiring diagram on page 560.
Manual Section: Electrical System p. 549Boom and arm cylinders drift down with levers in neutral, machine parked overnight
Inspect the main control valve spools for scoring and check the load holding sections for contamination holding a poppet off its seat. Verify relief operation against the valve's 24.5 MPa rated pressure listed on page 380. Clean spool bores with fresh oil, replace worn spool seals, and run the cylinder drift checks in Main Control Valve Troubleshooting.
Manual Section: Main Control Valve Troubleshooting p. 380Black smoke under load with power loss, air filter element clogging every few weeks
Remove the air cleaner element and inspect for dust bypass; a torn seal dusts an engine fast. Clean the housing, install a new element, and torque worm drive hose clamps under 44 mm to 20 to 30 in lb per page 108. Clear packed dirt, grease, and debris from the engine compartment while you are in there to cut fire risk.
Manual Section: General Maintenance p. 108Frequently Asked Questions
What are the torque specifications for standard metric fasteners on the DX27Z?
The torque values for standard metric fasteners depend on the grade and diameter of the bolt. For example, an M10 x Std bolt of grade 8.8 requires 4.4 kg•m (31.18 ft lb) of torque, while an M10 x 1.25 bolt of the same grade requires 5.0 kg•m (36.16 ft lb). p. 104
What is the maintenance interval for changing the hydraulic oil on the DX27Z?
The hydraulic oil should be changed every 2000 hours of operation or once a year, whichever comes first. This interval may need to be shortened depending on the degree of fouling and the thermal load condition of the hydraulic oil. p. 333
What is the procedure for checking the hydraulic cylinder natural drop?
To check cylinder tightness, put a full load of dirt in the bucket, extend the arm cylinder 20-50 mm, and retract the boom cylinders 20-50 mm. After 5 minutes, the bucket cylinder should not show more than 40 mm of change, and the arm and boom cylinders should not fall more than 10 mm. p. 75
What is the tightening torque for the cartridge valve on the track tension adjusting cylinder?
The cartridge valve on the track tension adjusting cylinder should be tightened to a torque of 6 to 9 kg•m. p. 141
What is the recommended viscosity range for hydraulic oil used in the main pump?
The recommended viscosity range for the hydraulic oil is 16 to 36 mm²/s. The oil used must be a general petroleum hydraulic oil or wear-resistant hydraulic oil equivalent to ISO3448, VG32-56. p. 329
How quickly can I access this Doosan DX27Z manual after buying?
A 586-page Shop Manual in searchable PDF format, available the moment you complete checkout. View on computer, tablet, or phone, with no shipping wait.
Can I print this Doosan DX27Z manual?
Zero restrictions. The PDF is DRM-free. Print whatever sections you need to take out to the shop. Standard letter or A4 paper works.
