The OEM #913238 manual splits the CT6-18 Turbo and CT6-18 into five systems: engine, transmission, axles, hydraulics, and electrical. Hydraulic schematics cover both variants, the wiring diagrams carry color-coded connector pinouts, and detailed exploded views map every serviceable assembly, plus a dedicated troubleshooting section. The engine chapter goes deepest: cylinder head, crankshaft, timing drive, turbocharger fault diagnosis, and fuel injection pump timing for the Bosch VP30, Bosch EPVE, and Delphi DP210. Two numbers worth knowing before you start: the M18 x 1.5 hydraulic O-ring connection torques to 5 daNm (440 lbf in), and the hydraulic return filter cartridge (#217785) changes at 500 hours. Across all 580 pages, every spec is searchable by keyword, so you can pull a figure up on a tablet at the machine instead of guessing through forum threads.
What's Inside This Gehl CT6-18 TURBO, CT6-18 Manual
| System | Pages | Key Topics |
|---|---|---|
| General Information | 5-18 | Introduction, Engine Views, Engine Identification, Safety Precautions, Engine Lift Equipment, Viton Seals, Powerpart Recommended Consumable Products |
| Engine | 19-294 | Specifications (Basic Engine Data, Data and Dimensions, Thread Sealant, Standard Torque Values, Specific Torque Values, Compression Test Data) |
| Transmission | 295-348 | Gear Box and Converter, Gear Box, Transmission Hydraulic Circuit, Transmission Hydraulic Principal Circuit, Transmission Maintenance, Pressure Checking |
| Axles | 349-514 | Introduction |
| Hydraulics | 515-564 | Exploded View: Ospb, Ospc / Ospf, Tools, Dismantling, Assembling, Max. Tightening Torque and Hydraulic Connections, Trouble Shooting, CT6-18 Hydraulic Diagram |
| Electrical | 565-580 | Electric Diagram, Contents (CT6-18: Electric Diagram, Turbo Electric Diagram) |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Hydraulic connection torque (M18 x 1,5 with O-ring) | 5 daNm (440 lbf in) | p. 547 |
| Hydraulic seals replacement | Replace all seals and washers | p. 533 |
| Hydraulic Return Oil Filter Cartridge part number | 217785 | p. 16 |
| Hydraulic Return Oil Filter Cartridge change interval | 500 H | p. 16 |
| Fuel Filter Cartridge part number | 219994 | p. 16 |
| Fuel Filter Cartridge change interval | 500 H | p. 16 |
| Dry Air Filter Cartridge part number | 219980 | p. 16 |
| Dry Air Filter Cartridge clean interval | 50 H* | p. 16 |
| Battery specification | 12 V - 145 Ah - 950 A EN | p. 9 |
| Starter specification | 12 V - 3,0 kW | p. 9 |
| Starter type | Denso E95RL | p. 9 |
| Front and Rear Tires pressure | 38 PSI | p. 10 |
Gehl CT6-18 TURBO, CT6-18 Common Problems This Manual Covers
Gehl CT6-18 engine won't crank or turns over slowly in cold weather p. 9
Load-test the battery against the 12 V, 145 Ah, 950 A EN rating on page 9, then clean the terminals and confirm every safety interlock is closed. A starter that cranks weakly should go to your nearest Perkins Dealer/Distributor for repair or replacement, since rebuilding it is not recommended. Reinstall with the mounting bolts torqued to 44 Nm (32 lbf ft).
Manual Section: ElectricalBoom won't lift or extend, hydraulic response is slow or nonexistent p. 554
Start with the hydraulic oil level: the tank holds 35-1/2 gallons, and low fluid is the most common culprit. Confirm the lifting circuit reaches 3770 PSI (260 Bar). If the return filter (part 217785) is past its 500 H change interval, replace it. The hydraulic schematic on page 554 lets you trace blocked valves or a relief circuit that is bypassing.
Manual Section: HydraulicsEngine loses power under load, black or blue smoke from exhaust p. 183
Inspect the air filter first. The fault guide on page 183 points to a dirty element as the leading cause of power loss on turbocharged machines, so clean or replace the cartridge. If smoke or sluggish power persists, measure valve tip clearance cold (inlet spec 0.20 mm / 0.008 in) and check that engine oil sits at the full 9-quart mark.
Manual Section: EngineHydraulic oil leaking from hose connections or cylinder seals, boom drifts down p. 547
Torque all M18 x 1.5 O-ring hose fittings to 5 daNm (440 lbf in) as specified on page 547. Loose fittings are the most common external leak source. If cylinders are weeping, remove and replace all seals and washers per the seal procedure on page 533. Inspect hose condition for chafing or cracking before refilling and pressure-testing the circuit.
Manual Section: HydraulicsSteering wheel hard to turn or has excessive play at low speed p. 515
Rule out low hydraulic oil and external leaks at the steering unit connections first, and snug any loose M18 x 1.5 fittings to 5 daNm (440 lbf in). Hard steering or heavy play usually means worn internal seals in the OSPB/OSPC unit. Rebuild it with the disassembly procedure starting on page 525, replacing all seals and washers.
Manual Section: HydraulicsFrequently Asked Questions
How do I clear error codes on a GEHL CT6-18?
Clearing logged 'Critical event' codes from the Engine Control Module (ECM) takes the factory passwords. Once a code is stored in the ECM, you cannot wipe it without that access. The 1100 Series Diagnostic Manual and the on-line Diagnostic Guide cover the procedure in full.
What does the warning light or fault code mean on a GEHL CT6-18 Turbo?
A diagnostic chart maps each symptom to its causes. 'Not enough power' and 'Black smoke,' for instance, trace back to a dirty air filter element (code 1), a restricted crankcase breather (code 2), or a filter that is missing or sealing poorly (code 3). On the electrical side, an alternator warning lamp that stays dark with the ignition ON, or stays lit while the alternator runs, signals a charging-system fault.
How will I receive this Gehl CT6-18 TURBO, CT6-18 Service Manual?
A 580-page Service Manual in searchable PDF, ready to download the moment checkout completes. Open it on a computer, tablet, or phone, with no shipping wait.
Are there any print restrictions on this Gehl CT6-18 TURBO, CT6-18 manual?
Yes. The PDF carries no DRM, so you can print any page or section you need for the shop. It works with any standard printer.
Does this Gehl CT6-18 TURBO, CT6-18 Service Manual have electrical diagrams?
Yes. You'll find full electrical schematics with wire routing diagrams, connector identification, and circuit descriptions.
Document Quality
This is a native digital PDF document, allowing you to search and copy the full text. The text is crisp and consistently readable throughout. Diagrams and illustrations are generally clear, though some text labels within the line drawings appear rasterized and may lose sharpness at high zoom levels. Pages are clean with no notable scan artifacts or skewed content. There are a few intentionally blank pages that serve as section separators.
Reviews
There are no reviews yet.