Down machine, and the forum threads won't hand you torque numbers. This Gehl 502, 602, 652 Service Manual (OEM #918157) keeps every page pointed at one job: returning your compact excavator to factory spec. The hydraulic schematics map the pilot oil supply unit, main valve block, shuttle valve block, and swivel joint. Wiring diagrams cover both early and late serial builds, pre- and post-AB00473, with legend callouts for each relay, fuse, and solenoid stop circuit. Gear pump pressure testing walks P1, P2, and P3 one at a time. Set the 502 main pressure limiting valve to 3,336 psi (230 bar); torque the drive motor to 132.7 ft-lbs (180 Nm). Download it, search any spec by keyword, and pull it up on a tablet right at the machine.
What's Inside This Gehl 502, 602, 652 Manual
| System | Pages | Key Topics |
|---|---|---|
| Technical Data | 5-20 | Dimensions, Primary Dimensions / Performance, Bucket and Geometry, Lift Capacity Charts, Model Ge 502, Model Ge 602, Lift Capacity Chart, Model 502 Lift Capacity |
| Maintenance | 21-58 | Maintenance Schedule Gehl 502 - 602, Maintenance - General, Lubricants, Lubrication Chart |
| Hydraulic | 59-110 | Hydraulic System, Position of Components, Hydraulic Pump, Pilot Oil Supply Unit, Main Valve Block, Pilot Control Valves, Swivel Unit, Shuttle Valve Block |
| Diesel Engine | 111-116 | Diesel Engine Specifications (Important Diesel Engine Service Items – Model 602), Fuel Line Diagram, Battery (Cooling Water Line) |
| Electrical | 117-144 | Electrical Diagram, Legend Wiring Diagram 502 - 602, Relay Position 502, Plug Timer Relay for Pull Wiring, Starter Relay, Relay 602, Solenoid Stop Plug, Solenoid Stop Relay Plug |
| Torque Specifications | 145-148 | Hydraulic Fittings with Various Seals, With Coarse-Pitch Thread. All Torque Values Are in Lb.-Ft. Unless Marked Otherwise. |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| All Models | ||
| General Torque Specifications Location | Page 145 | p. 145 |
| Drive motor torque | 132.7 ft-lbs. (180 Nm) | p. 105 |
| Ground clearance | 1'-1" (340 mm) | p. 7 |
| Pilot oil pressure | 508 psi (35 bar) | p. 16 |
| 502 | ||
| Clearance S for Dozer Blade Cylinder (Hose burst protection valve) | 0.047" (1.2 mm) | p. 17 |
| Main pressure limiting valve Pump P1, P2 setting | 3336 psi (230 bar) | p. 16 |
| Hydraulic oil tank capacity | 16.1 gals. (61 L) | p. 16 |
| Main pressure limiting valve Pump P1, P2 | 3336 psi (230 bar) | p. 16 |
| 602, 652 | ||
| Clearance S for Dozer Blade Cylinder (Hose burst protection valve) | 0.059" (1.5 mm) | p. 17 |
| Main pressure limiting valve Pump P1, P2 setting | 3553 psi (245 bar) | p. 16 |
| 602/652 | ||
| Hydraulic oil tank capacity | 21.1 gals. (80 L) | p. 16 |
| Main pressure limiting valve Pump P1, P2 | 3553 psi (245 bar) | p. 16 |
Gehl 502, 602, 652 Common Problems This Manual Covers
Gehl 502 602 652 hydraulic functions slow, weak, or making grinding noise; bucket won't lift to capacity p. 29
Check the hydraulic oil level and top off if low; tank capacity is listed by model on page 16. Connect a pressure gauge at the test port and verify system pressure per page 29: primary pressure drop must not exceed 10% of the rated setting. Inspect all hoses and cylinder seals for external leaks before condemning the pump.
Manual Section: Hydraulic System Pressure Test and AdjustmentTracks running too loose or too tight, de-tracking during turns or on slopes p. 55
Measure track deflection midspan between the idler and sprocket. Correct deflection is 5/8"-1" (15-25 mm) per page 55. Adjust via the grease fitting on the tensioner: add grease to tighten, bleed slowly to loosen. Clear packed debris from the undercarriage before adjusting, and recheck deflection after the first hour of work.
Manual Section: Track Tension AdjustmentBoom, arm, or bucket showing excessive play or jerky stick movement during digging p. 28
Inspect every boom, arm, and bucket pin and bushing for side play before each shift. Grease all zerks per the schedule on page 28 to protect bore surfaces. If jerky movement persists, run a hydraulic pressure drop test per page 29: primary circuit loss must not exceed 10% of rated setting.
Manual Section: Maintenance Schedule Gehl 502 - 602One side stops tracking or travel feels sluggish; final drive makes high-pitched squeal p. 105
Remove the final drive cover and inspect for contaminated oil and scored gear surfaces. Verify drive motor torque at 132.7 ft-lbs. (180 Nm) per page 105. Check that all track rollers and idler wheels spin freely by hand. If one side is completely unresponsive, pull the drive motor and inspect internal seals before ordering parts.
Manual Section: Hydraulic SystemEngine idles rough or hunts at low RPM, machine feels sluggish under load p. 52
Adjust idle speed to 1050-1150 rpm at the injection pump per page 52. Inspect and replace both fuel and air filters if clogged or overdue. Verify injection nozzle spray pattern and opening pressure using service procedures on page 49. A misfiring nozzle is the most common hidden cause of low power and rough running under digging load.
Manual Section: Engine Speed Adjustment (Idle and Maximum)Frequently Asked Questions
What do the warning lights or fault codes mean on a GEHL 502/602/652?
Each indicator on the panel maps to a specific fault. H1 is the glow plug, H2 charge, H3 water temperature warning, H4 oil pressure, H5 clogged air filter, H6 check return filter, and H7 minimum fuel. Control lamps H12 through H18 cover preheating, load control, engine temperature, engine oil pressure, air filter clogged, hydraulic oil filter clogged, and overload warning.
Where can I find the service manual for a GEHL 502/602/652?
What you're viewing is the Service Manual for the GEHL 502/602/652 Compact Excavators. It carries Form No. 918157, Revision A, and was published in June 2005.
How do I troubleshoot hydraulic problems on a GEHL 502/602/652?
Run the PRESSURE TEST procedures in the Hydraulic System section. Connect a pressure gauge to the measuring ports (MP 1, MP 2, MP 3, MP 4) and check the settings at maximum engine speed along with the pressure drop. A drop exceeding 10% of the setting points to leakage, often a defective O-ring in a secondary valve.
How quickly can I access this Gehl 502, 602, 652 manual after buying?
Your download starts immediately: the full 148-page searchable Service Manual. Open it on any device, whether that's a laptop at the desk or a phone in the field.
Are there any print restrictions on this Gehl 502, 602, 652 manual?
No restrictions at all. Print individual pages, full chapters, or the entire manual. The PDF is completely unlocked.
Are there wiring harness diagrams in this Gehl 502, 602, 652 manual?
Yes, this Gehl 502, 602, 652 Service Manual includes complete electrical wiring diagrams, wire routing, and connector pinouts.
Document Quality
This is a scanned service manual with an OCR layer, allowing you to search and copy the full text. The text throughout the document is crisp and easy to read. Diagrams and illustrations are a mix; some are sharp vector graphics, while others are clear scanned images with readable labels. The pages are clean, free from significant scan artifacts, stains, or skewed content. Note that several pages are intentionally left blank.
Reviews
There are no reviews yet.