A slipping PTO clutch or a lift that won't hold the implement mid-season is the failure this book was written for. This Fiat 566 shop manual PDF runs 252 factory pages under OEM number 603.54.228.00 and covers eight variants: the 466, 566, 666 and 766, each in standard and DT form. Power train work takes the biggest share of the book, from clutches, splitter, creeper and reverser through the bevel drive, final drives and PTO, backed by gear-path schematics. The hydraulic schematics show the lift pump, remote control valves and trailer brake valve, and the electrical section ends with a full wiring diagram. Set bevel drive backlash at 0.18 to 0.23 mm and hold main bearing clearance between 0.063 and 0.096 mm. Invented torque or pressure figures crack castings before harvest. Print the chapter, let it pick up grease on the bench, and have your tractor back in the field while the weather holds.
What's Inside This Fiat 466–766 Manual
| System | Pages | Key Topics |
|---|---|---|
| General | 3-10 | General Instructions, Safety Precautions, Spare Parts |
| Specification | 11-24 | Identification Data - Weights, Power Train - Brakes - Steering - Front Axle - Front Wheel Drive - Rear Wheels - Power Take-Off |
| Engine | 25-74 | Engine Block, Cylinder Head, Valve Gear, Crank Gear, Lubrication System, Cooling System, Performance Data |
| Power Train | 75-136 | Clutches, Transmission and Splitter, Creeper and Reverser, Bevel Drive and Differential, Brakes, Final Drives, Power Take-Off |
| Front Axle - Steering | 137-160 | Front Axle, Manual Steering, Power Steering, Steering Linkage |
| Front Wheel Drive | 161-182 | Front Axle, Drive Shafts, Axle Drive |
| Hydraulic Lift Unit | 183-228 | Lift, Lift Pump, Implement Attachment, Remote Control Valves, Trailer Brake Remote Control Valve |
| Electrical System | 229-246 | Charging System, Starters, Battery, Fuses, Lighting, Wiring Diagram |
| Service Tools | 247-252 | Engine Tools, Fuel System Tools, Power Train Tools, Hydraulic Lift Tools |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| PTO clutch control sleeve working clearance (LUK 11"/11") | 0.072 to 0.205 mm (0.0028 to 0.0080 in) | p. 75 |
| Plate thickness Transmission (LUK 11"/11", Models 466, 566) | 8.9 to 9.5 mm (0.350 to 0.374 in) | p. 75 |
| Main Bearing Clearance | 0.063 to 0.096 mm | p. 26 |
| Transmission Clutch Control Sleeve Working Clearance | 0.050 to 0.151 mm | p. 75 |
| Bevel Drive Backlash | 0.18 to 0.23 mm | p. 78 |
| Lift Relief Valve Crack-off Setting | 186 to 191 bar | p. 183 |
| Lift Pump Gear End Float | 0.090 to 0.160 mm | p. 185 |
| Alternator Voltage Setting (Bosch) | 13.7 to 14.5 V | p. 229 |
Fiat 466–766 Common Problems This Manual Covers
Fiat 666 hydraulic lift fails to hold load and relief valve cracks off with implement raised
Test the lift relief valve crack-off setting following page 183 and compare it against 186 to 191 bar. Check this before blaming anything else in the lift. Then work through the Hydraulic Lift fault chart for load-holding and erratic movement causes, so the implement stays up and you finish the field before rain.
Manual Section: Hydraulic Lift p. 183Hydraulic lift has insufficient lifting power or fails to operate when raising a mounted implement
Measure lift pump gear end float following page 185 and compare it against 0.090 to 0.160 mm. If it is out of range, put the pump on the bench before chasing anything else. Then verify the lift relief valve crack-off setting at 186 to 191 bar so the lift has full pressure for field work.
Manual Section: Hydraulic Lift Unit p. 185Power steering goes heavy, responds slowly, or snatches, with leakage at the control unit
Check the steering control unit for external leakage first, then work through the Power Steering fault chart in the Front Axle and Steering section starting page 137. Match your symptom (heavy, loose, slow, snatching, shimmy) to its listed cause before pulling parts. Inspect the steering linkage as well when the complaint is loose steering.
Manual Section: Power Steering p. 137Transmission and PTO clutch control sleeves out of working clearance with clutch disc plates worn thin
Measure transmission clutch control sleeve working clearance against 0.050 to 0.151 mm and PTO sleeve clearance against 0.072 to 0.205 mm, following page 76. Check disc plate thickness against the figure for your model and clutch make (LUK, VALEO or O.M.G.). On reassembly, torque clutch to flywheel capscrews to 25 Nm per page 84.
Manual Section: Power Train p. 76Engine shows insufficient compression on one or more cylinders during a compression test
Test compression on every cylinder following page 48 and compare readings across the block. A single low cylinder narrows the hunt. Check for faulty valves, worn piston rings and a blown cylinder head gasket, then fix it now rather than limping through harvest on a weak engine.
Manual Section: Engine Performance p. 48Trailer brake valve gives jerky braking or does not brake the trailer at all
Check the trailer brake remote control valve using the Trailer Brake Valve Trouble Shooting Chart on page 187. Verify whether the complaint is jerky braking or no braking at all, then test the valve against the listed causes before hauling a loaded trailer on the road again.
Manual Section: Trailer Brake Valve p. 187Frequently Asked Questions
What is the tightening torque for the cylinder head cap screws on the Fiat 466 and 566 tractors?
The tightening torque for the cylinder head cap screws (C1) on the Fiat 466 and 566 tractors is 147 Nm (15 kgm or 108 ft lb). p. 42
What is the normal valve clearance for the Fiat 466, 566, 666, and 766 engines?
The normal valve clearance for these engines is 0.25 mm (0.010 in) for the inlet valves and 0.35 mm (0.014 in) for the exhaust valves. p. 13
What is the correct oil pressure for the engine at governed speed on Fiat tractors?
The oil pressure for the engine when warm and at governed speed should be between 2.9 and 3.9 bar (3 to 4 kg/cm², 42.6 to 56.9 psi). p. 14
What is the specified belt tension for the fan, water pump, and alternator drive belt on Fiat tractors?
The belt should deflect by 10 to 15 mm (0.4 to 0.6 in) when a load of 108 to 127 N (11 to 13 kg, 24.3 to 28.4 lb) is applied to the belt section between the alternator and water pump pulley. p. 73
What is the correct tightening torque for the wheel shaft nut on the final drives for the Fiat 666 and 766?
The tightening torque for the wheel shaft nut (Cs) on the final drives for the Fiat 666 and 766 is 882 Nm (90 kgm or 651 ft lb). p. 83
Will this Fiat 466 Shop Manual download right away?
Immediate download of the complete 252-page searchable Shop Manual. Access it on any device, from a laptop at your desk to a phone in the field.
Does this Fiat 466 manual allow printing?
Yes. Print a chapter or just the pages for the job at hand, for use in your own shop. Any home or office printer works.
Reviews
There are no reviews yet.