This is the David Brown Service Repair Manual covering the Cropmaster, 30C, 30D, 25, 25D and 900 tractors, 180 pages of factory workshop procedures for these vintage diesel, kerosene and gasoline machines.
It walks through the full drivetrain and running gear: diesel and petrol engine overhaul, clutch and gearbox, the rear axle with its brakes and reduction units, the hydraulic power lift and linkage, front axle and steering, the main frame, and the electrical system with battery testing. Torque figures, clearances and adjustment values are given throughout, including diesel valve clearance and hydraulic lift pressures.
With it you can diagnose a hard-starting engine, adjust the clutch, rebuild a tired gearbox, or restore a weak lift instead of guessing your way through a rebuild. Delivered as a downloadable PDF you can read on any device or print.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| Diesel Engine | 5-54 | Diesel, Ad4/25, Cad4/30, AD4/25H and CAD4/30H |
| Kerosene and Gasoline Engines | 55-80 | Kerosene Engine Service, Gasoline Engine Service, Fuel System, Carburetor |
| Clutch | 81-88 | To Adjust the Clutch Pedal |
| Gearbox and Differential | 89-100 | To Drain and Refill the Gearbox (Drain Hot Oil, i.e., After a Run., Drain Plug Is in the Centre of the Rear Axle on All Models, An Additional Plug Is Provided on the Detachable Pump Plate on the Bottom of the Gearbox Casing., Remove the Drain Plugs, And Allow to Drain for 10 to 15 Minutes, Then Replace the Plugs., Refill with 4 Gallons of Shell Tractor Oil 50. the Correct Level Is to the Top Mark of the Dipstick.) |
| Rear Axle, Brakes and Reduction Units | 101-112 | Rear Axle, To Adjust the Brakes, To Remove and Replace the Final Drive Shaft and Hub, To Remove and Replace the Final Drive Reduction Assemblies (Nearside Reduction Assembly) |
| Hydraulic System and Lift Linkage | 113-130 | Operation of Hydraulic Power Lift System, Exploded Components of the Hydraulic Pump, Arrangement of the Power Lift, Diagram of the Power Lift in the Lift Position |
| Main Frame and Fittings | 131-138 | Underside View of Main Frame, Top View of Main Frame, Main Frames, Main Frame Components, Lower Hitch Brackets, Seat and Mudguard Support |
| Front Axle and Steering | 139-146 | Front Axle Assembly, Mounting, Sectional Arrangement of Front Axle, Front Axle and Hub Components, To Remove and Replace the Front Axle Assembly |
| Electrical System | 147-180 | Batteries, To Test the Batteries, A Typical Battery Hydrometer, Specific Gravity Readings and Their Indications, Use of Heavy Discharge Meter, Batteries Out of Use |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| All Models | ||
| Control lever setting gauge clearance | 1/8" to 3/16" | p. 121 |
| By-pass valve control lever clearance | 1/8" to 3/16" | p. 121 |
| Diesel Engines | ||
| Cylinder head bolt torque | 90 lb. ft. | p. 6 |
| Fuel filter element replacement interval | Periodically | p. 39 |
| Oil filter element replacement interval, Diesel Engines | Every 360 operational hours | p. 22 |
| Injector opening pressure (new) | 185 atmospheres | p. 43 |
| Injector opening pressure (used) | 175 atmospheres | p. 43 |
| Kerosene and Gasoline Engines | ||
| Cylinder head bolt torque | 90 lb. ft. | p. 59 |
| Fuel filter gauze cleaning interval | Periodically | p. 78 |
| Oil filter element replacement interval (Kerosene and Gasoline Engines) | Every 360 operational hours (every six weeks) | p. 73 |
| 25-30 and 900 series tractors | ||
| Clutch pedal free movement | 1/16 in. (1.5 mm.) | p. 82 |
| Clutch pedal free travel (initial adjustment) | 1 in. (2.5 cm.) | p. 94 |
