Part of the New Holland Repair Manuals.
This is the factory service manual for the New Holland Boomer 40 and Boomer 50 compact tractors with cab, part number 48017703. It works through the tractor system by system and treats the hydrostatic drive as its own section rather than folding it into the transmission. The hydraulic section gives the figures that matter on the bench: an open-centre gear pump system with a stated capacity, the two relief settings, the lift capacity at the ball ends and the flow the pump must still make under load.
What's Inside This New Holland Boomer 40, Boomer 50 Manual
| System | Pages | Key Topics |
|---|---|---|
| Introduction and Standard Torques | 9-54 | How to Use the Manual, Shop Safety, Standard Tightening Torques, Approved Fluids, Model and Serial-Number Identification |
| Engine | 55-122 | Engine and Crankcase, Injection Pump Timing and Idle Regulation, Fuel System, Air Cleaner, Cooling System, Engine Overhaul |
| Clutch | 123-160 | Clutch and Its Release Mechanism, Pedal Free Play, Clutch Removal and Refitting |
| Transmission | 161-282 | Gear Transmission and Range Unit, Shift Controls, Transmission Strip-Down and Reassembly |
| Front Axle System | 283-390 | Driven Front Axle, Bevel Drive and Differential, Hub Reducers, Steering Knuckles, Axle Rebuild |
| Rear Axle System | 391-444 | Rear Bevel Gear Pair and Differential, Differential Lock, Final Drives, Bearing Preload and Backlash |
| Hydrostatic Drive | 445-544 | Hydrostatic Pump and Motor, Charge Circuit, Ground Drive Control and Linkage, HST Pressure Testing and Overhaul |
| Power Take-Off (PTO) | 545-628 | Rear and Mid PTO Clutch and Brake, PTO Solenoid and Its Supply From the Steering Pump, Speed Selection, PTO Overhaul |
| Brakes and Controls | 629-658 | Service Brakes, Parking Brake, Pedal Adjustment, Bleeding the Brake Circuit |
| Hydraulic Systems | 659-756 | Open-Centre Gear Pump System with Its Capacity and Reservoir, Two-Spool Valve Carrying the System Relief Valve, Safety and Main Relief Valves, Hydraulic Power Lift and Its Safety Relief, Flow Testing, Pump Overhaul |
| Hitches, Drawbars and Implement Couplings | 757-810 | Rear Three-Point Hitch and Lift Cylinder, Lift Capacity, Drawbars, Implement Coupling and Setting |
| Steering | 811-896 | Hydrostatic Steering Unit and Circuit, Steering Pump Which Also Feeds the PTO System, Steering Cylinder, Fault Finding |
| Wheels | 897-914 | Wheel and Tyre Fitment, Track Width Adjustment, Wheel Nut Torques |
| Cab Climate Control | 915-1078 | Heating, Ventilation and Air Conditioning, Compressor and Condenser, Refrigerant Handling, Charging and Leak Testing |
| Electrical Systems | 1079-1380 | Wiring Schematics and Harness Connector Views, Starting and Charging Circuits, Instruments and Lighting, Fuses and Relays, Circuit Test Procedures |
| Platform, Cab, Bodywork and Decals | 1381-1464 | Cab and Platform Assembly, Bodywork Panels, Hood and Grille, Glazing, Decals, Component Removal |
| Special Tool Index | 1465-1467 | Part Numbers of the Special Service Tools Each Procedure Calls for |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| All models | ||
| Hydraulic system type | Open centre, gear pump | |
| Minimum acceptable flow under load | 25 L/min (6.6 US gpm), which is 80 percent of the no-load rating | |
| Recommended hydraulic oil | NEW HOLLAND AMBRA MULTI G 134 HYD | |
| Boomer 40 / Boomer 50 | ||
| Pump flow at 2600 engine rpm | 31.2 l/min (8.2 US gpm) | |
| HST and gear models | ||
| Reservoir capacity | 43.0 l (11.4 US gal) | |
| Hydraulic system | ||
| System relief valve setting | 16671 kPa (2418 psi) | |
| Safety relief valve setting | 19609 kPa (2844 psi) | |
| Three-point hitch | ||
| Maximum lift capacity at the ball ends | 1250 kg (2756 lb) | |
| Lift cylinder | ||
| Diameter | 80 mm (3.15 in) | |
| PTO system | ||
| Oil supply | From the steering pump, through the PTO solenoid | |
New Holland Boomer 40, Boomer 50 Common Problems This Manual Covers
The hydraulics feel weak but the pump passes a flow test.
Test it under load, not just at idle. The pump should make 31.2 l/min at 2600 engine rpm with no load, and the manual sets the pass mark under load at 80 percent of that, which is 25 L/min (6.6 US gpm). A pump that gives full no-load flow and then collapses under pressure is worn internally. Check the system relief at 16671 kPa and the safety relief at 19609 kPa before you replace anything.
Manual Section: Hydraulic SystemsThe PTO will not engage, and the steering feels heavy too.
Treat them as one fault. The PTO system is supplied by the steering pump, with oil routed through the PTO solenoid, so a failing steering pump or a restriction in that supply starves both. Confirm the steering circuit first, then test the PTO solenoid and its circuit. Only when the supply is proven should you go into the PTO clutch and brake.
Manual Section: Power Take-Off (PTO)The three-point hitch will not lift a full load.
Check the numbers before you suspect the cylinder. Maximum lift capacity is 1250 kg (2756 lb) at the ball ends through an 80 mm lift cylinder, and the hydraulic power lift has its own safety relief valve in addition to the system relief at 16671 kPa. If the pump makes its flow and the reliefs are set correctly, the fault is in the lift itself or in the linkage geometry rather than in the supply.
Manual Section: Hitches, Drawbars and Implement CouplingsFrequently Asked Questions
Which tractors does this manual cover?
The Boomer 40 and Boomer 50 compact tractors in the 4WD cab specification, under part number 48017703. The specification pages list separate serial-number ranges for each model, so check your plate before following a procedure.
What flow should the hydraulic pump make?
31.2 l/min (8.2 US gpm) at 2600 engine rpm with no load. Under load it should still deliver at least 25 L/min (6.6 US gpm), which the manual defines as 80 percent of the no-load rating. A pump that meets the no-load figure but falls below 80 percent under load is worn even though it passes the first test.
What are the relief settings and the lift capacity?
The system relief valve is set to 16671 kPa (2418 psi) and the safety relief valve to 19609 kPa (2844 psi). The three-point hitch lifts a maximum of 1250 kg (2756 lb) at the ball ends, through an 80 mm (3.15 in) diameter lift cylinder. The reservoir holds 43.0 l (11.4 US gal) on both HST and gear models.
Where does the PTO get its oil?
From the steering pump, not the main pump. Oil flows from the steering pump through the PTO solenoid, which is worth knowing before you diagnose a PTO that will not engage: a steering complaint and a PTO complaint on the same tractor may share one cause.
How big is the manual and can I search it?
It is 1467 pages in English, a searchable and printable PDF. Search the text, print the pages you need for the bench, and keep the rest on a laptop in the workshop.
How quickly can I access this New Holland Boomer 40, Boomer 50 manual after?
You get a 1467-page searchable PDF (161 MB) that downloads instantly after checkout. Open it on your laptop, tablet, or phone, and bring it right to the shop floor.
Can I print this New Holland Boomer 40, Boomer 50 manual?
Yes. The PDF has no DRM restrictions, so print any page or section you need for your shop. Works with any standard printer.
