Description

Bomag BW 100 AD, BW 100 AC, BW 120 AD, BW 120 AC 2004 Training Manual

You are trying to get a Bomag roller back in the dirt after a travel system failure, but the charge pressure feels off and you have no spec to confirm. Guesswork on a hydraulic charge relief valve costs you a day of downtime and a hundred bucks in wrong parts. That is exactly why this 2004 Bomag Training Manual for the Bomag BW 100 AD, BW 100 AC, BW 120 AD, BW 120 AC belongs on your bench, not buried in a file cabinet.

This is not a reprint of an operator booklet or a third-party summary. These 107 pages are the actual service training document used by Bomag techs to learn the Series 4 machines. Inside you get factory procedures for the Kubota diesel engine, the hydrostatic travel system, the vibration circuit, steering, and the full electric system with wiring diagrams. Every test and adjustment is explained in the sequence a trained service engineer would follow.

Engine Section Coverage: Kubota Diesel and Valve Clearance

Section C kicks off with the Kubota diesel engine – component views, pump installation on the engine, and flywheel-side layout. The real meat is on page C6: adjusting the valve clearance. The manual tells you the exact feeler gauge thickness and the order to turn the crankshaft. If you have ever had a valve train noise after a head rebuild because you guessed the clearance, you know why this spec matters. The trouble shooting on page C8 covers hard starting, low power, and smoke conditions. You get a flow chart approach, not a generic “check fuel” line.

Does This Manual Cover the Travel System?

Yes, and it goes deeper than most aftermarket hydraulic guides. Section D walks through the travel pump, travel pump control, charge pressure relief valve (page D9), and high pressure relief valves (page D10). The drum drive motor and wheel drive motors on AC machines get their own pages. When the machine creeps with the travel lever in neutral, the manual gives you a dedicated diagnosis on page D30. The charge pressure spec is listed in the control section – no need to hunt through a separate hydraulics book. The hydraulic circuit diagrams are referenced in the electric section G, but the actual pressure values are printed right in D7 and D9.

7 Systems Broken Down – What You Get

The manual splits the machine into seven main function groups: General (safety, fluid specs), Maintenance schedules, Kubota engine, Travel system, Vibration system, Steering, and Electric circuit diagrams. Each group begins with a component list and ends with specific troubleshooting. The vibration section (E) covers the vibration pump, control valve, and motor. If the roller does not vibrate or vibrates at the wrong frequency, the fault tree on page E6 walks you through the pressure checks and electrical continuity tests. The electric diagrams in section G include component lists, relay cross references, and potential cross references so you can trace a short without guessing which connector is which.

Adjusting Valve Clearance: Page C6 Specs

For the Kubota engine, the valve clearance adjustment procedure on page C6 is the one you need to follow to the letter. The manual specifies the clearance value for intake and exhaust, the rotation direction, and the firing order. If you try to adjust a cold engine with a hot spec or vice versa, you risk burning a valve. The training manual flags that. It also shows the location of the timing marks and the locknut torque. This is not a generic engine manual – it is written specifically for the engine variant installed in these Bomag rollers.

Why Factory Training Manual Beats Aftermarket

Aftermarket hydraulic diagrams for construction equipment are often redrawn from photos and missing component numbers. This Bomag manual uses the exact part numbers from the factory spare parts catalogue (referenced in the foreword). The wiring diagrams are original Bomag prints with function groups and relay cross references. You can match the wire colors to the harness on your machine without second-guessing. If you need a different factory document for another compactor, check the Bomag BC 670 RB Training Manual – Factory Specs & Repair Docs or the Bomag BW 24 R 2001 Training Manual – Factory Specs & Repair. For a larger tandem roller, the Bomag BC 771 RB 1999 Training Manual – Real Workshop Specs is also available. Outside of Bomag, understanding the hydraulic drive principle is similar to a Manual Transmission in basic mechanical layout, but the hydrostatic control is different. For older machines with mechanical drive, see how a Manual Transmission is serviced.

FAQ

Is this manual suitable for a beginner working on a Bomag roller?

Not if you have never held a wrench. It assumes you know basic engine and hydraulic theory.

Does it include wiring diagrams?

Yes, section G has the full electric circuit diagrams for the Series 4 machines. That includes function groups G1-G6, relay cross references, and potential cross references for tracing shorts. The diagrams are original Bomag prints, not redrawn. They show the wire colors, connector pin numbers, and component locations. If you are chasing an electrical fault on a BW 120 AD-4, you can find the exact circuit for the vibration control or the travel lever switch. The manual also includes a list of components on page G5 with their designations. You will not need a separate wiring diagram book.

What models are covered exactly?

Bomag BW 100 AD, BW 100 AC, BW 120 AD, and BW 120 AC – all Series 4 from 2004. The AD models are smooth drum, the AC models have a wheel drive on the rear.

Does the manual give torque specs for the hydraulic fittings?

It gives adjustment specs for pressure relief valves and valve clearances, but torque values for fittings are in the repair instructions referenced in the foreword. This is a training manual, not a full repair manual, so it focuses on diagnostics and adjustments.

You have the machine sidelined and the rental line is calling. Stop burning time on generic procedures. Access the Factory Manual now and get the exact specs for your Bomag BW 100 or BW 120 Series 4 roller – valve clearance on page C6, charge pressure on D9, and full wiring in section G.