Description

Bomag BW 900 2003 Technical Manual

You’ve got a Bomag BW 900 2003 Technical Manual sitting on your workbench, and if you’re like me, you’ve already burned an afternoon chasing aftermarket spec sheets that left you guessing on charge pressure. That’s not how we work. This factory manual from 2003 is the real deal – 62 pages of OEM data straight from Bomag, a United Dominion Company. It covers the Honda GX620 engine, the hydrostatic travel drive, the vibratory system, and the water spray system. No fluff, no reprints, no third-party guesses. Just the numbers you need to get a BW 900 back on the job site.

Engine Specs and Service Limits

Page 4 lists the Honda GX620 K1 QAB: 2 cylinder, air-cooled, 20 hp at 3200 rpm. If you’re doing a valve adjustment or a full rebuild, you need the factory clearances. This manual gives you the performance numbers under ISO 9249 and SAE J1349 – that’s 20 hp ISO versus 18 hp SAE. Know the difference before you order parts. And the electric system is 12V, so don’t go throwing a 24V starter at it. Page 2 has the weights: 2497 lbs basic, 2924 lbs operating. That matters when you’re lifting the drum or pulling the engine.

Hydraulic System: Pump and Motor Data

Page 4 spells out the travel pump: axial piston model V013SIM00A03, 13 cm³/rev displacement, 280 bar high pressure, 22 bar charge pressure. Front travel motor is a Danfoss OMEW200, 198.2 cm³/rev. Rear travel motor is a Poclain MK04 radial piston, 408 cm³/rev – with the brake integrated. If you’re chasing a slow travel or weak charge, those numbers are your baseline. Aftermarket manuals often misprint charge pressure by 5-10 bar. You don’t want to cook a pump because you trusted a reprint.

Vibratory System Adjustments

Get the vibratory specs from page 3: hydrostatic drive, front drum only, frequency 4020 vpm (67 Hz), amplitude 0.020 in (0.5 mm), centrifugal force 3100 lbs (13.8 kN). That’s your target for eccentric weight adjustment. If the drum isn’t shaking right, check the charge pressure to the vibratory motor first – page 4 again. This manual also covers the water spray system (gravity feed, page 3). Don’t overcomplicate it; the specs are right there.

Brake and Steering System Checks

The service brake is SAHR (spring applied, hydraulic released) per page 3. Parking brake is hydro-mechanical. Steering is oscillating, articulating, hydrostatic – ±30 degrees steering, ±6 degrees oscillation. If you’re bleeding the steering circuit, you need the steering angle specs to set the stops. Page 3 gives you the radii: 65-inch inner track radius. Without that, you’ll set the stops wrong and chew up tires.

When to Trust Factory Data Over Aftermarket

I’ve seen aftermarket manuals call the BW 900 weight wrong by 200 lbs. That throws off transport calculations and steel deck loading. This is an OEM Bomag document – the same one their dealers use. Page 2 has the average axle load (1462 lbs) and static linear load (41.31 pli). That data came from the factory test stand. If you’re working on a rental fleet or a municipal yard, you don’t have time for bull. Use the factory numbers.

Related factory manuals you might need: Bomag MPH 454 Technical Manual – OEM Shop Data for Recycler/Stabilizer and Mag International T-MAG XC Mini Truck Owner’s Manual. Also check Bomag BC 670 RB Training Manual – Factory Specs & Repair Docs. For drivetrain basics, don’t confuse this with a Manual Transmission guide – that’s a different animal. But if you need torque converter or gearbox specs, the Manual Transmission data on Wikipedia is a decent primer.

Does this manual include torque specs for the drum mounting bolts?

Page 3 lists the vibratory system specs but does not explicitly give bolt torque values in the excerpt. The full 62-page PDF has a technical specifications section that should include fastener torques – refer to the hydraulic and engine sections.

Can I use this manual to rebuild the Honda GX620 engine?

This is a technical manual, not a full service manual, so it provides the engine performance data and basic specs (page 4) but not step-by-step disassembly. For a rebuild, you’ll want the Honda engine shop manual. However, the charge pressure and displacement numbers are critical for pairing the pump to the engine after a rebuild. Without those, you’ll set the hydraulic flow wrong and burn up the drum drive. The manual is 62 pages of targeted technical data – not a novel. Use it alongside the Honda manual.

If you’ve got a Bomag BW 900 in your bay and you need the factory numbers for charge pressure, engine output, or vibratory frequency, stop screwing around with photocopied spec sheets. Access the Factory Manual and get the job done right the first time.