Description

Bobcat 325, 328, 331 2006 Service Manual

I’ve torqued more head bolts than I’ve had hot meals, and let me tell you – the difference between a job done right and a cobbled-together fix is always in the manual. Not some aftermarket knock-off that guesses at specs, but the real OEM print. This Bobcat 325, 328, 331 2006 Service Manual is exactly that: 798 pages of factory-directed procedures, torque values, and safety protocols that keep you from turning a routine repair into a trip to the ER. Skip a step here, guess a pressure there, and you’re either wasting time or wrecking parts. I don’t have patience for either.

Safety and Maintenance: Lifting and Blocking the Excavator

Before you pull a single wrench, read the Lifting and Blocking procedure in this manual. The factory tells you exactly where to place the cribbing, how to engage the swing lock, and when to lower the blade. These instructions are not optional. I’ve seen a 331 tip because a guy thought he could improvise. Page references for block placement are in the Safety and Maintenance chapter – trust me, follow them. The manual also covers tailgate adjustments for early and later models, so you don’t bust a hinge trying to get to the battery.

Bobcat 325, 328, 331 Service Manual: Engine Lubrication System Procedures

Oil change intervals are listed in the Service Schedule chart. But the real value is in the detailed steps for checking oil level, replacement procedures, and filter specs. The manual specifies the correct viscosity and capacity – don’t rely on a quick Google search. For the 2006 D Series, the engine serial number location is shown so you verify you’re looking at the right unit. If you’re working on a 325 or 328, the same procedures apply, but cross-reference the serial number ranges in the front of the document.

Main Relief Valves: Testing and Adjusting

This is where most aftermarket manuals fail. They give you a single pressure number and call it done. This OEM manual splits the procedure by serial number breakpoints – below and above certain ranges. You get specific instructions for the main relief valves, port relief valves, and crossport relief valves. The System Pressures at Gauge Port Specifications section is your go-to. Do not touch the valve stack without those numbers. I’ve watched a guy overshoot a port relief by 50 psi and blow a seal – cost him half a day and a new cylinder.

Does This Manual Cover the Fuel System?

Yes, and it does it right. The Fuel System chapter includes fuel specification, filling, filter replacement, water removal, and air bleed procedures. For a diesel engine, air in the lines means no start – the manual walks you through the prime sequence with exact bleed screw locations. Draining the tank is covered too, with safety warnings about fire and static discharge. If you’re swapping a fuel filter on a 331, the manual shows the correct orientation and torque for the filter housing. No guessing.

Hydraulic/Hydrostatic Schematics – What You Get

The Hydraulic System section contains full schematics, a glossary of symbols, and a troubleshooting chart. For a machine with boom, arm, offset, bucket, and blade cylinders, plus travel motors and control valves, you need the real schematic to trace pressure drops. The manual also covers the case drain filter and diagnostic couplers – often overlooked but critical for contamination control. If you’ve worked on a Manual Transmission, you know that a blocked passage can mimic a bad pump – same logic here. The schematic saves you from replacing parts that are fine.

Swing Lock Operation – Understand Before You Touch

The swing lock is a safety device, not a convenience feature. This manual explains its operation, how to engage it, and what to check if it sticks. Ignore this and you risk the upper structure swinging unexpectedly while you’re under the machine. The Manual Transmission analogy again – if the detent ball is worn, you get false neutrals. The swing lock has a similar engagement mechanism; the manual shows you how to inspect it.

Related Manuals for Cross-Reference

• Bobcat 325 328 2007 Service Manual
• Bobcat 325 328 2008 Service Manual
• Bobcat 325 328 1998 Service Manual

FAQ

Is this the OEM manual or a reprint?

This is the original factory PDF from Bobcat, not a third-party copy or reprint.

What serial numbers does it cover?

From the OCR: covers 325 S/N 232511001 & Above, 328 S/N 232411001 & Above, and 331 (D Series). For exact serial breakpoints on specific hydraulic procedures, refer to the manual’s serial number location section.

Can I find torque specs for the hydraulic fittings?

Yes. The manual lists system pressures at gauge ports and includes torque values for hydraulic components in the cylinder disassembly/assembly procedures. However, not every bolt is listed – you’ll need to consult the specific section for the component you’re working on. For example, the boom cylinder assembly gives torque for the rod gland and piston nut.

Does this manual cover the engine overhaul?

It covers engine lubrication, cooling, fuel, and air cleaner service – but not a full engine teardown. The focus is on the excavator-specific systems. For engine internal work, you’d need the engine manufacturer’s service manual. This Bobcat manual gives you the installation and adjustment procedures relevant to the machine, like mounting, belts, and exhaust.

That’s the straight story. 798 pages of factory-sourced information with safety warnings that could save your fingers, your wallet, and your machine. I don’t sell anything I wouldn’t use myself on a job. If you’re serious about keeping a 325, 328, or 331 running right, access the factory manual.