Description

Komatsu PW100-3 Hydraulic Schematic – OEM Piping Diagrams for Blade Circuit

If you’re tracing a hydraulic leak or replacing a hose on a Komatsu PW100-3, the last thing you want is a misrouted line that causes a pressure drop or blows an O-ring. I’ve seen techs waste hours because they relied on a generic diagram or a photocopy from a previous job. This Komatsu PW100-3 Hydraulic Schematic is the factory document – 38 pages of piping layouts that show you exactly which tube goes where, which flange split to use, and which O-ring seals each connection. No aftermarket shortcuts, no reprints.

Hydraulic Piping (1/2) for Blade – Two Versions by Serial Number

This schematic breaks the blade circuit into two separate piping sheets based on your machine’s serial number range. Page 1 covers units from S/N 1601 to 2126, with detailed callouts for flanges, O-rings, tubes, and hoses. Page 2 starts at S/N 2127 and introduces a different tube part (20D-973-1371 instead of 1370) and an elbow fitting (07236-10315) that the earlier machines didn’t use. Trying to mix those up will cost you a return trip to the parts counter.

O-Ring and Flange Part Numbers: Why the OEM Schematic Matters

Every O-ring in the blade circuit is listed by Komatsu part number: 07002-12434 and 07000-13022 appear multiple times. The flanges are 07371-30500 split flanges. Aftermarket manuals often skip these details or list a generic “hydraulic seal” – that’s useless when you need the exact durometer and cross-section. This schematic gives you the factory spec for each connection, including spring washers (01602-20825) and bolts (01010-50830).

Does This Schematic Cover the Entire Hydraulic System?

Short answer: no. This manual focuses on the blade hydraulic piping – the circuit that controls the blade lift and tilt. It does not include the travel, swing, or attachment circuits. For those, you’ll need the full service manual. Pair this schematic with the Komatsu PW100-3 1995 Service Manual for engine and drivetrain specs. If you work on other Komatsu wheel loaders, the Komatsu Hanomag WA75-3 WA85-3 Parts Catalog is a good cross-reference for common hydraulic components.

3 Serial Number Ranges You Need to Check

The manual covers three distinct serial number breaks: 1601-2126 (page 1), 2127-2300 (page 2), and 1601-2300 (page 3 for the second half of the piping). Each range uses different tubes, hoses, and brackets. For example, machines after S/N 2127 get a revised tube (20D-973-1381) and a different hose (07096-00312). Check your machine’s serial plate before ordering parts – installing the wrong hose length can pinch the line under the cab.

Workshop Tip: Verify Part Numbers Against Your Machine’s Serial Number

Before you pull a hose, write down the serial number of your PW100-3. Open the schematic to the correct page for your range. Each part is listed with an “Options” column that shows which serial numbers it applies to. If you see “SN:1601–@”, that part fits all units in that range. If you see “SN:1601–2126”, it only fits up to that break. This level of detail is why OEM documentation beats any third-party diagram. Understanding Hydraulic systems fundamentals helps, but nothing beats the factory diagram for routing. Need to know engine basics? Check this Wikipedia article on diesel engines for general knowledge.

38 pages. That’s all you get – but it’s 38 pages of pure factory data. No fluff, no filler, just the piping diagrams and part numbers Komatsu issued to its dealers.

Frequently Asked Questions

Is this schematic compatible with the PW100-3 with a different attachment?

No, this manual specifically covers the blade circuit hydraulic piping only.

What should I do if my machine’s serial number is outside the ranges listed?

If your PW100-3 serial number falls outside the ranges shown in the manual (1601-2126, 2127-2300, or 1601-2300 depending on the page), you need the corresponding update sheet from Komatsu. The manual includes separate diagrams for each range. For serial numbers above 2301, you may need the later revision. Check the Komatsu PW100-3 Shop Manual 1995 for additional hydraulic schematics or contact a Komatsu dealer with your machine’s serial number to obtain the correct piping diagram. Using the wrong schematic can lead to using incorrect hose lengths or flange types, causing leaks or catastrophic failure. Do not guess – verify.

Stop guessing the plumbing on your PW100-3. Get the OEM Komatsu PW100-3 Hydraulic Schematic from AutoRepairManuals and keep it on your tablet or printed out next to the machine. Access the Factory Manual now and start working with the right routing the first time.