Komatsu JMHB660H-2 Attachment Shop Manual (SEN06977-09)

This Komatsu JMHB660H-2 Attachment is a hydraulic breaker you hang off an excavator to bust rock, concrete, and stubborn trench work. The Komatsu JMHB660H-2 Attachment Shop Manual (SEN06977-09) is what techs and shop guys reach for when the hammer’s weak, dead, or leaking and downtime is burning money. People usually want this kind of manual to get from “it’s not hitting right” to “back breaking rock” without a lot of guesswork or parts roulette.

What this manual helps you do

• Trace hydraulic issues on the breaker side, so you can tell if the problem is in the hammer or the carrier.
• Check wear parts and seals, and decide if you can get by with a reseal or need deeper component work.
• Follow teardown and reassembly sequences for the hammer body, using normal workshop tools plus the usual lifting gear.
• Diagnose performance problems like weak blows, slow cycling, or overheating using the tests these manuals usually outline.
• Verify correct installation setup on the attachment so you’re not chasing a “fault” that’s really a mounting or hose routing issue.

Who this is for

This is aimed at field techs, shop mechanics, and fleet maintenance folks who actually wrench on hydraulic breakers. If you’re just looking for basic operating tips or safety decals, you’re better off with the operation/installation manual, not this shop manual.

FAQ

Q: Is this a PDF I can download and search?

A: Yes, it’s a PDF you can download, search by keyword, and print the pages you want for the toolbox.

Q: Does it go into real repair work, or just light maintenance?

A: The Komatsu JMHB660H-2 Attachment Shop Manual walks through workshop-level repair, disassembly, inspection, and reassembly procedures for the hammer.

Q: How do I know if it matches my exact hammer version?

A: You’ll want to match JMHB660H-2 and the book number SEN06977-09 to the ID plate and paperwork on your attachment; if your tag shows a different model code, you need the matching manual for that code.

Bottom line: if you’re the one expected to fix a JMHB660H-2 in the field or shop, this is the right manual; if you only operate the machine and don’t turn wrenches, you can skip it.

Table of Contents:

Table of contents not available.

Komatsu