Description

BISO 6170, 7070 Parts Catalog – What You Need on the Bench

Working on a BISO straw chopper without the right part numbers is how you end up with the wrong knife set or a V-belt that doesn’t track. I’ve seen guys order a clutch assembly for a 7070 when the machine had the W-version clutch, then spend half a day making phone calls. This is a BISO 6170, 7070 Parts Catalog – 37 pages of factory-original exploded views and part numbers. Not a reprint, not a scanned copy with blurred numbers. It’s the same document that shipped with the equipment. If you’re billing by the hour or farming by the season, guessing costs money. This catalog eliminates that.

The index starts on page 1 – you’ll see the section “TOOLS AND ACCESSORIES” and then the chopper breakdown. Every subassembly is listed with a part number like 4U.36.1 for knives, 4U.36.2 for the V-belt, and so on. Cross-referencing a worn part against the diagram means you order exactly what you need the first time. No returns, no down time waiting for the correct part to show up.

BISO 6170, 7070 Parts Catalog: What You Get on 37 Pages

37 pages isn’t a thick manual – it’s a focused parts book. That’s enough space to cover the basis frame (4U.36.51), the flail drum with bearing (4U.36.52), the distributor box (4U.36.54), and the electric regulation for the distributor box (4U.36.55). Each assembly gets its own exploded view with a parts list. You won’t find wiring diagrams or service procedures here – it’s a Parts Catalog, meant for ordering and identifying. And it does that job better than any third-party list ever could because these numbers come straight from BISO’s factory documentation.

If you need the service manual alongside this, check the BISO Straw Chopper Parts Catalog for the companion repair procedures. But for parts identification alone, this catalog holds everything.

Mounting Frame Differences: 6170 and 7070

The catalog separates the mounting frame for each model. For the 6170, it’s listed as “BISO-STRAW CHOPPER MOUNTING FRAME – 6170” (4U.36.56). The 7070 gets a different assembly: “BISO-STRAW CHOPPER LAYSHAFT SUPPORT – 7070” (4U.36.61) and “BISO-STRAW CHOPPER LAYSHAFT / CLUTCH – 7070” (4U.36.63). If you try to interchange these, the bolt holes won’t line up. The exploded view on page 2 shows the exact orientation of the layshaft support brackets. Buy the wrong one and you’re out the freight cost plus a restocking fee. I’d rather look at a diagram for five minutes.

Electrical Equipment and Clutch Versions

Two clutch versions are documented: the W-version (4U.36.65) and the S-version (4U.36.66). They are not interchangeable – the wiring harness differs. The catalog also covers the straw warning system (4U.36.68) and the general electrical equipment (4U.36.69). If you’re retrofitting a chopper onto a combine that didn’t have one from the factory, these pages tell you which electrical components to order. Compare that to aftermarket sources that lump everything under “BISO chopper parts”. This manual gives you the specific OEM part number.

Need to convert a belt-clutch setup? Three conversion kits are listed: 4U.36.70, 4U.36.71, and 4U.36.72. Each one has its own parts breakdown. Don’t assume the 6170 and 7070 use the same conversion hardware – the mounting bracket dimensions differ. Page 1 in the index shows exactly where each conversion kit falls in the catalog.

3 Conversion Kits and Chaff Spreaders Covered

The last section of the catalog covers chaff spreaders. You’ll find separate part numbers for the W-type spreader (4U.36.73 through 4U.36.76) and the heuling-type (4U.36.121). The spreader for the 6170 is listed at 4U.36.75. If you’re rebuilding a spreader drum, you need these numbers to source bearings and paddles. Without them, you’re measuring with a tape and praying.

OEM Documentation vs Aftermarket Parts Lists

I’ve dealt with aftermarket catalogs that re-number parts and leave out the supersession history. This is factory BISO documentation – what you see on the page is exactly what the manufacturer intended. That matters when you’re ordering a knife set for a flail drum that runs at 1500 RPM. The wrong hardness or thickness in a knife and you’ll throw a balance. Not guessing. Having the OEM part number means you get the correct geometry and metallurgy. For anyone working on farm equipment, Massey-Harris-Ferguson FF 30 GS 1957 Parts Catalog | OEM Fastener Guide and Futura FC200-FC400 Parts Catalog – OEM Wear Parts Specs follow the same philosophy: original prints, not summaries.

The Automotive Industry Overview might not talk about straw choppers, but the principle holds: original documentation is the baseline for safety and reliability. Don’t trust a third-party renumbering of critical parts. Automotive Industry Overview underscores why precise specifications matter.

Who Should Use This?

If you maintain a BISO 6170 or 7070 straw chopper on a farm or in a custom harvesting operation, this catalog belongs in your toolbox. Home garage enthusiasts who rebuild equipment as a side job will also find it useful – one part number lookup can save you a week of cross-shipping the wrong item. Beginners should pair this with the service manual to understand assembly order; the parts catalog only shows you what goes where, not how to put it together.

Access the Factory Manual now and stop ordering parts blind.

Does this catalog include torque specs or assembly instructions?

No.

How do I identify which clutch version my 7070 has?

Check the electrical connection style. The W-version (4U.36.65) uses a different magnet coil than the S-version (4U.36.66). The catalog provides exploded views of both – compare the coil housing shape to your machine. If you still can’t tell, call BISO dealer with the serial number. They’ll know.