International Harvester 420 All-Twine Baler Operator's Manual
This is the Operator's Manual for the International Harvester 420 All-Twine Baler. Spanning approximately 68 pages, this manual provides the complete setup, operation, maintenance, and troubleshooting guidance that IH issued to 420 baler owners and operators. Available as an instant digital download.
About the International Harvester 420 Baler
The International Harvester 420 was a conventional square baler produced during IH's highly regarded mid-century implement lineup, designed for the demands of commercial hay operations and general farm use. As an all-twine model, the 420 used double-knotting twine tie rather than wire, which reduced bale-handling hazards and was better suited to operations feeding bales directly to livestock. IH engineered the 420 with a reputation for heavy-duty pickup and plunger reliability, and the availability of optional equipment — including varied pickup and bale density configurations — made it adaptable to a wide range of crops and conditions. Today the 420 remains in active use on smaller hay operations and is a common subject of restoration among vintage IH collectors who appreciate the durability of its knotter and drive system design.
What This Manual Covers
This 68-page operator's manual moves systematically from initial setup through field operation, seasonal care, and fault diagnosis. Key sections include:
- Introduction — equipment overview, orientation conventions, and how to use the manual
- Work Safely — Follow These Rules — original IH safety guidelines for baler operation
- Preparing the Baler for Work (pp. 4–15) — hitch setup, PTO connection, pickup height, twine threading, bale chamber adjustment, and pre-season inspection procedures
- Operation of the Baler (pp. 15–20) — field operating procedures, bale density adjustment, twine tension, and proper windrow pickup technique
- Care of the Baler (pp. 21–40) — the manual's most extensive section, covering knotter service and adjustment, pickup maintenance, plunger and knife inspection, drive chain service, and all in-season maintenance procedures
- Storage — end-of-season preparation to protect the baler through the off-season
- Optional Equipment (pp. 42–44) — factory-documented options and how to install and operate them
- Troubleshooting (pp. 45–55) — fault diagnosis guide covering missed knots, broken twine, poor bale formation, and mechanical failures
- Lubrication & Lubrication Guide (pp. 56–58) — complete lubrication schedule with point-by-point guide
- Specifications — factory-spec dimensions, capacities, and settings
- Index (pp. 60–61) — subject and adjustment index for quick field reference
Why This Manual Matters
- Knotter service is the heart of this manual: The "Care of the Baler" section spans nearly 20 pages — far beyond a basic maintenance checklist. Knotter timing, billhook condition, and twine disc adjustment are documented with the factory's own specifications, which is exactly what's needed when a 420 starts tying inconsistently or missing knots altogether
- Dedicated troubleshooting section: With 11 pages of fault diagnosis, this manual goes well beyond generic guidance — the IH troubleshooting charts help isolate whether a knotting problem is mechanical, timing-related, or caused by twine quality and tension settings
- All-twine specific content: This manual covers the 420 in its all-twine configuration throughout — setup, threading, tension adjustment, and knotter service are all documented for twine tie operation, not wire
- Optional equipment documentation: Factory options are covered with their own installation and operating instructions, which is rarely available from aftermarket sources
- Original factory content: This is the manual IH issued to 420 baler owners, carrying manual code 1 084 995 R1
Manual Code: 1 084 995 R1