Quick checks before you begin
- Confirm the installed unit and retain bar/drum/position labels.
- Use the manual's removal and support procedure before bench work.
- Keep gears, shims and removed components in order, not in a mixed tray.
Preserve the evidence before stripping the bar
Record whether the reported problem affects one spindle, several positions on one bar, or several bars. These observations help scope the inspection but do not prove a single cause.
A bar that binds during shaft removal needs assessment before further force is applied. TM2109 notes that a bent bar may need straightening before shaft removal and warns that excessive vise pressure can damage the internal bore.
Inspect the related components
| Area | Inspect or preserve | Decision before ordering |
|---|---|---|
| Cam roller and follower | Flat spots, fit, measured wear and arm condition | Use the roller inspection separately from spindle-nut bushing checks. |
| Drive shaft, gears and bearings | Wear or damage; keep gear order and orientation | Confirm the exact shaft and pin design. TM2109 distinguishes older and newer shaft arrangements. |
| Drive gear tooth surfaces | Location and type of tooth damage | The manual distinguishes critical from non-critical areas. Do not replace every gear from a photograph of one small chip, or declare it safe without inspecting the specified area. |
| Journal, sleeve and seals | Measured fit, arm cracks, sleeve wear and O-ring condition | A scored appearance alone is not proof that the journal is unusable. Assess its fit using the manual. |
| Bore and retaining groove | Condition after cleaning and the correct gauge check | Do not size, ream or straighten without the specified setup and assessment. |
| Bottom bushing and shims | Condition and original shim arrangement | Retain the original records so reassembly decisions are not guesses. |
| Lubrication fitting and passages | Presence, condition and cleanliness | A missing or damaged fitting must be addressed; fitting a new spindle does not repair the lubrication path. |
Separate three outcomes in the parts list
Some parts have specific paired-replacement requirements. For example, the spindle-nut inner and outer bushings are replaced as a set and sized after installation in the TM2109 repair procedure. That does not mean every bearing, gear and roller on the bar must be replaced as a kit.
- Retain: components that meet the applicable checks and can be reused under the manual.
- Replace or repair: parts with confirmed damage or out-of-limit condition, identified by reference and installed position.
- Needs measurement: parts whose condition cannot yet be decided. Do not list these as confirmed failures.
Before the assembly returns to service
The repair is not complete when replacement parts have been fitted. The applicable manual also addresses retaining hardware, lubrication, assembly checks, run-in and installed bar leveling. These are separate workshop tasks with their own safety requirements.
Use the straightness and leveling guide to distinguish the measurements needed. Do not use powered run-in as a way to force tight components into service.
Pressing, bore sizing, straightening and powered run-in require the prescribed tools, fixtures and qualified personnel. This checklist is not the operating procedure for those tasks.
Technical basis for this article
The article paraphrases and organizes the sources below. It does not copy a service manual, and it does not replace the current documentation for the exact machine.
- TM2109 — PRO-12, PRO-12 VRS and PRO-16 Picking Unit Repair (20 July 2020), Section 40, Group 05John Deere Des Moines Works | repair manual
Bibliographic reference. Use the applicable manual for the installed unit. The purchased manual is not hosted on this website.
Questions buyers and technicians ask
Does a picker-bar overhaul mean replacing every component?
No. Record retain, confirmed replacement and needs-measurement decisions separately. Follow any paired-replacement requirements for the particular component.
Can all roll pins be treated as identical?
No. TM2109 identifies different shaft arrangements. Confirm the shaft version and its service parts before ordering.