- Safety first
- Disconnect battery negative terminal and remove ignition key; chock wheels and make sure PTO/engine cannot start while you work.
- Work with engine cold, wear gloves and eye protection, avoid loose clothing near rotating parts.
- If you’re uncomfortable with electrical testing or working under covers, get a tech to help.

- Reality check for an MF20 baler
- Many older Massey Ferguson MF20 balers and the small engines used on them are purely mechanical and may not have an electronic camshaft position sensor. Confirm whether the machine or its engine actually has a camshaft position sensor by checking the engine head/valve cover area for a small electronic sensor with a wire harness, or consult the engine/baler parts manual.
- If no sensor is present, the instructions below don’t apply — you’ll be dealing with mechanical timing/points instead.

- What the camshaft position sensor is and when it needs replacing
- What it is: a small electronic sensor mounted at the camshaft or timing cover that senses cam position (usually a Hall-effect or inductive type) and outputs a signal to the engine control/ignition.
- Symptoms that indicate replacement may be needed: engine won’t start or has intermittent starting, misfires, erratic idle, a diagnostic trouble code for cam/crank sensor, visible damage/corrosion to the sensor or connector, or failed electrical tests (open/short/no pulse).
- When to replace: replace the sensor if electrical tests fail, if it’s physically damaged, or if diagnostics point to it. If tests are good and wiring/connectors are bad, replace wiring/connector instead.

- Tools you need (basic tools plus why each is required) — detailed descriptions and how to use them
- Multimeter (digital, capable of DC volts and Ohms)
- Why: to test sensor resistance, check for signal voltage/pulses, check power and ground on the sensor connector.
- How to use: set to Ohms to measure resistance across sensor terminals when engine off; set to DC volts to check reference voltage (usually 5–12 V) with ignition on; with someone cranking the engine or using a scope substitute, backprobe signal wire to see pulses (DC volts switching) — observe safety when cranking.
- Basic socket set with ratchet and extensions (metric sizes 8–19 mm likely)
- Why: to remove covers, mounting bolts and sensor hold-down bolt.
- How to use: choose correct socket size, use extension or universal joint for awkward angles, pull bolts straight out after loosening.
- Combination wrenches (metric)
- Why: for bolts in tight spots where a socket won’t fit.
- How to use: fit the correct size, pull toward the wrench body to avoid rounding the head.
- Screwdrivers (flat and Phillips)
- Why: to remove small covers, clamps, or to gently pry connectors.
- How to use: use correct tip to avoid stripping screws; use small flat to push locking tabs on connectors.
- Small pick set or plastic trim tools
- Why: to release electrical connector tabs without breaking them.
- How to use: insert pick into tab, gently lift while pulling connector apart.
- Penetrating oil (e.g., PB Blaster)
- Why: to free seized bolts/mounts that may be corroded.
- How to use: spray on bolt threads, let soak 10–15 minutes before trying to break them loose.
- Wire brush and contact cleaner (electrical)
- Why: to clean corroded connectors and mounting surfaces.
- How to use: spray cleaner, brush gently, let dry before reconnecting.
- Dielectric grease
- Why: to protect electrical connections from moisture after you reinstall.
- How to use: small dab inside connector terminals (not inside sensor), plug together.
- Zip ties and rags
- Why: to secure wiring away from heat/rotating parts and clean oil/dirt.
- How to use: route wires away from moving parts and tie once in place; wipe areas clean before reassembly.
- Flashlight or work light
- Why: to see sensor location and wiring in tight/dirty areas.
- How to use: position to illuminate the work area; avoid leaving where it could fall into machinery.
- Optional but recommended: small digital oscilloscope or timing light with inductive pickup
- Why: to observe accurate pulse waveform from a Hall/inductive sensor — more definitive than a multimeter for pulses.
- How to use: clamp pickup or probe to signal wire and observe pulses while cranking/running.

- Steps to locate the camshaft position sensor (beginner-friendly)
- Visually inspect the engine around the cylinder head, valve cover, and timing cover for a small cylindrical or rectangular sensor with a 2–3 pin connector and a harness.
- Trace wiring from the engine control module (if present) or ignition coil back toward the head — the cam sensor is usually mounted where the cam passes by the timing cover or at the back/top of the head.
- If you can’t find it, consult the engine or baler parts diagram/manual or look up the engine model (sticker on the engine) and search its service manual.

- How to test the sensor and wiring (safe step-by-step)
- Visual check first: inspect connector and wiring for corrosion, broken wires, oil damage, or a loose fit. Clean and tighten connectors before further testing.
- Resistance test (for inductive sensors)
- Disconnect connector, set multimeter to Ohms, measure resistance across sensor terminals. Compare to specification from the engine manual. Typical inductive sensors can be a few hundred ohms; Hall sensors often show open circuit for resistance test (not conclusive).
- Voltage test (for Hall sensors)
- Reconnect sensor, turn ignition ON (do not start), backprobe power and ground pins: expect a reference voltage (often 5 V or 12 V) on the power pin and near 0 V on ground. If no reference, problem may be power supply or ECM.
- Signal test while cranking
- With the multimeter set to DC volts, backprobe the signal wire and have a helper crank the engine. You should see pulsed voltage (for Hall sensors switching between 0 and reference) or variable AC signal for inductive sensors. If no pulses, replace or further diagnose wiring/ECM.
- If available, use an oscilloscope or timing light to confirm a clean pulse waveform during cranking/running.

- How to remove the sensor
- Clean area around sensor to keep debris out of the engine.
- Disconnect the electrical connector by depressing the tab and pulling straight out; use a pick if needed.
- Remove the mounting bolt(s) with the correct socket or wrench; apply penetrating oil first if stuck.
- Gently twist and pull the sensor straight out; do not lever on it with metal tools that could break the sensor or damage the mounting boss.

- How to install a replacement sensor (if required)
- Match the replacement sensor exactly: same connector type, number of pins, mounting bolt spacing, sensor length and type (Hall vs inductive). Confirm OEM or equivalent by matching part number from the manual or supplier.
- If you can’t find an OEM number, bring the old sensor to a parts store to match connector and physical size — do not assume all sensors are interchangeable.
- Clean mounting hole and wipe mating surface free of debris and oil.
- Lightly apply dielectric grease to the connector terminals or use anti-seize on bolt threads if recommended (avoid grease on sensor face).
- Fit sensor straight in, tighten mounting bolt to a firm snugness. If you don’t have torque specs, tighten moderately — don’t overtighten (tighten until snug + small quarter-turn). Overtorquing the plastic housing will crack it.
- Reconnect the electrical connector, secure harness away from moving/ hot parts with zip ties.
- Reconnect battery and test by cranking and running; verify error codes are cleared (if ECM present) and operation is normal.

- What replacement part might be needed and how to source it
- Obtain the correct camshaft position sensor for the engine model, not generically for “MF20” without confirming engine model/part number.
- Look up the engine or baler parts manual, or contact an authorized Massey Ferguson dealer with chassis/serial numbers to get the exact OEM part number.
- Common alternatives: aftermarket Hall-effect cam sensors or inductive sensors that match OEM connector and mounting will work; ensure electrical specs match (reference voltage, pinout).
- If wiring or connector is corroded, you may need a pigtail or replacement harness connector — these are cheap and often necessary to restore signal.

- Final checks and tips
- After replacement, clear any stored fault codes if an ECU is present and verify symptoms are resolved.
- Keep old sensor until you confirm the repair success — it can be used to match for replacements.
- If testing shows good sensor output but the engine still malfunctions, suspect wiring harness, ECU/ignition module, or mechanical timing issues — that’s beyond a simple sensor swap and may require professional help.
- If unsure at any point, stop and consult a service manual or a qualified mechanic.

- Quick recap (no yapping)
- Confirm MF20 actually has a cam sensor, inspect visually, test with multimeter (power/ground/signal), replace only if tests or damage indicate failure, match exact sensor spec when buying, use basic hand tools, protect connectors with dielectric grease and secure wiring.
rteeqp73

Massey Ferguson 20 Bailer Knotter Servicing Part Two. Can We Make Hay With Old Farm Machines? Bailer knotters part two! further explanation of how it works. So all cleaned off and ready for re assembly. Almost!

Howard Big Baler and MF 590. Good quality Harvest in 2012, Howard Big Baler pulled by a MF 590. The baler is the first square baler.

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Tools & PPE
- PPE: safety glasses, gloves, steel-toe boots, hearing protection.
- Hand tools: metric/imperial socket & wrench set, breaker bar, ratchet, screwdrivers, punch set, soft (rawhide or rubber) mallet.
- Specialty tools: bearing puller / gear puller, snap‑ring pliers, hydraulic/bench press (or bearing driver set & heat source), seal driver / drift set, torque wrench, caliper or micrometer, dial indicator (for runout/endplay), shop crane or hoist (if removing heavy assemblies), container for oil/grease, rags, brake cleaner.
- Consumables: new input shaft (OEM part), replacement bearings, oil seals, circlips/snap rings, keys (Woodruff/key stock), gaskets, assembly grease, anti-seize/Loctite, clean gear oil for gearbox if applicable.

Safety precautions (must do before starting)
1. Park baler on level ground, block wheels and chock tires.
2. Disconnect tractor PTO driveline, remove PTO shaft and store away. Ensure tractor ignition off and keys removed.
3. Allow moving parts to come to rest; relieve stored energy (springs) in knotter/plunger systems if work nearby.
4. Remove all shields/guards only as required; keep track of guard fasteners.
5. Work with a partner for heavy components and use a hoist where needed.
6. Keep area clean and well lit. Dispose oils/grease properly.

Overview of procedure (high level)
- Remove belts/chains, shields, and components to access input shaft assembly.
- Unbolt bearing housings / gearbox cover, mark positions, remove gears/sprockets.
- Extract shaft, press off bearings/seals, fit new bearings/seals on new shaft, replace shaft into housing with correct shimming and endplay.
- Reassemble in reverse order, torque to spec, fill/replace lubricant, test at low speed.

Step-by-step replacement
1. Preparation
- Park, block, disconnect PTO and depressurize any systems. Clean area around gearbox/input housing to avoid contamination.
- Drain gearbox/oil sump if gearbox cover will be opened. Capture oil.

2. Document & mark
- Photograph and mark orientation of sprockets, gears, chains, shims, spacers, and timing marks. Label parts and fasteners by location.

3. Remove external drive components
- Remove drive belts, chains, sprockets, or pulleys on the input shaft. Use a puller on tightly fitted sprockets/gears. When using a puller, center it on the boss, use even pressure, and pull straight to avoid shaft damage.
- Remove any retaining nuts, washers, and keys. Keep keys/new keys ready.

4. Remove bearing housings / covers
- Unbolt bearing housings or gearbox cover to free the shaft. Support the shaft so it does not drop when the last bearing or support is removed.
- If the housing is sealed with gasket, carefully pry to avoid damaging machined surfaces.

5. Extract the input shaft
- With gears/sprockets removed, slide the input shaft out. If it’s stuck, use a bearing puller on the bearing/gear boss to pull evenly. Use penetrating oil on seized interfaces, but avoid heating nearby rubber seals.
- Support long shafts to prevent bending. Use a hoist or helper.

6. Disassembly on bench
- Secure shaft in a vise with soft jaws or in press. Remove snap rings with snap‑ring pliers.
- Use a hydraulic press or bearing puller to press bearings off the shaft. If bearings are tight and you don’t have a press, heat the bearing (bearing heater or oil bath ~80–100 °C) to expand—do not use an open flame. When pressing, apply force only to the bearing inner race when removing from shaft to avoid damaging bearing.
- Remove all seals, spacers, keys. Inspect gears for scoring and splines for wear.

7. Inspect components
- Inspect shaft for wear, fretting, pitting, straightness (use dial indicator), and spline damage. Measure journal diameters with micrometer. If shaft runout or damage exceeds OEM limits, replace shaft (preferred).
- Inspect housings and bearing bores for ovality, corrosion, and scoring. Replace housings or re-bore only with professional shop help.

8. Fit new bearings/seals to replacement shaft
- Clean shaft thoroughly. Install new bearings onto new shaft using a press or heating method:
- Heat the bearing uniformly (bearing heater or oil bath) to about 80–100 °C to expand, or use a press to push on the inner race.
- Use a bearing driver or block to drive the bearing squarely onto the shaft; apply force only to the inner race (for press-on bearings) to prevent ball/race damage.
- Install new seals with seal driver; tap evenly until flush with housing shoulder. Ensure sealing lips oriented correctly toward lubricant.
- Fit new keys and snap rings as removed originally. Replace any spacers in the original order.

9. Check and set endplay / shim stack
- Reinstall shaft into housing with bearings and housings lightly assembled. Measure axial play with dial indicator and compare to manual specification. Fit shims to achieve correct end‑play per MF20 manual (if manual unavailable, aim for minimal free endplay without preload—consult OEM spec before finalizing).
- Common approach: rotate and feel for smoothness; too tight = preload → risk bearing failure; too loose = excess endplay → gear misalignment.

10. Reassemble gears/sprockets and torque fasteners
- Reinstall gears/sprockets, using new keys where required. Use threadlocker where specified.
- Torque nuts/bolts to OEM specs. If you do not have the exact MF20 torque values at hand, consult the factory/service manual—torque wrench use is mandatory to avoid bearing preload or loosening.

11. Reinstall covers, fill gearbox
- Replace gaskets or use new RTV as recommended. Refill gearbox with specified oil to correct level.
- Reinstall all guards and reconnect PTO driveline.

12. Break-in & final checks
- Rotate shaft by hand to ensure smooth operation and correct engagement.
- Start tractor and run baler at slow speed (with no load) and listen for abnormal noise or heating. Re-check fasteners and leak points.
- After initial run-in (1–2 hours depending on usage), shut down and re‑torque critical fasteners and re-check oil level.

How the tools are used (brief practical notes)
- Puller/Gear puller: center jaws on gear boss, align forcing screw on shaft end; wind evenly. Use protective plate against shaft to avoid damage.
- Hydraulic/bench press: support shaft and use pressing plates to push on bearing inner race. Press slowly, keep shaft square. Use protective blocks if pressing on faces.
- Heat (bearing install): use bearing heater or oil bath; do not exceed 120 °C; do not use torch or direct flame. Heating expands bearing to slip onto shaft easily.
- Seal driver: place seal squarely over bore, tap evenly with mallet until seated flush. Avoid distorting seal lip.
- Snap‑ring pliers: compress or expand circlip gently and seat into groove without over-bending.

Replacement parts typically required
- New input shaft (if damaged or replacing); sometimes bearings are replaced without changing shaft if shaft good.
- Bearings (both sides where applicable) – replace rather than reuse.
- Oil seals.
- Snap rings / circlips, keys (Woodruff/key stock) and spacers/shims.
- Gaskets for gearbox cover.
- Gear/sprocket if teeth or splines are damaged.
- Lubricant (gear oil, grease) and threadlocker.

Common pitfalls & how to avoid them
- Reusing old seals/bearings: leads to premature failure — always replace.
- Incorrect bearing installation: applying force to the outer race when pressing on shaft will destroy bearing; always press on inner race for shaft-mounted bearings.
- Overheating bearings/seals with an open flame: destroys lubricant and metallurgy — use controlled heating.
- Incorrect endplay/shimming or excessive preload: causes noise and rapid bearing failure. Measure and set to OEM spec.
- Not marking gear/chain orientation: leads to timing/misalignment issues. Mark everything before disassembly.
- Contaminating bearings with dirt/solvent: keep components clean and use assembly lube.
- Not supporting shaft or heavy parts: causes bending or damage; use hoist/partner.
- Improper torque: overtightening can preload bearings; undertightening causes loosening. Use torque wrench and OEM values.
- Forgetting to replace woodruff key: worn key will let gear slip — always inspect and replace.

Testing & follow-up
- After reassembly run at low RPM unloaded, check for vibration, noise, leaks, temperature rise.
- Re-check torque after first few hours of operation.
- Inspect for oil leaks and re-check lubricant level.

Time estimate
- Depending on access and condition: 4–8 hours (single experienced tech) or longer if shaft/housings are seized or require machining.

Final note
- Always consult the Massey Ferguson MF20 service manual for exact torque specs, bearing endplay tolerances, and part numbers. Replacing bearings/seals is common; replacement of the shaft is required if journals, splines or threads are damaged beyond service limits.
rteeqp73

- Safety first
- Wear safety glasses, gloves, and steel-toe boots.
- Park baler on level ground, block wheels, disengage PTO, remove ignition key from tractor, and keep bystanders away.
- Use sturdy jack stands or blocks to support the baler if you must lift it — never rely on a hydraulic jack alone.

- What “differential service” means here
- Check and change gearbox/differential oil.
- Inspect for leaks, metal debris, and seal/bearing wear.
- Replace leaking seals, crushed drain/fill washers, or damaged bearings/gears as required.
- Note: setting ring-and-pinion backlash and bearing preload is precision work; if needed, you may want a shop or a replacement differential assembly.

- Tools you probably already have (basic tools) — what each tool is and how to use it
- Socket set with ratchet and extensions
- Description: range of sockets (metric/imperial) and a 3/8" or 1/2" ratchet.
- How to use: choose correct-size socket, fit on fastener squarely, pull handle to break loose, then spin ratchet. Use extension to reach recessed plugs/bolts.
- Open/box-end wrenches
- Description: fixed-size wrenches for nuts and bolts.
- How to use: place wrench fully over the nut, pull toward you; use correct size to avoid rounding heads.
- Screwdrivers (flat and Phillips)
- Description: common driver types for clamps, covers, small screws.
- How to use: pick correct tip, hold firmly, turn slowly to avoid stripping.
- Drain pan
- Description: shallow pan to catch oil.
- How to use: place under drain plug to collect old oil cleanly.
- Clean rags and parts solvent (brake cleaner or mild degreaser)
- Description: for cleaning mating faces and wiping oil/metal debris.
- How to use: spray solvent, wipe with rag, avoid breathing fumes.
- Funnel or small hand pump
- Description: funnel for pouring new oil or hand pump for filling small ports.
- How to use: use funnel or pump to add oil without spilling.
- Wire brush
- Description: small steel brush.
- How to use: remove rust and dirt from mating surfaces and bolt threads.
- Pliers (slip-joint, needle-nose)
- Description: gripping and removing clips or cotter pins.
- How to use: grip firmly and pull straight out for cotter pins or clips.
- Hammer and soft mallet (rubber or dead-blow)
- Description: for light persuasion of parts.
- How to use: use soft mallet to avoid damaging surfaces; use hammer with punch only if necessary.
- Oil-resistant gloves
- Description: protect hands from oil and grime.
- How to use: wear during all fluid and dirty tasks.

- Additional tools that are strongly recommended (why required)
- Torque wrench
- Why: ensures bolts and pinch nuts are tightened to correct torque to avoid loosening or overtightening.
- Use: set required torque and tighten until wrench clicks; consult manual for values or use factory specs.
- Seal puller / flat-blade seal remover
- Why: removes old oil seals without damaging housing.
- Use: hook behind seal lip and pry straight out.
- Seal driver or socket set sized to seal OD
- Why: to install new seals squarely without damage.
- Use: place new seal flush to housing and tap evenly with driver or socket until seated.
- Torque socket or breaker bar (for stubborn bolts)
- Why: older bolts can be very tight; breaker bar gives extra leverage.
- Use: apply steady pressure; avoid sudden jerks.
- Bearing puller and press or hydraulic press (if bearings need replacing)
- Why: bearings and races are pressed on; puller/press removes and installs them safely. Trying to hammer bearings often damages the housing.
- Use: puller grips bearing for extraction; press pushes new bearing evenly onto shaft or into housing.
- Dial indicator with magnetic base (for checking backlash)
- Why: measuring ring-and-pinion backlash requires precision to avoid premature gear failure.
- Use: mount indicator, rotate ring gear, measure peak-to-peak movement; adjust with shims until spec met.
- Micrometer / calipers and shim kit
- Why: checking pinion depth and selecting correct shims for preload/backlash.
- Use: measure and change shims incrementally to reach specifications.
- Impact driver (optional)
- Why: can remove stuck screws/bolts quickly.
- Use: set bit and strike with hammer or use powered mode if rated.

- Consumables and replacement parts you should have on hand
- Gear oil (recommended: SAE 80W-90 or manufacturer-specified gear oil GL-4/GL-5)
- Why: differential/gearbox lubrication. Use the viscosity and spec in the baler manual if available.
- New drain and filler plug crush washers or copper washers
- Why: prevent leaks at plug mating surfaces.
- New oil seals for output shafts/axles
- Why: seals commonly fail and cause leaks; replace any that are weeping or old/crumbled.
- Gasket or RTV sealant (if differential cover has a gasket)
- Why: to reseal cover and prevent leaks.
- Replacement bearings (if noisy or have play)
- Why: worn bearings cause noise, heat, and gear misalignment.
- Replacement ring-and-pinion (only if teeth are chipped, scored, or show heavy wear)
- Why: damaged gears cause poor performance and rapid failure.
- Clean rags, gasket scraper, thread locker (Loctite), anti-seize (optional)
- Why: clean mating surfaces, secure bolts, prevent galling.

- Step-by-step service procedure (beginner-friendly)
- Prepare and access differential/gearbox
- Park on level ground, block wheels, disengage PTO, and ensure baler is stable on stands/blocks.
- Locate differential/gearbox housing — usually under baler near main drive. Clean the area so dirt doesn’t fall into openings when plugs are removed.
- Check oil level before draining
- Wipe filler plug area, remove filler plug first (upper plug); if oil is up to the fill hole or slightly below, level is OK. If unsure, proceed to change.
- How to use tools: socket or wrench on filler plug; open slowly to relieve pressure.
- Drain old oil
- Place drain pan under drain plug, loosen and remove drain plug with socket/wrench.
- Let oil drain completely. Inspect oil for metal flakes/strong metallic smell.
- How to use tools: remove plug and let gravity drain into pan; use rags to wipe off sludge.
- Inspect the drained oil and magnet
- Look for metal particles (fine powder vs. chunks). Fine metal is normal to some degree; large shards indicate gear or bearing damage.
- If there is a magnetic plug, remove and inspect the magnet for heavy deposits.
- Clean drain and filler plug threads and replace crush washers
- Clean threads with wire brush, fit new washer on plug, and reinstall drain plug hand-tight then snug to spec (use torque wrench if available).
- How to use tools: ensure threads are clean; torque wrench if you know spec, otherwise tight + a small quarter turn—do not overtighten.
- Access and inspect seals/shaft ends
- Wipe around output shaft seals; run your finger around to check for oil seepage.
- If leaking, remove seal using seal puller or flat screwdriver carefully.
- How to use tools: slide puller behind lip and pry out; for stubborn seals, a small chisel can be used carefully.
- Replace seals if leaking
- Clean housing bore, apply light oil to new seal lip, seat new seal with seal driver/socket until flush.
- How to use tools: align seal squarely, tap evenly with soft mallet until seated.
- Refill with fresh gear oil
- Use recommended gear oil. Fill via filler hole until oil level is at the bottom of the filler hole.
- How to use tools: funnel or hand pump to pour without spilling. Wipe any spills.
- Final checks and run test
- Reinstall filler plug with new washer, torque to spec if known.
- Re-engage baler at low speed and listen for unusual noises; check for leaks at seals, drain plug, and housing.
- After a short run, re-check oil level and top up if necessary.

- When you should replace parts and why
- Oil seals
- Why replace: seals harden and crack with age causing visible leaks and oil loss.
- Replacement: inexpensive and straightforward for a beginner.
- Drain/fill plug washers and gaskets
- Why replace: old washers leak; gaskets may be compressed and leak after removal.
- Replacement: low cost; always replace when servicing.
- Bearings
- Why replace: if you detect noise (grinding, rumbling), excessive play on shafts, overheating, or metal debris indicating bearing failure.
- Replacement difficulty: intermediate to advanced — requires bearing puller/press and measurement for preload/shims. If you lack tools, replace the whole differential housing or seek a machine shop.
- Ring-and-pinion gears
- Why replace: chipped, broken, or heavily scored teeth cause poor operation and will ruin bearings and other components.
- Replacement difficulty: advanced — requires measuring backlash, pinion depth, and using shims; professional setup recommended.
- Bolts/fasteners
- Why replace: rusted or stretched bolts can fail; always replace any damaged bolts and use thread locker where appropriate.

- If you encounter bearing or gear damage — two options
- Replace the entire differential/gearbox assembly (recommended for beginners)
- Why: avoids complex shim/backlash setup and special tools; usually faster and safer.
- How to use basic tools: unbolt assembly, swap with replacement, install with new gaskets/seals, refill oil.
- Repair in-place or rebuild (requires shop or advanced tools)
- Why: cheaper if you have required tools and experience.
- What you need: bearing puller/press, dial indicator, shim kit, torque wrench, service manual specifications.
- If you attempt: take lots of photos during disassembly, keep parts in order, and only perform if you can measure and set backlash and preload correctly.

- Tips and common beginner mistakes to avoid
- Don’t overtighten drain/filler plugs — you can strip threads in cast housings.
- Always remove filler plug before drain plug to ensure oil will refill properly after draining.
- If you see large metal chunks, stop and consider professional help — continuing to run may cause catastrophic failure.
- Keep dirt out: clean around plugs and opening before opening the gearbox.
- If you lack tools to set backlash or press bearings, opt for a replacement assembly or shop rebuild.

- Quick checklist to finish job
- New oil installed to proper level.
- All plugs sealed with new washers and tightened.
- Seals replaced where leaking.
- No visible leaks after short run.
- Abnormal noises addressed: if still present, inspect bearings/gears or consult shop.

- Recommended parts to order before starting (typical beginners’ kit)
- Correct-spec gear oil (SAE 80W-90 GL-4/GL-5 or manual-specified).
- Drain and fill plug washers (copper or crush type).
- Output shaft oil seals sized to your baler differential.
- Small bottle of RTV gasket maker or replacement gasket if applicable.
- Replacement bolts or fasteners if any are corroded.
- Optional: replacement differential assembly (if you prefer swap-out instead of internal rebuild).

No extra questions.
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