Summary and tools
- Goal: systematically find why the MF35 engine won’t start, runs poorly, smokes, overheats, or loses power.
- Tools: multimeter (0–20 V DC), 12 V/6 V battery tester or charger (match system), adjustable wrench set, screwdrivers, spark plug socket (if petrol), compression tester (screw-in), fuel pressure/bleeder kit (diesel useful), timing light (petrol), vacuum gauge (optional), oil pressure gauge (optional), small mirror, torch, rags, drain pan, protective gloves/eye protection, torque wrench, wire brush, carburettor cleaner, penetrating oil.
- Safety: work with engine off, key out, battery disconnected when doing wiring. Beware moving parts, hot surfaces, fuel vapour. Ventilate when running.

Quick orientation — how the MF35 engine works (simple theory)
Think of the engine as three basic systems that must cooperate: air in, fuel + ignition, and exhaust — all coordinated by compression and timing. Analogy: engine = a set of small controlled explosions that push pistons; pistons drive the crank which drives the tractor. For the explosion to be right you need the right air/fuel mix (fuel system + air filter), proper compression (mechanical integrity of pistons, rings, valves, head gasket), and correct ignition/injection timing (spark or fuel injection timing). The charging/starting systems supply electricity to start and keep electrical systems working. Cooling and lubrication keep the engine from overheating or wearing out.

Common MF35 variants and what that implies
- MF35 came in petrol and diesel (and gas) variants. Procedures overlap but ignition vs injection differs:
- Petrol: spark plugs, coil/distributor or points, carburettor.
- Diesel: fuel lift pump, injection pump and injectors; no spark system.
- Also older MF35s often have 6 V electrical systems; many have been converted to 12 V. Verify system voltage before electrical tests.

Step-by-step diagnostic flow (beginner-friendly). Follow this order — each step rules out a major class of problems.

1) Visual & basic checks (5–10 minutes)
What to look at
- Fuel level and smell, fuel leaks.
- Battery condition (clean terminals, secure), corrosion, loose cables.
- Belts (fan/alternator): cracks, slack.
- Hoses: cracks, swelling, coolant leaks.
- Air filter: clogged element or oil-soaked.
- Oil level and coolant level.
Why: many failures are simple — empty tank, dead battery, clogged filter. Analogy: like checking petrol, oil, and tires before a car trip.

2) Battery and starting system (if engine won’t crank or cranks slow)
Components and theory
- Battery: supplies cranking current. If weak, starter won’t spin fast enough for compression & ignition to work.
- Starter motor & solenoid: convert electrical energy to mechanical turning.
- Cables/ground: must carry high current.
- Ignition switch, starter button/solenoid control.
Diagnostic steps
- Confirm system voltage: measure battery at rest. For 12 V system: ~12.6–12.8 V is fully charged. For 6 V: ~6.3 V. If much lower, charge or replace battery.
- Cranking voltage: while cranking, voltage should not collapse below ~9–10 V for 12 V systems (or ~4.5–5 V for 6 V). If it drops very low, battery or high resistance in cables.
- Visual: clean terminals, tighten clamps, inspect positive cable to starter and ground strap to block.
- Starter draw test: use amp clamp if available; high draw with no rotation = starter fault; low draw and no spin = bad connection.
Common faults and fixes
- Corroded/loose terminals — clean and tighten.
- Bad battery — recharge or replace.
- Loose ground strap — clean & secure.
- Worn brushes or armature in starter — rebuild/replace.

3) Charging system (engine runs but battery dies)
Components and theory
- Dynamo/generator (alternator on conversions) + voltage regulator produce current to run lights and recharge battery.
- If charging fails, battery discharges and electrical performance degrades.
Diagnostic steps
- Measure battery voltage with engine off and then running:
- For 12 V: off ~12.6 V; running idle ~13.8–14.8 V if charging correctly.
- For 6 V: off ~6.3 V; running ~7.2–7.8 V.
- If voltage is below charging range at operating RPM, suspect dynamo/regulator/drive belt.
- Check wiring, brushes, commutator (dynamo) or diodes/brushes (alternator).
Common faults and fixes
- Loose drive belt — tighten/replace.
- Worn brushes or faulty regulator — replace regulator/brushes.
- Bad diodes in alternator — replace alternator.

4) Air intake and filters (hard starting, poor power)
Components and theory
- Air filter cleans incoming air. Restricted air produces rich mixture, hard starting, black smoke.
- Carburettor (petrol) meters fuel and air. Vacuum leaks upset mixture.
Diagnostic steps
- Inspect air filter: if paper/oiled element is clogged, replace.
- For petrol: remove air box and crank the engine (careful—do not run long without filter) to see improvement.
- Check for vacuum leaks at carburettor manifold: spray carb cleaner around joint while engine idling — sudden RPM change indicates leak.
Common faults and fixes
- Dirty/soiled filter — replace.
- Air leaks at manifold gaskets — replace gaskets or tighten bolts.

5) Fuel system — petrol vs diesel
Petrol (carburettor) components and theory
- Fuel tank → fuel tap → filter → carburettor → combustion. Carburettor uses venturi to draw fuel.
Symptoms: no fuel, flooding, poor idle, stalling.
Diagnostic steps
- Ensure fuel tap is on and tank not blocked. Check for water or contaminants in tank.
- Check fuel filter for blockage. Replace if dirty.
- Check fuel flow: disconnect fuel line to carb bowl, open tap and see steady flow (use pan).
- Inspect carburettor: float stuck will cause flooding or starvation. Check jets for blockage; clean with carb cleaner.
- Choke operation: ensure it opens/closes freely.
Common faults and fixes
- Blocked fuel line/filter — replace/clean.
- Faulty float/needle — rebuild carb or replace parts.
- Bad fuel (old) — drain, clean, refill.

Diesel components and theory
- Diesel: tank → lift pump → primary filter → injection pump → injectors → combustion. Diesel depends on clean fuel and no air in system.
Symptoms: hard/no-start, rough running, power loss, white/grey/black smoke depending on cause.
Diagnostic steps
- Check for fuel in filter bowl and tank. Drain and inspect for water (water separates in primary filter).
- Bleed air from system: open bleed nipples on pump and/or injectors while cranking until fuel flows without bubbles.
- Check injectors: perform “backleak” or spill test if you know procedure to check spray pattern (spray should be fine mist).
- Check injection pump drive timing if pump incorrectly timed (harder job — may need specialist).
Common faults and fixes
- Air leaks in feed line, cracked hose — replace hose and clamps.
- Clogged filter — replace primary and secondary filters.
- Worn lift pump — replace.
- Faulty injectors or pump — clean/overhaul or replace.

6) Ignition system for petrol engines
Components and theory
- Spark plugs, HT leads, coil, distributor/points or electronic ignition. Spark must be timed to compress stroke.
- Analogy: spark = match lighting the fuel. If weak or missing, combustion fails.
Diagnostic steps
- Remove a spark plug, reconnect to lead, lay electrode against engine block (ground) and crank — look for a strong blue spark.
- Check plug condition: oily = oil consumption, black sooty = rich mixture, white/ash = lean/overheating. Replace plugs if fouled/worn to correct gap.
- Check coil primary/secondary resistance with multimeter per coil specs (if available). Test for HT lead continuity.
- If points-type distributor: inspect points for pitting, set gap; check condenser.
- If timing adjustable, use timing light to set ignition timing to factory spec.
Common faults and fixes
- Fouled/worn plugs — replace and gap correctly.
- Bad coil — replace.
- Worn distributor shaft/points — rebuild or convert to electronic ignition.

7) Compression test (mechanical health)
Components and theory
- Compression is produced by pistons, rings, valves and head gasket sealing. Without compression combustion energy is lost.
- Analogy: like pumping a bicycle tire — need pressure to get the job done.
Diagnostic steps
- Warm engine to operating temperature (warm oils expand for good seal).
- Disable fuel or ignition to avoid engine running while cranking: for petrol, disconnect coil; for diesel lock shutoff or disable pump.
- Screw compression tester into spark plug/injector hole; crank engine several revolutions with choke closed for petrol until peak reading stabilizes.
- Good test = similar readings on all cylinders. Absolute value depends on engine spec — for many older small tractors a common expectation is a healthy and fairly high compression; more important is that cylinders are within ~10–15% of each other. If one cylinder is much lower, suspect valve or piston/ring issue.
Interpretation and common faults
- Low on one cylinder: bent/burnt valve, sticky valve, blown head gasket at that cylinder, broken ring, scored cylinder wall.
- Low on all cylinders: timing wrong (valves open at wrong time), cam chain/gear failure, worn rings.
- If low, do a wet compression test: add a teaspoon of oil to the cylinder and repeat. If compression rises significantly, rings are worn; if not, valves/head gasket.

8) Valve and timing checks (loss of power, knock)
Components and theory
- Valves must open/close at the right times (camshaft, pushrods, rockers). Incorrect clearance or timing causes rough running, loss of power, and can damage engine.
Diagnostic steps
- Check valve clearances (rocker adjustment) cold according to MF spec — if excessive lash, noisy and weak; if too tight, valves may not seal and compression drops.
- Inspect cam followers and pushrods for wear.
- Check timing gear condition. If timing belt/chain/gears slip, serious work needed.
Common faults and fixes
- Improper valve lash — adjust.
- Worn rockers/pushrods — replace.
- Slipped timing gear — set timing properly; if damaged, remove head/gear for repair.

9) Lubrication and oil pressure (overheating, noise, wear)
Components and theory
- Oil pumps circulate oil to bearings and cam. Low pressure leads to bearing wear and knocking.
Diagnostic steps
- Check oil level and look for milky oil (coolant mixed) or metal flakes.
- Observe oil pressure gauge or light. If low pressure: warm engine, note pressure. Use mechanical gauge if suspect instrument failure.
- Causes: low oil, clogged pickup, worn pump, worn bearings.
Common faults and fixes
- Low oil: add correct oil grade.
- Dirty oil or filter: change oil/filter.
- Blocked pickup or worn pump: drop oil pan and inspect, replace pump as needed.

10) Cooling system (overheating)
Components and theory
- Radiator, coolant, water pump, thermostat, fan, hoses. Cooling removes combustion heat; circulation and thermostat regulate flow.
Diagnostic steps
- Check coolant level, leaks, radiator fins clean.
- Check fan belt and pump operation.
- If overheating: check thermostat operation (cold engine, feel upper hose — it should stay cool until thermostat opens; warm engine it should be hot and flowing).
- Check radiator cap and pressure. Radiator blocked: run with cap off (careful) and observe coolant flow; if little flow at high temp, radiator blockage or water pump failure.
Common faults and fixes
- Collapsed/blocked radiator or hoses — flush or replace.
- Bad thermostat — replace.
- Failed water pump — replace.
- Air pockets after repairs — properly bleed cooling system.

11) Exhaust and smoke diagnosis (colour of smoke tells story)
- Black smoke: rich mixture (too much fuel) — carburettor adjustment, clogged air filter, injector over-fueling.
- White/grey smoke (diesel): unburned fuel or coolant leak (white steam), weak combustion — compression or injector issue; coolant in oil indicates head gasket.
- Blue smoke: oil burning — worn rings, valve seals, or overfilled oil.
Diagnostic steps
- Match smoke type to likely system and test accordingly: compression, seals, injectors, filters.

12) Noises and vibrations
- Knocking or tapping: bearing wear, rod knock, loose tappets.
- Hissing: vacuum leaks or exhaust manifold leak.
- Squeal: slipping belt.
Diagnostic approach
- Use a stethoscope or screwdriver handle to localize noise; check oil pressure and valve clearance.

13) When to repair vs replace or get specialist help
Do yourself:
- Fuel filter/line replacement, air filter replacement, spark plug replacement, battery, belts, simple carburettor cleaning and adjustment, basic bleeding of diesel lines, valve lash adjustment, tightening/cleaning electrical connections.
Get a shop or specialist:
- Major top-end repairs (head removal, valve seat work), injection pump overhaul, major bearing/rod crank repairs, timing gear replacement, complex electrical refurb (dynamo overhauls) unless you have experience/tools.

Common MF35-specific pitfalls (practical notes)
- Old fuel lines and rubber can become porous causing air leaks — replace with proper fuel-rated hoses.
- Many vintage tractors have 6 V electrics: swapping in 12 V devices without converting charging system confuses diagnostics; always identify system voltage.
- Carburettors may be original SU or Zenith style — cleaning may require a rebuild kit.
- Early tractors used mechanical regulators and dynamos that need brushes and regulator settings to function properly — replacement with modern alternator conversion can simplify later diagnostics.

Typical diagnostic checklist (concise)
1. Visual: fluids, leaks, belts, filters.
2. Battery: voltage at rest and under cranking.
3. Starter: secure, draws current, cranks fast.
4. Fuel: is fuel getting to carb/pump, filters clean, no air.
5. Air: air filter and intake leaks.
6. Spark/injectors: spark present (petrol) or injectors spraying (diesel).
7. Compression: cylinders similar in reading; wet test if low.
8. Ignition timing/valve lash: correct settings.
9. Charging & wiring: charging voltage correct while running.
10. Cooling & oil: levels, pressure, thermostat, leaks.

Final practical tips
- Work methodically; fix one thing at a time and re-test.
- Keep a small notebook of voltages/compressions and symptoms before/after fixes.
- Label hoses and connections when disassembling.
- Replace small wear parts (filters, plugs, hoses) first — cheap and often solve issues.
- When in doubt with fuel injection/pump timing or major engine internal work, use a specialist or workshop manual with MF35 specs.

This covers what each component does, why problems occur, tests you can do, what typical fault signs mean and basic fixes. Follow safety, verify whether your MF35 is petrol or diesel and 6 V or 12 V, then use the appropriate section above.
rteeqp73

### Shock Absorber Replacement on Massey Ferguson MF35 Tractor

#### Tools Needed:
1. **Socket Set** (including 1/2" and 9/16" sockets)
2. **Wrench Set**
3. **Torque Wrench**
4. **Jack and Jack Stands**
5. **Pry Bar**
6. **Screwdriver** (Flathead and Phillips)
7. **Hammer**
8. **Safety Glasses**
9. **Gloves**
10. **Replacement Shock Absorbers**

#### Safety Precautions:
- **Wear Safety Glasses and Gloves**: Protect your eyes and hands from debris and sharp edges.
- **Work on Level Ground**: Ensure the tractor is parked on a flat surface.
- **Use Proper Jack Stands**: Never rely solely on a hydraulic jack; use jack stands to support the vehicle.
- **Disconnect Battery**: Prevent accidental electrical shorts or starting.

#### Step-by-Step Procedure:

1. **Preparation:**
- Ensure the tractor is off and parked on a level surface.
- Disconnect the battery to avoid any electrical issues.

2. **Lift the Tractor:**
- Use a hydraulic jack to lift the rear of the tractor.
- Secure it with jack stands to ensure stability.

3. **Access the Shock Absorbers:**
- Locate the rear shock absorbers, which are usually mounted to the chassis and axle.

4. **Remove the Old Shock Absorbers:**
- **Top Mount**: Use the appropriate socket to remove the nut securing the top of the shock absorber. If necessary, use a pry bar to hold the shock in place.
- **Bottom Mount**: Repeat the process for the bottom mount. Ensure all nuts and bolts are kept for reuse unless new ones are included with replacements.

5. **Inspect Components:**
- Check the mounting points for any signs of wear or damage. Replace any worn mounting hardware if needed.

6. **Install New Shock Absorbers:**
- **Bottom Mount**: Position the new shock absorber and secure it with the bolt and nut. Tighten to the manufacturer’s specifications using a torque wrench.
- **Top Mount**: Repeat the process for the top mount.

7. **Check Alignment:**
- Ensure the new shock absorber is aligned correctly and not under tension or misaligned.

8. **Lower the Tractor:**
- Remove the jack stands and carefully lower the tractor back to the ground.

9. **Reconnect Battery:**
- Reconnect the battery terminals.

10. **Test Drive:**
- Take the tractor for a short test drive to ensure the shock absorbers are functioning correctly.

#### Common Pitfalls to Avoid:
- **Neglecting to Use Jack Stands**: Always secure the tractor with jack stands when working underneath.
- **Overtightening Bolts**: Overtightening can strip threads or damage components; use a torque wrench for accuracy.
- **Ignoring Worn Mounting Hardware**: Always inspect and replace any worn bolts or nuts to ensure a secure mount.
- **Not Aligning the Shock Properly**: Misalignment can lead to premature wear or failure of the new shock absorber.

### Replacement Parts:
- Ensure to acquire OEM or compatible replacement shock absorbers specifically designed for the Massey Ferguson MF35. Check with local dealerships or trusted parts suppliers.

By following these steps carefully and adhering to safety precautions, you can successfully replace the shock absorbers on a Massey Ferguson MF35 tractor.
rteeqp73

Tools & supplies
- Floor jack (2‑ton or greater) and heavy-duty axle stands (rated).
- Wheel chocks.
- Socket set (metric and imperial), breaker bar, ratchet, extensions.
- Torque wrench.
- Impact wrench (optional) — speeds removal.
- Long pry bar, large screwdrivers.
- Drift punches and hammer.
- Pin punch / punch set.
- Hydraulic or arbor press (or large bench vise) for pressing bushings/pins.
- Ball-peen hammer, cold chisel.
- Wire brush, emery cloth, Scotch-Brite.
- Penetrating oil (e.g., PB Blaster), anti-seize.
- Grease gun and lithium grease.
- Threadlocker (medium strength).
- Replacement bushings/pins, grease nipples, bolts/nuts (new hardware recommended), replacement suspension arm if cracked.
- Safety gloves, eye protection, steel-toe boots.
- Welding equipment & filler rod (only if experienced welder/structural repair required).
- Service manual for MF35 (for torque specs, diagrams).

Safety first (must follow)
- Park on level ground, set parking brake, chock rear wheels.
- Disconnect battery negative (if removing/hitting any components near electrics).
- Use rated jack and two stands under sturdy frame points — do not rely on jack alone.
- Wear eye and hand protection; keep bystanders clear.
- If welding, remove grease/grease nipples, clean thoroughly; ventilate well; only qualified welder should weld structural arms.
- If parts are heavy, get help or use lifting gear.

Symptoms that mean the suspension (radius/swing/locating) arm needs repair
- Clunking or knocking over bumps.
- Excessive play at the wheel/steering.
- Uneven tire wear.
- Visible cracks, bent arms, or worn bushings/pins.

High-level procedure (step-by-step)
1) Preparation
- Park, chock, disconnect battery negative, lower implement if attached.
- Consult MF35 manual for component identification (front radius arm, lower link, etc.) and torque specs.
- Spray bolts/pins and joints with penetrating oil; let sit 10–20 minutes.

2) Lift & secure
- Jack the front axle and place axle stands under the frame or designated lift points. Ensure tractor is stable.
- Leave some load on stands so axle hangs naturally — prevents spring binding.

3) Remove wheel & brakes (if needed)
- Remove wheel lug nuts and wheel. Keep lug nuts in marked bag.
- On MF35 front axle you may need to remove hub/axle nut or drum to gain access to the arm pivot — follow manual for hub removal.
- Use impact or breaker bar to remove stubborn nuts. Use a drift to free stuck hub/dust cap parts.

4) Support axle & prepare to remove arm
- Support axle housing so it won’t drop suddenly when arm is unbolted (jack or second stand).
- Identify arm pivot pins/bolts. Typically the suspension arm is retained by a large pivot pin or bolt and nut, and possibly an outer connection to the steering knuckle/axle.

5) Remove pivot pins/bolts
- Remove cotter pin(s) and nuts. Use a punch/drift to drive out pivot pins. If pins are seized, apply penetrating oil, heat (acetylene/oxy-acetylene cautiously) to the nut area only — do not overheat bushings.
- If a pivot pin is pressed in, use an arbor press or punch from inside out while supporting the arm.
- Keep track of shims/spacers and their order.

6) Remove the arm
- Once pins are out, withdraw the arm. If stuck, use careful leverage/heat but avoid twisting the axle housing.
- Inspect arm for bends, cracks at welds or holes. If cracked, replacement is strongly recommended; welding is a last resort and must be done by a qualified welder with proper preheat/post-weld treatment.

7) Remove old bushings and pins
- Press or drive out worn bushings and sleeves using hydraulic/arbor press or bench vise with appropriate receivers. Use proper tooling to avoid distorting the arm bore.
- Clean the bore with wire brush and emery cloth until smooth. Remove corrosion and old grease.

8) Inspect mating components
- Inspect pins, sleeves, spindle/knuckle bores, and bolt holes. Replace worn pins/sleeves; do not reuse grooved or heavily worn pins.
- Inspect seals and grease nipples; replace if damaged.

9) Install new bushings/pins
- If using replaceable bushings/sleeves: press new bushings squarely into place using press and correct-sized receivers. Lightly oil or use assembly lube per parts instructions.
- Fit new pivot pins/sleeves. If pins are tapered, ream or fit per spec.
- Install new grease nipples in provided holes and tighten to spec.

10) Refit arm to tractor
- Reinstall arm, shims, spacers in original order. Slide pivot pin through. Install new nuts and cotter pins or locking plates as originally used.
- Apply medium threadlocker on threads if recommended in manual. Torque bolts to OEM specs (consult MF35 manual). If manual unavailable, tighten progressively and check play — do not over-torque.

11) Reassemble wheel/hub
- Reinstall hub, brake drum, wheel. Torque wheel nuts to spec.
- Reconnect any removed steering/tie rods and tighten to spec. Replace any worn tie rod ends.

12) Lubricate and test
- Grease all new nipples until clean grease appears at seals.
- Lower tractor and remove stands. Torque axle/hub fasteners final if needed.
- Start tractor and test: drive forward/back a short distance, steer, and listen/feel for clunks. Re-check all fasteners and grease levels after first couple hours of operation.

If welding repair is required
- If arm has hairline crack, assess location: cracks in high-stress areas normally require replacement.
- If welding: remove arm from tractor, strip grease/paint, preheat to recommended temperature for the steel (~150–200°C depending on grade), weld with appropriate filler (e.g., low-hydrogen electrode or ER70S filler for mild steel), and perform post-weld stress relief if possible. Only experienced welders should perform structural repairs. After welding, check alignment and consider reinforcing with OEM overlap plate if available.

Common pitfalls & how to avoid them
- Relying on a jack alone — always use stands.
- Reusing worn bushings/pins — leads to rapid recurrence of play. Replace bushings/pins when wear is evident.
- Overheating components — heat can ruin temper in nearby parts and seals.
- Improper pressing technique — pressing at an angle will distort bores. Use proper receivers and center the bushing.
- Not replacing small hardware (cotter pins, Nyloc nuts, grease nipples) — cheap parts but critical for safety.
- Incorrect torque — too loose = play, too tight = premature bushing wear. Use torque wrench and manual specs.
- Welding without proper procedures — can cause brittle repairs and failure.

Replacement parts typically required
- Pivot pins/sleeves (OEM or aftermarket service kits).
- Press-fit bushings or bronze sleeves.
- Grease nipples (zerk fittings).
- New nuts, bolts, and cotter pins (replace rather than reuse).
- Replacement suspension arm if bent/cracked beyond repair.
- Seals/axle bearings (if hub removed and worn).

How specific tools are used (short)
- Floor jack/stands: lift and safely support tractor.
- Penetrating oil + heat: free seized nuts/pins; heat applied only to nut area briefly.
- Drift/punch: drive out pins after nut removed; use correct size to avoid mushrooming pin ends.
- Arbor/hydraulic press: press bushings/pins in and out squarely; support surrounding metal to prevent bend.
- Torque wrench: final tightening to spec.
- Grease gun: fill fresh grease into new nipples until seals are lubricated.

Final checks
- After 10–50 miles of use, re-check torque on all fasteners and re-grease.
- Confirm steering alignment and absence of play; adjust tie rods if needed.

Done — follow the MF35 service manual for exact part numbers and torque values.
rteeqp73