Fordson Major Page



From the time of it's introduction into the UK in 1952, the Fordson Major underwent numerous changes to the mechanicals whilst generally keeping the original looks of the tractor.
The data below is a summary of the various changes from introduction of New Fordson Major to final model of New Super Major. This table only deals with the Diesel Major. The first models were also available with 4 cylinder Petrol and Vapourising Oil Engines with capacities of 3.26 and 3.61L. These engines have bores of 95mm and 100mm respectively, both with 115mm strokes. Petrol engine compression ratio is 5.5:1, Vap. oil engine 4.62:1 (early type 4.35:1)


Identification of Petrol / Vapourising Oil Cylinder Heads.

Fuel Compression Ratio Identification
Petrol 5.5 : 1 E1ADN-6050-B cast between Nos. 2 and 3 exhaust ports.
Vap. Oil 4.62 : 1 E1ADN-6050-B cast between Nos. 2 and 3 exhaust ports and letter 'H' embossed between Nos. 2 and 3 spark plugs.
Vap. Oil 4.35 : 1 E1ADN-6050 cast between Nos. 2 and 3 exhaust ports.



Diesel Major Changes


Engine No. Serial No. Change Date
1217101 to 1425096 Introduction of "New Fordson Major" MARK I ENGINE. Injection timing 26 deg. BTDC 1952

1257972

 Rotator type exhaust valves introduced

1290291

 Decompressor repositioned from rear to front of engine

1308977

 Changes to size of fan belt and pulleys (narrower)

1356500

 Modified fuel lift pump

1358273

 Chilled camshafts and tappets introduced

1362380

 Solid piston pin introduced

1367376

 Modification of Differential case.

1384132

Modified hydraulic control valve piston

1406540

Optional heavy duty rear axle shafts and housings.

1417988

 Introduction of 'Live PTO'

1418861

Standardisation of bell housing for non 'live' and 'livePTO'

1420356

New Radiator (old type 10 fins per inch, New 5 per inch)

Inj. Pump no. 34624

Modified Pump inspection cover with 8 bolt fixing.

Inj. Pump no. 37476

Govenor link fixing modified. Increased size vacuum and air bleed pipes (1/2" 20NF2 to 9/16" 18UNF). Modified stop control housing fixing. Round control rod fitted

Inj. Pump no. 39001

Deletion of fuel pre filter in pump body.

Inj. Pump no. 40268

Pump tappet bodies, spacers and circlips modified.

Inj. Pump no. 52205

Pump mounting bracket modified from vertical to 10 deg. Pump tilt. Modified pump camshaft, longer injector pipes.

Inj. Pump no. 61994

7mm pump plungers with 50 deg. Helix. Modified excess fuel device. (push for excess fuel)

1425097 to 1481090

 MARK II ENGINE

July 1959

1425097

Water pump enlarged by-pass port - changed gasket. Shrouded thermostat fitted. Valve rotator cap and collets size increased. Spring retainer changed. Oil Breather on timing cover - oil slinger on front of auxiliary drive shaft gear. Reduced diam. Oil return front main bearing cap (5/8" - 5/16"). New oil pump with integral pressure relief valve. New pistons (offset combustion cutout, reduced height, hollow piston pin, increased piston pin diameter (to 34.9mm)). Steel crimped Cylinder head gasket.New front engine plate. Sump changed - No inspection cover. Oil pickup filter changed. New Cylinder Head (inline ports). Shorter push rods(299.7mm). New injectors (nozzle no. NL141). Injection timing 19 deg. BTDC (23deg. with latest head gasket). Equal length injector pipes. Pump plungers 7.5mm 50 deg. helix. Changed throttle linkage.

1426221

Voltage regulator changed.

1435545

Modified main drive shaft sliding gear and selector shaft.

1436181

Selector spring and ball hole in primary gearbox modified to prevent spring coil binding

Inj. Pump no. 176929

Inj. Govenor spring rate changed, incl. Changed gov. components.

1445056

Horseshoe' shaped camshaft thrust washer introduced

1458847

Common length valve guides introduced. Cup type valve stem seals fitted.

1481091

 MARK III ENGINE Power Major introduced

1481091

New Camshaft lobe form. Shorter 'right handed' rocker arms than Mk I & Mk II. Revert to Mk I engine injectors (nozzle no. N123). Injection timing 23 deg BTDC. Modified inj. Pump plunger travel. Oil pressure switch replaces gauge. Mounting for voltage regulator on air filter.

1483140

Increased fillet radius between Crankshaft webs and journals. Narrower Con.rod and main bearing liners. Increased ID Crankshaft thrust washers

1493622

Modified live PTO input shaft seal

1502511

Modified hydraulic unloading valve.

1509598

Longer connecting rod bolts

1511488

Redesigned camshaft thrust washer

1518654

New piston together with copper/asbestos permanite gasket and spigoted liners

1524750

Modified Clutch cover

1529773

Redesigned timing cover breather

1531530

Modified gearbox main upper shaft rear bearing (ball to roller)

1565580

New composition cylinder head gasket and liners with smaller spigot

1575886

 Super Major introduced

October 1960

1575886

New rear transmission case and hydraulics. Diff. Lock fitted. Disc braked fitted. Lower hydraulic Arm balls changeable. Modified lower arm check chains. Modified hydraulic leveling box. Larger front axle trunion pin. Heavier front axle cross member. Rubber front axle spindle dust seals. Modified steering drop arm

1584892

Modified hyd. Control valve piston

1589010

Modified hyd. Feed pipe and bracket

1591023

Cylinder liners with two seals and larger diameter main bearing bolts

1594009

New exhaust valve, collets, retainers and rotator cap New collet thickness 7/32"

1595085

New material oil pump drive gear and auxiliary drive shaft gear

1599502

New camshaft and timing gears(wider gears), front mounting plate etc. Suspended fitting of camshaft thrust washer. New fuel injection pump coupling-keyway increased to 3/16" wide (formerly 5/32") Clamp slot angled to pinch bolt.

1607304

Lockwashers on valve rocker brackets

1609839

New cam form on camshaft and heavier valve springs

1613500

New type lift pump introduced and cylinder block changed

1622437

New 'cushioned' 12" clutch disc.

1623034

Radius rod pin retained with double tension pins or solid clevis pin

08A302897

Modified main gear lever (straight)

08A303242

Modified hydraulic Feed pipe and bracket

08B743082

Improved gear change plungers and springs

08B746216

Modified hydraulic back pressure valve body

08B747301

Modified hydraulic unloading valve seal

08B752791

Cylinder block modified and oil drain hole added to auxiliary drive shaft bore

08B756398

Minimec fuel injection pump introduced. Injection timing 21 deg BTDC

April 1962

08B756400

New rotator caps with black anti-friction coating (OD 15.49-15.60mm)

08B756500

New fuel injection pump coupling (pinch bolt instead of Allen screw and slot at right angles to pinch bolt)

08B764393

Modified hydraulic Spool and housing

08B767403

New radiator and fixings

08B767745

Increased diam. Gearbox upper shaft rear abutment bearing boss.

08B771912

Industrial tractors 13" clutch introduced.

08B775949

Reinstatement of unmodified hydraulic spool and housing (see08B764393)

08C955882

Modified hydraulic Pressure relief valve

08C960337

 New Super Major introduced.

Agricultural tractors modified double clutch. New PTO disc with rivited linings to spring plates. Modified primary uppershaft and main lower gears. Larger capacity bearing fitted primary lower mainshaft. Modified primary lower mainshaft.New heat treatment primary lowershaft gear. Modified reverse idler gear and hub assy. New main upper shaft gear - new transmission large gear.New main shaft low gear. Changed gear ratios on hyd. pump. Modified hyd. system. Modified PTO housing and lever (offset reduced to 23.8mm from 39.62mm) Modified PTO gear ratios. Larger PTO extension tube (2"1/8) New PTO selector fork.Modified PTO gears and heat treatment.

October 1963