In its day, the Ford TW-25 Force II was an impressive powerhouse.
Regular Farmers Guardian machinery writer Geoff Ashcroft happened upon a genuine example and has spent the last six months returning it back to rude health...
Condition is everything and buyer beware are frequently used phrases to warn others about stepping into a relatively unknown tractor purchase.
The tractor in question is a 1988 Ford TW-25 Force II, equipped with Zuidberg front linkage and three spools.
Having spent the bulk of its working life on an arable farm in Lincolnshire, the 6,400-hour tractor was living out its retirement on a mixed farm in Dorset, but doing perhaps, much more than was originally intended. It was broken.
While the tractor was in desperate need of a tidy up, it also needed some mechanical intervention.
Blowing blue smoke and struggling to make enough power to pull itself along, the only certainty was that a local dealership had confirmed the engine’s block was not porous.
Some comfort then, knowing the clutch, gearbox and rear linkage were operational, too.
Externally, its condition was original with signs of surface corrosion, but no rot as could often been found on the Super Q cab.
While coolant and oil condition gave away nothing about engine condition, a left-hand brake pedal which would push to the floor, and a failed rear window compounded the list of jobs needed to get the once venerable TW back to top condition.
With low-loader transport arranged through Ford-owning friend Andrew Walters, the road to recovery was underway. How bad could it really be?
DOWN but not out, the TW-25’s external condition was mostly original, hinting at its time spent in the hands of its first owner, Keith Stephenson, of E.S.G. Stephenson.
Additional front lights helped illuminate beyond front-mounted kit and tyres looked in good condition, as did the original blue paint, though a number of panels did need refixing.
Cast rear wheel centres with PAVT (Power Adjustable Variable Track) rims can carry five 39kg weights on the outside and a single inner weight of 222kg.
Up front is a full set of 16 wafer weights adding 720kg to the nose and, with a recommended gross vehicle weight of 8,165kg, a total of 1,554kg can be removed.
THE original seat fabric remains intact, and pedals, controls and interior trim is barely worn too, suggesting its 6,400 clock hours is fairly genuine and not on its second time around.
Cab headlining needed only a vacuuming to remove dust.
Original Ford LW/MW radio and LCD clock still function, as do all controls.
The TW’s colour-coded levers make it easy to fathom out spool selection and pto controls. An original window sticker informs of pto settings, gears and forward speed charts for the eight by two constant mesh transmission.
With a floormounted Dual Power split, there are 16 forward and four reverse gears, and a giddy road speed of 30kph (18mph).
PEELING off the rocker cover revealed the tractor’s power deficit.
Loose valve clearances and one pushrod detached from an intake valve were the main culprits of poor performance.
Further dismantling found two bent pushrods, confirming that valves and pistons had met. Could cam timing have slipped or timing gears be broken?
With the cylinder head removed, pistons and bores could be thoroughly inspected.
While loose valve clearances contributed to the poor running, the tractor’s partly failed braking system had a role to play too - this TW could easily have been ‘pushed’ downhill, causing the engine to be accidentally over-revved.
MOVING the crankshaft round by hand allowed the fuel injection pump timing to be checked, to confirm timing gear integrity.
With the cylinder head stripped of its damaged valves and thoroughly checked over, head gasket failure could be ruled out.
A new set of intake and exhaust valves were fitted and lapped in and the cylinder head could be refitted on top of a new gasket.
After correctly torqueing the head, new pushrods were installed and the valve train inspected before being refitted.
Valve clearances could then be correctly set, and the rocker cover refitted. With fuel injectors overhauled too, poor combustion could then be ruled out.
THE tractor’s turbocharger is a nonwastegate, non-variable geometry unit and is mechanically simple, but its near 7,000-hour lifespan hints at worn bearings and possibly end-float.
Careful dismantling revealed the exhaust turbine and compressor wheel were in good condition, and this unit could benefit from a simple rebuild.
With a service kit sourced through friend, tractor puller and dairy farmer Peter Clarke, the Garrett T04 gained a new thrust washer plate and rubber seal, two journal bearings and retaining circlips, piston rings and a left-hand nut to secure the compressor wheel to the exhaust shaft.
With a repainted exhaust housing and central core, plus bead-blasted compressor cover, this unit looked like new, and could be refitted to the engine using new gaskets.
AFTER decontamination and multiple washes to remove years of grime, the TW’s true condition could be assessed.
In 2014, with 6,071 hours, the engine had been stripped and rebuilt by its first owner, to deal with known porosity issues.
There were no signs of blow-by from the engine’s breather, suggesting good sealing from the bores and piston rings.
The plan was to remove the cylinder head and check its gasket.
Piece by piece, the TW’s front end was dismantled, allowing access to the top of the engine.
It meant the long bonnet, air filter box, inlet, turbocharger, exhaust silencer and manifold, plus auxiliaries and fuel lines were carefully removed, before delving beneath the rocker cover.
THE TW’s lower rear window had become detached from its upper section, though all glass was present and intact. Hinge failure is common on Super Q cabbed Fords and replacement windows can be costly and increasingly difficult to source.
A replacement piano hinge was used to reconnect the upper and lower glass panes, along with new fittings, gas struts and rubber window seal, as required.
A length of D-profile rubber seal was added to the hinge, creating a seal and cushioning the hinge when the window is kept closed.
WITH the engine successfully repaired, the TW was subjected to a couple of heat cycles to allow fluids to be rechecked when cooled, and topped up as necessary.
A faulty wire resolved a digital dashboard issue and also gave the opportunity to watch vital signs, ahead of its journey to local dealer T.H. White’s dyno.
Here, the engine recorded a peak of 132.5hp at a pto speed of 975rpm (1,872 engine rpm) – just shy of its 140.7hp factory setting.
Peak torque was 759lb.ft at a pto speed of 855rpm (1,641 engine rpm).
FORD’S tractor grey colour scheme is not one that wears well over time.
The TW’s lightly corroding grille panels and peeling rear wings were stripped and refinished, adding much-needed condition to match that of the cleaned and polished factory blue paint.
Tractor wheel rims are likely to receive the same improvement over winter.
Relocating the front lights to their original position on the chassis has also improved its appearance.
IMPROVING versatility has required some updates to the TW’s rear-end.
The twin adjustable lift rods and twin assistor rams offer scope for work, but the original extending link arms had been welded shut.
In addition, the tractor’s category three/two balls restricted implement choices to drawbar or category two use only.
But after a trip to Nottinghamshire-based fabrication friends D. Clifford and Sons, the link arms were modified to accept a Sparex category three hook-end kit, to increase flexibility for working days.
THE TW’s original owner still had the tractor’s full set of Stocks dual wheels and, once acquired, these were refurbished in Ford tractor grey to match the tractor’s recently renovated rear wings and grille panels.
Original dual wheel fixings comprised six for each rear wheel and, oddly, just three for each front wheel - two additional eye bolts, clamps and hooks were supplied by Stocks Ag to increase front wheel fixings to four per side.
With the front axle exhibiting signs of lifting under heavy load, a 500kg front weight box was sourced, completing the tractor’s fresh new look.