The TR4/TR4A’s 2138cc four-cylinder powerplant is simple, strong and reliable. Derived from the post-war Standard Vanguard unit, it’ll cover 100,000 miles before needing significant attention, although oil leaks from the timing chain cover are an expected part of Triumph ownership. The scroll seal fitted at the rear of the crankshaft also lets oil out; this is only a problem when the engine is running but the vehicle itself isn’t moving. Once the engine is up to running temperature you should be seeing 70psi on the gauge.
TR5 and TR6’s smooth 2.5-litre straight-six offers huge reserves of
torque. With regular oil changes and proper servicing the units will
take 120,000 miles quite happily – some owners have seen more than
twice this before major surgery is required.
Check for play
in the crankshaft thrust washers by pushing and pulling on the bottom
pulley. The job is made easier by depressing and releasing the clutch –
there should be no more than 0.008in movement. It may also be possible
to feel and hear a clonk as the crank moves. Any detectable movement
means the thrust washers may have dropped out, which could be serious
and may involve the sourcing of a replacement block or even engine. If
the thrust washers are still in place it’s possible to replace them
with oversized ones, without having to remove the engine first.
if the original canister type of oil filter has been replaced with a
spin-on version – they cost less than £40 so if there isn’t one there
you’ll get an idea of how well kept the car is. The original filters
had no anti-drain valve, leading to the bearings being starved of oil
on start up, whereas the spin-on type keeps the system primed allowing
the oil to circulate much more quickly. Once up to temperature check
the oil pressure; it should be showing 50-60psi on the dial at 2,500rpm.
engine is also famed for oil leaks, and rattles at start up. Thankfully
these characteristics can be engineered out without too much difficulty
or expense. All parts are readily available, and it’s an easy engine to
cut your teeth on if you’re buying a project.
It won’t be
hard to spot if the engine has worn out. Blue smoke when the car is
accelerated points to bore and/or piston wear, while blue smoke when
the engine is started indicates worn valve guides – and the requirement
for a cylinder overhaul. Rebuilt unleaded heads are available for
around £300 to fit yourself or from £500 to have someone do it for you.
If you can see black smoke as the car is accelerated quickly, it’s
because the fuel-injection metering has been set up to run rich. Not
only will this mean steep fuel bills but it will also make for
premature bore wear if it’s been that way for a while.
well known fuel injection problems revolve around difficult starting
from hot, fuel vaporisation and misfiring on start up. These are well
known problems and easily remedied by one of the many specialists, or
the job can be done at home without any special tools. All parts for
the injection system are readily available either on an exchange basis
or even outright on a number of components. A common conversion on the
fuel-injection system is the replacement of the Lucas pump with a Bosch
item, which solves most of the problems of overheating for which the
Lucas pump has achieved a reputation.
powerplants are readily available through the basic engine being common
to the 2.5 saloons. Running second-hand engines can be bought from £50,
although you’ll have to spend at least £200 to get one that won’t need
rebuilding before long. However, for the purist who doesn’t want a
saloon engine with an MG prefix, genuine second-hand TR6 engines start
The four-speed gearbox rarely gives problems, as it’s just as tough as the engines. But once 100,000 miles have been racked up the bearings will begin to grumble and it’ll start to jump out of gear. Another common casualty is the layshaft bearings; when cruising you’ll hear a rumbling in all of the intermediate gears, which disappears when top gear is engaged. It can also be identified when the car is stationary with the engine running, by a rumbling noise which disappears when the clutch pedal is pressed down. The only option is a rebuilt gearbox, for which you can expect to pay £350 plus your old one. Overdrive was fitted as an option to give a seven-speed ‘box which gives few problems except for the classic electrical ones in which either the solenoid or the wiring loom play up.
the clutch isn’t set up properly on any of the cars there’ll be
problems. Make sure the clevis pin which connects the clutch pedal to
the master cylinder isn’t excessively worn and that the slave cylinder
is mounted with the bleed nipple facing upwards – the cylinder can be
fitted upside down very easily. This will allow the hydraulics to be
bled properly, as if they’re not, the baulk rings in the gearbox will
take a battering through the clutch not giving the necessary clearance.
around 145lb ft of torque available, the transmission will have taken
quite a beating if the car has been driven hard. Accordingly, universal
joints on the propshaft and half-shafts may be worn; listen for clonks
as drive is taken up when the car is driven off. Also get underneath
the car and look at the differential’s mounting points, which can be
distorted or even torn away by repeated fierce acceleration. Because of
the torque levels, the clutch may have seen better days. Make sure it
engages smoothly and disengages well before the pedal reaches the end
of its travel.
Overdrive wasn’t fitted as standard until
1974, and it’s worth buying a car with it. If fitted but faulty, it’s
probably wiring problems, which are easily fixed. Look out for things
like broken wires, dodgy relays or loose Lucar connections. It could be
because the overdrive unit has clogged up inside or because the
solenoid has packed up. CP, CC and CR series TR6 up to commission
number CR641 had an A-type overdrive unit fitted. The CF and CR series
cars (from CR567) were fitted with a J-type unit. Overdrive solenoids
are available from £80, but if the unit just needs cleaning out it will
take only a morning of your time.
Check for wear in the
propshaft and driveshaft universal joints by using a wrench to turn the
shafts while the brakes are on. Any play will be instantly noticeable
and if the propshaft is worn out you’ll have to pay around £150 to
replace it. Also check for wear in the driveshaft splines which cost
around £165 each side to fix – if you’re having to replace these it’s
worth investing in a fresh, stronger set from Neil Revington, which are
better made and longer lasting. Propshafts need to be greased every
3000 miles if they’re not to seize and they can also go out of balance
when the universal joints are replaced, so make sure they’re
reassembled in the correct way.
Suspension, steering and brakes
Neither the front nor the rear suspension have any inherent problems, although the rear of the TR4A can be improved by fitting telescopic shock absorbers. Uprated springs are available for the TR4, and these should be fitted without the aluminium spacer that normally lives between the top of the spring and the top spring mounting. But many DIY owners don’t read the instructions and end up fitting the whole lot, which raises the ride height and upsets the handling. You should be able to get just two fingers between the top of the tyre and the rear wheelarch – any more and it’s sitting too high, probably because it’s riding on the wrong springs.
The front trunnions have a habit of
seizing because they haven’t been lubricated properly when fitted. This
strains other parts of the suspension – especially the drop link on the
wishbone – so check their condition by jacking up the car from
underneath the wishbone and making sure the trunnions are swivelling
properly. Wheelbearings aren’t renowned for their strength; play can be
adjusted out, but count on having to replace them if you notice any
If wire wheels have been fitted, you need to check for
loose or rusty spokes as well as rim corrosion. The splines that hold
the wire wheel hubs in place can also wear, so jack up each corner and
check for play by trying to rock then spin the wheel while the
footbrake is applied. Any obvious movement between the wheel and the
hub means the splines have worn. A replacement set costs around £250
including the spinners. Conversion between wires and steel wheels is
easy on these cars because the same hubs are used for either model and
conversion requires only shortened wheel studs to go along with the set
of wire wheel spline adaptors.
Brakes have no inherent
problems, but if there is a fault of any sort it’ll be easy and cheap
to fix. The brakes have an in-line servo as standard and unless the car
has been uprated the stoppers are more than adequate for the purpose.
However, the handbrake is poor even with everything in good condition.
Servo assistance was an option on the TR4 and TR4A, but standard on the TR5 and TR6, so don’t always expect to see one fitted to earlier cars. Whether or not there’s one fitted, the brakes should be up to the job, but the handbrake is notoriously poor at holding the car on a hill.
Bodywork, electrics and trim
These cars have a separate chassis, which can rot in all sorts of places and can only really be repaired properly if the bodyshell is removed first. But the construction of the TR4A, TR5 and TR6 mean many chassis repairs can be undertaken with the body in situ. The worst-affected areas are usually the diff mounting brackets (which can snap off), so pay close attention to what state the offside front and nearside rear units are in, as these are most affected by the torque going through the diff.
centre section of the chassis also needs careful analysis because it
bulges as it gets weaker. TR4s survive the best because the chassis is
less complex – the TR4A-TR6 have internal strengthening where the rear
suspension is bolted to the chassis, and this is an area that corrodes
quite readily. Also, because of the very different shape that the later
cars have from the TR4, these suffer from flexing that can crack the
chassis. These later cars also have differential mounting brackets that
are more prone to problem than those on the earlier TR4. The TR5 and
TR6 is the worst affected of them all, because the amount of torque put
through the diff can cause the mountings to break off altogether.
repaired accident damage is another probability. The chassis isn’t
especially hardy, so even small parking nudges can end up causing
distortion. The areas most commonly afflicted are the front suspension
turrets, the mounting brackets (the points from which the wishbones
pivot), outriggers, steering rack mountings and the suspension itself.
Look for distorted metal (particularly kinks where the chassis gets
wider on either side of the sump), cracks, naff plating and uneven tyre
wear which all give the game away.
Despite the use of a
separate chassis, the bodyshell does give some structural strength,
especially on the TR4A-TR6 which have a more flexible chassis. Because
of this it’s especially important to make sure the main shell is sound
and that the doors, wings, sills and floorpans are in reasonable
condition. Make sure the drain holes, which should be obvious on the
underside of the sill, are all present and correct – if they’re blocked
up then the sills will probably be rotting through from the inside. The
tops and bottoms of both the doors and wings can rot away, and where
the front wings are concerned you have to inspect the inner as well as
the outer wing very carefully. The battery sits behind the engine and
the metal beneath it rots readily, so if it doesn’t look too great
remove the battery and inspect more closely – you’ll probably be glad
Also check the door gaps as they can open up at the
top if the chassis has been weakened by corrosion, or if the car hasn’t
been properly braced when the sills have been replaced. B-posts and
door tops can also succumb to the dreaded tin worm as can the lip of
the boot lid so ignore these and you might just regret it. But if the
panel gaps are excessive or hideously uneven it could be because the
car has been restored very badly. They weren’t put together especially
well on the production line, but most will have been restored by now.
If a car has been badly rebuilt it’ll be a lot more hassle putting that
right than starting with an unrestored example.
of a bodged rebuild is missing beading along the seam between the top
of the rear wings and the deck. The rear wings bolt on and filler is
often used along the tops of them while the beading is left out.
Speaking of bodges, make sure the footwells are in good shape, as a
common bit of sharp practice is to weld replacement panels over already
rusty ones – it might look OK but the corrosion will still be there and
the car may well be weakened structurally as a result.
because TR5s are worth more than TR4As, it’s not unknown for a six-pot
engine to be dropped into a TR4A and passed off as a TR5 – it has to be
a TR4A (and not a TR4) because of the independent rear suspension. A
TR5 chassis number will start CP, while CT means it’s a TR4, CTC is a
TR4A and if it’s a TR250 it’ll start with CD. All these cars have a
commission plate, which is located on the nearside front inner
wheelarch – always worth a look.
Unless the interior
resembles a scene from The Young Ones, a bit of scruffiness inside the
car isn’t anything to worry about because everything is available. The
Surrey hard tops were always an option, and are now sought after – if
the car you’re looking at doesn’t have one but you’d like one, expect
to pay at least £400 for a decent example.
The electrics are
straightforward; if there are any problems, everything can be fixed
easily and cheaply. Replacement parts are cheap and apart from
connections not connecting properly there’s little to worry about. A
new wiring loom is available for about £200 and it’s not that tricky to
fit – a specialist will charge £400-£500 to replace it for you. The
only exception to this is if the windscreen wipers are playing up. If
it’s the motor that needs TLC there’s very little to worry about, but
if it’s the rack that’s unhappy you’ll have to remove the dash to get
If the heater unit seems to be completely ineffective
it’s probably because the air vent at the base of the windscreen isn’t
open. Just raising the flap by a few degrees makes all the difference
between a misted up windscreen and a clear one.
The Americans knew they were onto a good thing, which is why most of these were exported to the US. Now they’re coming back here, and being converted to right-hand drive in the process. Such a job is quite involved but no problem if the car is being properly restored. Also, don’t assume that if you’re buying a car from the US that it’ll be rust-free; they’re often very corroded.
There’s plenty of
scope to buy something that will swallow all the money you throw at it,
but if you take your time and look at plenty of cars, you’ll see there
are some superb examples to choose from.
Buy a good example of any TR, look after it and drive it sympathetically, and you’ll be able to sell it on without losing your shirt on it. If on the other hand you’re looking at buying a car to treat as a project there are plenty of earlier cars on offer (TR5 projects are rarer) along with a decent supply of parts that means you won’t grind to a halt because you’re missing a crucial component.
Whichever route you choose,
get ready to listen to everybody you ever meet while out in your TR,
because they’ll all want to relate at least one anecdote to you about
their friends, relatives or neighbours who ‘used to have one of those’.