Rover 3500 S
35.000 miles - long term
In our 11
October 1973 issue, we reported on the first 16.000 miles with this Rover 3500 S
and explained that the car has given extremely good service and remained
trouble-free. Now continuing the story, we deal with the subsequent 14-month
period, taking the car beyond the 35.000-mile point, and in general the
excellent behaviour has continued.
In a recent
run to familiarize ourselves with the Rover as it is now, it was feared that the
engine was beginning to show its age. Smoke from the exhaust was noticed both on
the overrun and when accelerating hard, and maximum speed tests were quite a
long way down. Instead of 123 mph at 5.130 rpm, the car would not exceed 116 mph
even in a long run with perfect weather conditions.
checks of the service records revealed that renewal of the sparking plugs had
been overlooked at the last service, and nearly 15.000 miles had been covered on
one set of plugs. This had resulted from earlier experimentation with sparking
plugs to find a type which would eliminate misfiring; the service department
were under the wrong impression that a plug change was not yet due. The type
used, incidentally, is Champioen L92Y - the answer for any owners of the model
who suffer misfiring during extensive traffic work.
tests carried out after new plugs had been fitted proved fairly well up to
standard obtained with the model when new. Unfortunately it was not possible, in
the time available for this report, to repeat the maximum speed tests. Smoking
from the exhaust still occurs, particularly on the overrun at speed.
history of the car since the last report has included two medium and two major
routine maintenance attentions. New front disc brake pads have been fitted (at
21.000 miles), and the battery was renewed at 17.800 miles. At renewal, the
battery was only just over a year old, but the earlier report explained there
had been severe corrosion at one of the terminals. Although there is much to be
said for locating the battery in the boot, away from the heat and dirt of the
engine compartment, it inevitably comes in for less regular attention as a
hissing noise is now audible from the power steering when taking sharp corners,
and it could be that trouble is on the way in this quarter. As the noise is
high-pitched and not unlike the beeping of a car horn, it is sometimes
disconcerting until the driver has become familiar with it.
consumption is still negligible and fuel consumption, even on the old plugs, was
still nearly 21 mpg on a long run. In London traffic, mpg falls to the region of
18, which is again moderate for the size of the car and its engine, It is a
nuisance that 5-star fuel is necessary, and we notice that the number of garages
stocking this top grade fuel is ever diminishing. The 15-gallon tank, with
positive reserve controlled by a knob on the console, enables one to put almost
300 miles between fuelling points unless driving very hard.
always reliable although far from prompt when cold. The mixture control has to
be pulled right out, and several turns on the starter are needed before it will
fire; there is some tendency to snatch and hesitate in the first couple of
minutes from cold. Once warmed up, starting is immediate, and the engine is as
crisp and smooth as ever. Engine quietness at all speeds is still outstanding,
and the lack of fuss or apparent stress in 100 mph cruising at just over 4.000
rpm is not equalled by many cars today. The level of wind noise is relatively
high, against the mechanical refinement. Appreciably more engine noise is
heard under hard acceleration particularly in third gear, and it is suspected
that some of the slight roar heard is corning from the gearbox.
smoothness and the precision of the short-travel but rather notchy gearchange
remain up to standard, and it speaks well for the transmission that it has stood
up to a continued exposure to London traffic conditions, not to mention two sets
of performancé tests at MIRA, without need for attention. When examining the
underbody, it was noticed that there has been some loss of oil from the front
seal of the fixed final drive unit. Reverse gear is always rather difficult to
select without an undignified crunch of gears, which is rather irritating.
In all other
respects, the condition of the car underneath, with its almost total lack of
corrosion, is very reassuring and a credit to the effectiveness of Rover
underbody protection. The original equipment exhaust system is still in use and
looks very sound.
always been criticism of the Roverīs rather soft and floating suspension, and in
an effort to improve this, new suspension dampers were fitted at 24.000 miles.
These made little improvement, and were replaced again last month by Koni
dampers front and rear. These have made a major contribution to taughtening the
suspension and giving a better, more positive feel to the car. The tendency to
roll on corners has been slightly reduced, and suspension "float" on undulations
is much less than before, the drawback being that the suspension is now slightly
"knobbly" and harsh on poor surfaces.
miles it was decided to try the car on the new Dunlop Denovo safety tyres, and
the original tyres and wheels were put in storage. The Denovos are mounted on
special wheels with a distinctive trim which, in our view, detracts from the
look of the car; they also need special wheel nuts. The spare wheel is, of
course, dispensed with, and an emergency repair kit is supplied, including a
list of Dunlop repair centres at which a punctured tyre can be properly
thicker tyre wall of the Denovo gives a very firm hold of the tread and makes a
big improvement in roadholding, especially in the wet. This aspect of Denovo, we
feel, has not so far been sufficiently emphasized in earlier tests of the tyre.
There is also a small gain in steering response and directional stability. The
penalty of Denovo, particularly marked on this car, was severe tyre whine and
roar, particularly in the 30-40 mph speed range. Dunlop engineers say that this
problem, accentuated by the Roverīs suspension design in which front wheel loads
are fed back to the scuttle, varies in the 3500 S from one particular car to
another. It was not until the tyre design had been finalized that it was
realized that the two cars being used for research were less prone to this noise
problem. At that stage it was too late to alter the tyre tread pattern, but it
is emphasized that the noise is caused by the particular coarse tread pattern
chosen, and is not from the Denovo safety feature.
the whine, which was proving tiresome at traffic speeds, the decision was taken
to forego the advantages of Denovo, particularly the major advantage of not
having to carry a spare, and revert to the original wheels which had been fitted
with new tyres (conventional Dunlop Sports) shortly before the change to
Denovos. When removed, the Denovos had covered 18.000 miles, and the tread had
worn approximately 4mm at the front and 3mm at the rear. This wear rate was more
rapid than on conventional tyres, perhaps as a result of the rather low pressure
which had been recommended initially. Dunlop now advise normal tyre pressures
for Denovos, which gives a very harsh ride.
Denovos were taken off, it was decided to carry out a deliberate burst at very
high speed.. Endless tests have been made of course, at speeds in the 60-70 mph
region, but the real safety factor of Denovo is the more valuable the higher the
speed. Dunlop kindly co-operated in the tests and although we had wanted to
carry them out on our own car, this proved impracticable because of the
elaborate electrical equipment required to set off an explosive change on the
sidewall. This detonation blows a hole in the tyre about an inch in diameter,
causing immediate and complete deflation - a much more severe test than the
partial deflation one is more likely to experience on the road.
In the event,
we had some trouble with the equipment, the charge first tending to fly out,
deflating the tyre without any explosion, and then exploding without bursting
the wall. But the experience of complete deflation of a front offside tyre with
the speedometer reading 105 mph was finally achieved.
I had not
feared at all for the stability of the car with a tyre burst at such high speed,
since the reputation of the Denovo has long since dispelled any doubts about it.
But I did need some reassurance about stopping, as ever with air in the tyres
the straight used at MIRA left little spare distance in which to bring the car
to rest from 100 mph, and I did not fancy an ignominious sortie into the
emergency sand bank.
The crack of
the explosion, and a momentary pall of smoke past the driving window, left one
in no doubt that the charge had gone off, but there was no pull at all on the
steering. It was not until the brakes are applied that a slight movement to the
right had be checked, but there was still no question of having to fight the
wheel or anything of that kind. On one run I tried "hands off" braking after the
deflation and the car certainly wandered to the right, but it was still only a
deviation, not a violent pull.
have been no worries about arresting the car with a flat, the stopping distance
was the same as with all tyres inflated. The only difference was that the
deflated tyre, under firm braking, left a pencil thin black line on the road. If
one has any doubts as to whether one could have a Denovo burst, remain unaware
of it, and continue driving at speed, the answer is that the 2in. drop of the
carīs attitude on the side which has deflated is remarkably noticeable. One
would have to be very insensitive as a driver not to notice this and realize
that something was wrong.
experiences one might have had second thoughts about the wisdom of ending our
Denovo tests and reverting to conventional tyres, but it should be borne in mind
that much of this carīs mileage is covered in traffic, with no opportunity for
very high speeds. If it were in use for long Continental journeys the relative
importance of Denovo safety would be much greater.
itself is now well into the third year, and the question of its replacement has
naturally been considered. As far as the driver, our managing director Tim Gold
Blyth, is concerned, replacement would only be with another 3500 S, as the model
suits him ideally in almost every way. The condition of the car is excellent,
and it seems rather doubtful whether the cost and extra depreciation involved in
replacing the Rover at this stage would be justified. So, particularly bearing
in mind, Autocarīs interest in the life and durability of the model, the
decision has been taken to retain it for at least another year. We will be
reporting again sime time after passing the 50.000-mile mark.
Autocar / UK