Dear Oil, Sorry...............All,
I've been very confused about oil to use in my Riley 9hp engine and have
had a different answer from everyone I've asked. I've been seduced by
packaging and advertising by some companies purporting to specialise in
lubricants for old cars and spent a small fortune as a result. I was
therefore heartened and reassured by the following letter inthis months "
Automobile " magazine. I hope they don't object to my quoting it here and
trust it may be of assistance.
BTW "automobile" is a must for old car enthusiasts and subscriptions are
available worldwide.
SOME HOME TRUTHS ABOUT OIL
It was good to see Steady Barker talking some sense about oil and the older
car (The
Automobile, March). That's not to say that Steady and sense are strangers,
just that there is a
lot of myth and mendacity around when it comes to oil. I was involved in
some independent
research on lubrication and engines a few years ago and turned up some
information which
may be of interest to your readers.
Cheap oil should be avoided, even if your car does suffer from heavy
consumption. To meet
industry standards cheap oil is made up using a large percentage of
inferior stock topped up
with a small quantity of superior stock, with additives. In use, the
superior portion and the
additives are quickly consumed or degraded, leaving something which has
greatly reduced
lubricant properties. Engine performance and longevity suffer, and wear
accelerates. Adding
more cheap oil does not improve matters. Unfortunately, the API grades
given to oil (and shown on the container) don't help much as they can be
overcome by clever
blending. Buy the best you can afford from a reputable company - it's
cheaper than an
engine rebuild.
On any engine running shell bearings, or that has been recently rebuilt,
you should seriously
consider using synthetic oil. Independent testing has shown that in every
respect synthetic oil
is superior to mineral oil, and often by a considerable margin. Wear
resistance, low and high
temperature protection, out of service protection, low and high speed
running are all served
better by synthetic oil. It costs more than ordinary oil but it is so much
better that the extra
expense is worthwhile.
Two other factors have a large influence on engine life, prrformance, and
protection:
efficient filtration, and adequate cooling. Steady was right to recommend a
full flow filtration
system. Older cars often have incredibly poor filtration if they have any
at all. Frequent
engine rebuilds may have been acceptable (by some) when labour was cheap
and the
industry was geared up for them, but there is no excuse now. Improved
filtration is available
for many older cars (it's one of the things my company specialises in)
without major or
expensive modifications. All engines, especially shell bearing engines,
will benefit
from it.
Oil coolers are often seen as unnecessary on anything but racing or modern
high-
performance cars. However, modern fuels, modern driving conditions, and
even modest
increases in power output can lead to overheated oil. This will lead to
accelerated engine
wear, loss of economy and power, and reduced engine lift. Overheating of
the oil is not
always obvious - water temperature may be unaffected - and few people
bother to fit an oil
temperature gauge to their cars. Wt fitted such a gauge to a mildly
modified MG Magna a
while back. When the owner was driving on a reasonably fast A-road he was
surprised to see
the temperature go, over 100"C, and over llO"C on the motorway. The ideal
running
temperature for oil should be 70-80"C (above 90"C, mineral oil's lubricant
properties are
reduced, although synthetic has a higher r,perating range). The owner then
fitted an oil cooler
and the temperature remained between 70 and 80 degrees C.
As the lubrication problems of older cars are such a minor consideration to
the large oil
companies and to consultant engineers there has been little, if any,
accurate independent
testing done on the suitability of modern oils. The problem is not helped
by niche market
products where more money is spent on developing the packaging than the
product. For
those who own old cars (as well as old car owners) choosing the right oil
is not easy, but who
said life should be easy? Steady as you go, now.
Derek Magrath,
Flexolite, Malvern, Worcestershire
Yours plagaristically, JH
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