I came across some stored treasures the other day. Amongst them were old handbooks & maintenance manuals of past owned everyday cars, including Morris Minor, Triumph Herald 12/50, Alfa Romeo Alfasud and Morris Mini cars.
Up to the early 1980's cared for engines wore out very quickly, with mediocre lives of approximately 70,000 miles. After this point, engines with much tighter clearances were introduced togeather with early electronic ignition systems. Car milages of 150,000 plus then became commonplace.
What encouraged the use of finer tolerances? after all, the technology to achieve them in mass production was probably available as far back as the 1930's. Was it the availability of better oil chemistry perhaps, (Duckhams 20/50 and BP Viscostatic were available in the early 60's) or the increasing opportunity to run at higher constant road speeds for long periods? The M1, the UK's first motorway, opened in 1959 with constant speed motoring limited to A road dual carriageways by and large until the late 1960's mid 1970's.
It could'nt possibly be the influence of a cynical motor industry - could it?
Put me right,
Regards,
Julian
|
Dunno, but I guess its what ever becomes the critical bit.
In those days, even with 70k engines, half the time the body gave out first through rust. Or the interior, or the appearance.
My earlier cars all died through body-work failure, rather than engine failure, and I always drove seriously high mileage, knackered cars through total lack of money for anything else.
Still what do I know, I had a Mk1 Beta and when it rusted away I bought a MkII, so obviously I don't learn very well.
I would guess that everytime something improves, something else becomes the limiting factor for a car's life and in turn receive attention.
Also, I think the reasons for changing cars used to be different; Plastic seats to cloth seats, drums to discs, pushrod to OHC - quite major improvements, even to the non-tech minded.
Changes from belt to chain, ECU, Direct Rail, etc. are not so obvious.
|
The first motorway was not the M1 but the section of the M6 the Preston bypass
which I travelled on its openigday with my father in a 1949 Austin 16 and managed to get to 85 mph.
It is true to say better oils have made for longer lasting engines along with computor controlled production and better quality metals just a natural process of improvement as is found in all enginered products.
|
|
|
|
An old geezer who worked for BMC in the fifties told me that the engine and gearbox of a Morris Minor were designed to last no more than 45,000 miles. And that's exactlyn how long they lasted on my dad's November 1956 Minor 1000, which was a working car, bought new, not a cherished classic.
HJ
|
There's the trick. The design life is set by the manufacturer, and many consumer items are built to a cost. A longer design life will ususally (but not necessarily) incur higher development costs and more expensive materials and manufacturing processes. If you add materials & technological advances, robotic assembly techniques and higher (manufacturing) volumes you can get longer design life for less cost.
Martin.
|
|
|
We did much more mending, but at least it could be done. Exhaust valves on an Austin 8 (driven mostly on full noise, such as it was, to get along at all) lasted 4,000 miles but could be replaced at home, even by me. (The rust bug got at it, eventually, and I had to have help.)
Plenty of people did such as crankshaft out jobs.
|
|
|
|
Well with some brands it depended on how they were cared for I think...My Dad Bought a M-Benz 250 SE in june of 1967 new at the factory When I sold it in 1993 (Sill Rot killed it at last)it had done 235,000 miles with only a top overhaul at 140,000 Oil and filters were chainged every 3000 miles and all multituse of grease points (including the funny cone shaped wones on the doors) were also done every 3000 miles
Pinion whine from the limited slip rear end showed up at about 120,000 miles and we learned to live with it as by then it was my car... id did not affect the working of the limited slip and a proper choice of the music from the Radio (which had short wave on it so I could listen to the BBC world service) covered it quite well... when it was sold as a parts car to someone who was restoring a 67 250SE Convertable he remarked on the fine condition of the Green leather interior (sadlesoaped by me each month then given conely leather food treatment) and how he planed to use all it in his cabro whose leather was badly rotted
~R
|
|
|
I don't think you can generalise about engines. Some old cars were famous for big mileages. eg Rolls Royce Silver Ghosts built for the first world war still in service in the second, Land-Rover petrol models,etc. Volvo Amazons do collosal mileages -a million is not unknown. I'm sure everyone can think of other examples.
My 1964 Triumph 2000 has done 82,000 and runs perfectly and silently, no oil burning, clean exhaust, etc.I don't regard it as a high mileage - just run in, in fact.
I think what has happened is that the technology to make long-lasting engines has been around since 1914, but it was only applied to quality cars. Modern production methods now make it applicable to cheaper models too.
|
Cliff, you're right. Everything is much better made now. Take a look at a yoghurt carton and how fantastically perfect it is. With the right tools and materials you could probably make one that good. But try making ten thousand a day to those kinds of tolerances.
Chris
|
|
|
"My two Triumphs, a 1965 2000 and a 1972 2500, each reached 170,000 miles before significant trouble arose
(piston/ring wear in both cases). I feel sure that this was helped by the fact that I changed the oil at half the
specified intervals. In each case the crankshaft and bearings were still serviceable, though I fitted a new
crankshaft in the 2500. I kept the filter changes to the recommended mileage however, since a part-used
filter should provide slightly finer filtration than a new one."
Interesting point about the oil filter. I would never have thought of. I agree entirely about changes - I have always changed oil at 3000 miles and the filter every 6,000, ie with alternate oil changes. My reasoning was that with more frequent oil changes the filter would not have picked up so much so it was a bit of a waste renewing it. But your point makes good sense too David.
Another thing about older engines is they seemed often to have poor engine breathing/ventilation, so a lot of old gunge accumulates in the rocker cover. Attention to the pipes and breather holes, possibly enlargement, seems to improve this.
|
|
|
|
I'm sure the improvement in engine life was largely down to 'customer demand'. However, we may have reached the pinnacle since fleet buyers demands for extended service intervals are likely to result in shorter engine life -- unless the engine has a very large oil capacity as recently mentioned in this forum in respect of the Mercedes C240 for example (8 litres, I think).
My two Triumphs, a 1965 2000 and a 1972 2500, each reached 170,000 miles before significant trouble arose (piston/ring wear in both cases). I feel sure that this was helped by the fact that I changed the oil at half the specified intervals. In each case the crankshaft and bearings were still serviceable, though I fitted a new crankshaft in the 2500. I kept the filter changes to the recommended mileage however, since a part-used filter should provide slightly finer filtration than a new one.
|
>>I'm sure the improvement in engine life was largely down to 'customer demand'. However, we may have reached the pinnacle since fleet buyers demands for extended service intervals are likely to result in shorter engine life.......
I think you are right there David.
It is my contention if you wished to buy a car now for some very long term "beat the system" ownership it would be better to go back to something from around 1990 with no ECU/Air-Con/ABS/EFI/Cat etc.
Take the BX or Golf as an example. Get a 1990 petrol (around 90,000mls) that has had a decent life and you will have something that will go another ten years without much rust, the engine will last another 70,000mls+ with frequent oil changes.
Any car much older than this (1980s or earlier) will likely have an engine that will give up much sooner and suffer terminal rust.
Something much newer is likely to be a challenge to keep going as the expensive electronic/safety related items fail. Also as you mention we might start to see expensive repairs needed to engines for these daft extended service intervals.
David
|
|
|
|
