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I don't doubt that; I was referring only to the temperature gauges. Would the low cold viscosity of Mobil 1 have any bearing on it too? That is, if it circulates more freely then presumably it warms up more quickly.
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Given that it takes 7 miles for an engine to warm, and longer for oil to fully warm up, how long does it take (given fairly average British weather conditions) for an engine to cool down?
(I ask because I know that short journeys from cold are a bad thing for engine life, but I will often do several shortish journeys in a day, with the engine not really getting a chance to fully cool down - the car might sit for, say, an hour or two between journeys.)
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Given that it takes 7 miles for an engine to warm, and longer for oil to fully warm up, how long does it take (given fairly average British weather conditions) for an engine to cool down?
It takes about half an hour for my engine to cool down enough so that I don't burn my hand on the exhaust manifold when I unscrew the oil filter.
The oil is still warm and substantially thinner than when cold, after about an hour.
Gently falling snow still melts on the bonnet at least 2 hours later.
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Very interesting thread.
I generally give a car about 6 miles to fully warm up in summer, and upto 10 miles in winter, depending on air temperature.
Incidentally, I understand diesels take longer to warm up than petrols, I believe this is because they are more thermally efficient? Our Focus TDCi can take an age to warm up in winter, I have often pondered if there is a fault with the thermostat, because on cold winter mornings it often takes 7-8 miles before the temperature needle reaches the mid-point (and that, I believe, is a long time before the engine components and oil reach optimum operating temperature). This is despite not using the heater for at least 3 miles from start-up. I have found that this engine needs some load on it before it will warm up; I haven't found this with petrol vehicles, they tend to warm up quite quickly however they are driven. As such, after about three miles I tend to make the engine 'work' a bit; not to the extent of full load acceleration or very high revs, but this makes it warm up faster than if I tootle along. I believe it is important not rev or place high loads on a cold engine, but I also think it is important to get an engine upto temperature reasonably quickly. If I take an 'alternate' route from my house, I encounter a long but gentle hill after about 1-2 miles, and this makes the engine warm up much faster than if I travel in the opposite direction, despite the fact the other direction is not downhill, but relatively flat.
My 2p worth
Regards
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I have found engines hold significant heat for, as you suggested, about 2hrs, but it retains *some* heat for about 4hrs.
Regards
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Reading from the Perkins Prima operators handbook which is the diesel engine which powered the Montego and Maestro. It was also a favourite marine engine for the yachting fraternity.
?A gradual running in of a new engine or a POWER EXCHANGE engine is not necessary. Prolonged operation at light loads during the early life of the engine is not recommended.
Maximum load can be applied to a new engine as soon as the engine is put into service and the coolant temperature has reached a minimum of 60c (140f).
CAUTION.. Do not operate the engine at high speeds without a load.?
This is in line with the large electric generator engine a Gardner which we had as an emergency electric supply to our establishment.
The instructions for use of this equipment was that full loading was to be placed upon the engine immediately after start-up. Conversely when the generator was disconnected from the mains it was then to be allowed 20 minutes running to cool down.
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This is definately an interesting read.
To the writer who leaves his heater off to let the engine warm up: I do the same too! I just hope I can buy my next car from someone who understands engines and doesn't take the pap written in the manual as gospel.
It's good to know I'm basically doing the right thing, as while I like to think I have a very good understanding of engines (Well, better than your average person), I'm hopeless with a toolkit. I have dabbled, like taking the alternator out etc, but oil and filter changes, spark plugs, air filter, basics like that are unfortunately my limit.
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So in view of the above, if for various reasons you can't walk the mile and a bit to work and you take the car five days a week there and back,is it wise to go the long way round by adding 7 or 8 miles to your trip each way or at the end of the day, in the general scheme of things etc. etc. does it make a material difference? i.e. if you only do this kind of mileage(kilometerage?) your engine might not last for 250,000 miles but surely you could get a lot of journeys in before the wheels fall off? And will an Italian tune up once a month put it all right.
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The more an engine runs at full operating temperature, the happier and longer lived it will be. So, yes, if the drive to work is unavoidable, go the long way around. And, yes, regular Italian tune-ups should also be beneficial.
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I don't get the bit about going the long way round.
If most wear occurs when the engine is cool, it doesn't mean that once it has warmed up the process is reversed!
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I don't get the bit about going the long way round. If most wear occurs when the engine is cool, it doesn't mean that once it has warmed up the process is reversed!
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The wear isn't reversed, but the damage to the oil is. Oil that has been contaminated with low-temperature condensation of combustion products and petrol is "cleaned" by evaporation when it warms up properly.
Similarly deposits in the combustion chamber will be burnt off at full operating temperature.
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I'm afraid I didn't make myself very clear; I don't ever take 'the long way round' to a destination, but occasionally I travel in the other direction through necessity, and it is on these occasions that I have noticed the above difference. Apologies for the confusion.
Back on topic, I have always been intruiged by the level of amazement people have shown towards Mobil's 1 million mile BMW. I don't doubt the claim it is probably one of the best oils in the world (hence why it is in our cars), but surely a test such as this is not representative of 'real-world' conditons of stop start traffic and cold starts etc. I'm confident just about any engine, with occasional oil changes, would, under the same operating conditions (i.e. always warm) be able to complete far in excess of 1 million miles. Would anyone agree?
Regards
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What BMW do you mean?
Although I agree with you 100% - christ, my mates old micra made it too 100,000 and that thing had the living pink fluffy dice kicked out of it - booted from cold, handbraked round the college carpark everyday, run with the oil light glowing away...
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A quick search for 'Mobil 1 1 million mile BMW' threw up the following from the Mobil 1 website:
{The 1-million-mile test involved a car on an outdoor dynamometer running through a start-stop, low-speed/high-speed protocol more or less 24 hours a day. Oil drain intervals were 7,500 miles, the maximum specified by the vehicle manufacturer. At the end of the test, with 1,001,120 miles on the vehicle, the engine was removed and disassembled. Overall engine wear was extremely light. In fact, with the exception of light-to-moderate wear on the camshaft and followers, no other significant engine wear was noted. And oil consumption over the entire test was just .040 quarts per 1,000 miles. So, how long will an engine last until it fails on Mobil 1? It's safe to say that no one knows!}
As you rightly point out, any car will last the distance with the most basic of care, I should expect that those that fail below 100,000 miles have either not been serviced frequently enough or have been driven unsympathetically. I have no doubt that my cars will out last the time that they are under my ownership (And as such will benefit the next owner far more than me), but I feel happier knowing it is operating under favourable conditions, especially when I am giving it a work-out.
Regards
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Achieving a million miles is not difficult, in ordinary driving conditions, as long as the oil is changed regularly and the car is serviced properly.
I know of Irv Gordon, the 2 million mile Volvo P1800 man, and several 1 million mile plus Volvo Amazons in South Africa. One was prepared for a rally in 1960 something, and used daily ever since.
I recently heard of a Swedish taxi driver who retired his elderly 740 after 800,000 miles, and passed it on to his son to use as the family car.
The reason most cars don't reach those figures is
1) they aren't serviced properly
2) they fall apart from rust before they get there.
3) they aren't economically worthwhile keeping
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HJ reported on the million-mile BMW in the Telegraph in the mid-late 1990s, I think (I still have the clipping somewhere). It certainly caught my attention and woke me up to the longevity of well maintained modern cars and the crucial role of oil. Thirty years ago you got shot of a car by 50k for fear of rapid deterioration and horrendous expense; by the 1990s those folk memories were still lingering.
I agree with others who imply that it is more about regular maintenance and frequent oil changes than about BMWs per se. Irv Gordon's checklist in HJ's FAQ is well worth reading and heeding:
www.honestjohn.co.uk/faq/faq.htm?id=34
Having kept my Audi 100 for ten years, I'm now increasingly sure that the twenty-year life of my Capri 2.8i may be exceeded by my other cars (ninth birthdays this year). Even with a lottery win, I'm not sure that I'd change them, although I could well warm to a 1962 Ferrari 250GTE 2+2 as a fourth indulgence.
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I agree Roger. But you have a long way to go still with your Capri - my Triumph 2000 has been in daily use for 40 years. My 93 Volvo now has 311,000 miles.
I agree there has been some improvement in build technology, but mostly I suspect it is simply that people are more aware now of how to treat a car properly. Remember the way everybody idled their cars on the choke until they had warmed up? Gave the engine a nice satisfying roar as soon as it had fired? Struggled on with worn out spark plugs, trying to clean them with sandpaper?
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Agree with Cliff; a well designed engine should last at least 200,000 miles with an annual oil change. E.G. local minicab firm with 450,000 on Sierra, minicab driver`s delight! Who ever wore out a Pinto engine? Practically impossible. I think all this stuff about 5000 mile oil changes is too romantic, unless you have an engine with components over stressed due to poor design or over-development (e.g. Rover V8 camshafts - lobes about the same size as a BMC "A" series in Grannie`s old Morris Minor).
Have always found thrashing a good thing to loosen an engine up; e.g. 1964 Minivan cruised at 80, flat out, no problems oil consumption, did 80,000 in late `60`s; BUT (then new) 1963 1275 Cooper "S" would cook the oil at 80 mph cruisein 5 minutes, oil pressure drops etc. Carry on like that and a replacement engine your happy fate at 20,000 miles. Not the engine it`s original designer intended.
So it all depends.
Doubt if most modern engines would be that feeble or over-stressed, my worry would be manufacturers cost cutting on key components, particularly French cars, where excessive labour costs plus high social charges make these well conceived designs a high mileage nightmare. Is Germany going the same way?
AS
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"manufacturers cost cutting on key components, particularly French cars, where excessive labour costs plus high social charges make these well conceived designs a high mileage nightmare"
Really?? There are a fair few PSA XUD engines around that might disagree with you. My last two did 170k and 140 k without a spanner being laid on either engine except for cambelt and glowplug changes. When last heard of the 170k one had done over 200k and still going strong.
Below is a post from someone else which I have used before to illustrate the longevity of PSA diesels.
Posted by Mike 1703 on September 24, 2002, 12:58 pm , in reply to "Perfect car?"
194.117.133.84
I drive a BX diesel which I use as a taxi. It's my 5th. BX 19 diesel & all gave me the greatest satisfaction in both reliability & economy. I still have my 1987 BX which I cannibalise for spares, not that I need many. It was retired for 'scrap' after a crash @ 350,000 miles. It's replacement was sold off for less than the value of its parts @ 450,000 miles; one has been retired to my driveway @ 740,000miles & my current workhorse is now @ 380,000 miles. I've never changed a wheel-bearing, only one gearbox and a few suspension bits; one major engine overhaul; two head-jobs but never a tow-home failure [unless you count the one time I let the cam-belt snap!].
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