Ren
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Registered: 16th Oct 04
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Mike
Organiser: North West and North Wales
Premium Member
Registered: 20th May 06
Location: nr. Skipton, North Yorkshire
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quote:
Originally posted by sand-eel
I think i'll just leave this 
It's just that a long journey car will always go through what a short car journey will do every time.
Yes, but it's how often both cars go through that that matters.
I see where you're coming from now, you're looking at it as 20 miles from cold will do more damage than 2 miles from cold and yes you're absolutely spot on.
Where people say that long journeys are better than short journeys, best example has gotta be sales rep vs. oap. The sales rep's car will be on 100k, the oap's on 40k but the Sales rep leaves his house on a morning and is driving round all day so his car gets upto temperature and pretty much stays there all day till he gets home that night. Now in that day he could've done 200 miles so lets say it takes 2 miles to warm up he's done 198 miles at normal operating temperature.
Now over to the oap. Leaves the house in the morning to go shopping. 2 miles down the road, car's upto temp but he's arrived at the supermarket and he's turning it off. While he's shopping he's feeling a bit peckish so nips into the cafe for some breakfast, all this time the car's colling back down.
Breakfast over it's back on the road another 2 miles to go to Joyce's for a quick fumble  Again car just gets upto temp he turns it off again. It cools down again whilst he's getting his oats then it's off back home so that's another 4 miles, 2 of which it's warming back up again. Day over.
So Sales rep drove 200 miles, 198 of which were at normal operating temp, OAP did a measly 8 miles but only 2 at normal operating temp.
We then find out that the OAP has had his car a whole while longer than the sales rep and he's clocked up 50k, the sales rep has managed 100k.
So 99% of the sales rep's 100k was at normal operating temp, the OAP on the other hand only 25% of the OAP's miles where actually driven at normal operating temp so 99k + 1k warming up vs 12.5k +37.5k warming up
Overall then that's 1k of higher engine wear on the long journeys vs 37.5k of higher engine wear on the short journeys.
And that's the point I was trying to put across 
And now I'll breathe out, I never expected that to be quite so detailed at the start it just managed to build up and I'd wrote too much to delete it 
I'm now going to bed before my head implodes and please, if you still don't understand it, please don't tell me or I WILL cry after the effort I've put in
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Mike
Organiser: North West and North Wales
Premium Member
Registered: 20th May 06
Location: nr. Skipton, North Yorkshire
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Ren you bastard 
Do you realise how long it took me to type all that
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sand-eel
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Registered: 15th Mar 07
Location: carluke/braidwood--IRNBRULAND
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I under stand completely now
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sand-eel
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Registered: 15th Mar 07
Location: carluke/braidwood--IRNBRULAND
User status: Offline
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quote:
Originally posted by Mike B
Ren you bastard
Do you realise how long it took me to type all that
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Mike
Organiser: North West and North Wales
Premium Member
Registered: 20th May 06
Location: nr. Skipton, North Yorkshire
User status: Offline
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I had fun tbh, it just seemed to spiral out of control and get longer and more technical the more I typed, it's amazing the shit I come up with when I'm tired
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Ren
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Registered: 16th Oct 04
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moka
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Registered: 11th Mar 06
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i have a 1 litre corsa and it never hits 90 unless im stuck in traffic for over 15mins...
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John
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Registered: 30th Jun 03
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I'd have the 50k oap car instead of the 100k rep one.
quote:
Originally posted by moka
i have a 1 litre corsa and it never hits 90 unless im stuck in traffic for over 15mins...
That's coolant temp, nothing to do with oil temp.
[Edited on 26-02-2009 by John]
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johnhara1
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Registered: 19th Oct 06
Location: Newcastle upon Tyne
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Apart from engine wear, you also have more drive train wear on cars that only go to the shops and back rather than these mile munchers on the motorway.
The constant stopping and starting, bumpy local roads, hill starts and well lots of corners means the car that just pops round the shops daily will prob have worn CV's, clutch, brakes, handbrake, suspension etc even though it has done half the milage.
High milage shouldnt put people off IMO, just inspect the car thoroughly. Also you can tell alot about the car from it's owner i think.
[Edited on 26-02-2009 by johnhara1]
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John
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Registered: 30th Jun 03
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The 100k mile car has the mileage to wear the components though.
The 50k one will be worth more and have a better condition interior.
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johnhara1
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Registered: 19th Oct 06
Location: Newcastle upon Tyne
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quote:
Originally posted by John
The 100k mile car has the mileage to wear the components though.
The 50k one will be worth more and have a better condition interior.
Interior bit is true, but i disagree about the drivetrain wear if it's just been up and down the smooth motorways.
Clutch yeah but not much else will bet abused as much as the car that bumps along the back streets to the shops everyday.
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John
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Registered: 30th Jun 03
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I know what you mean, girlfriend had an R reg corsa with under 30k miles up until last year, bits were starting to need replaced because it just sat there, engine was fine though, in a modern engine, ie from the last 15 years, the short journeys won't be making much of a difference imo, i'd rather have the low mileage one.
I know there are new downfalls to short mileage like dpf's before anybody says.
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Corsa_Sport21
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Registered: 13th Apr 08
Location: Leven, Fife. Drives : 205 GTi
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My car is upto full temp in less than a mile.And thats going by the book recomended temp(b4 opening it up) and what it reads on the MFA.
I also beleive that engines should be given a good roasting from time to time and not just driven like a granny everywhere.
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sand-eel
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Registered: 15th Mar 07
Location: carluke/braidwood--IRNBRULAND
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I agree, engines seem better if given a good roast from time to time. Weirdly enough my silver corsas emissions have gone down every year since I got it.
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sand-eel
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Registered: 15th Mar 07
Location: carluke/braidwood--IRNBRULAND
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^^^ proven by MOT test
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DizzyRebel
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Registered: 2nd Jan 09
Location: Lincoln
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Its nothing to do with engine operating temperatures, thats what multigrade oils are for. The idea is they protect from cold and are still sheer stable at high temps and speeds, modern oil technology has come a long way and 90% of the good oils out there protect engines from wear just as well from cold as they do when up to temperature.
High mileage motorway engines will always have more wear on them than low milage short journey engines. The piston rings on a high mileage engine are still working as hard through towns but they are doing the extra motorway miles that the town shopper isnt.
The extra wear comes from how hard you drive it.
If motorway driver is a very careful man who never revs his car above 3k then engine wear will be minimal, but over a long period of time it will still happen.
If town shopping grandma is a bit of a street racer and revs her car to the redline all the time in every gear to the shops and back, shes putting far more stress on all the load bearing components so we can safely say this engine will be at least as worn was the motorway engine.
Now heres the controversial part: the engine that was thrashed from day 1 will be MORE powerful than the careful motorway driver. Why? Well the piston ring seal in the thrashed engine will be much better due to the extra force exerted on the rings during the bedding in period means the surfaces mated much better. On the low revved engine the piston rings wouldnt have sealed properlyon bed in and gaps in the seal would have formed - this will result in ring blow by and a loss of power as well as oil contamination.
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DaveyLC
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Registered: 8th Oct 08
Location: Berkshire
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quote:
Originally posted by sand-eel
^^^ proven by MOT test
Emissions are only down because the cat is warmed up to optimum opperating temperature.
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Ellis
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Registered: 11th Sep 07
Location: Aberdeenshire
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I just start my car 5-10 mins before I use it in the morning, that way oil is pretty close to operating temp...
Engine has now done 100k nearly and doesn't burn any oil at all 
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