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I put the same oil in both my car and the wife's
The wife has driven about 3miles a day since last August
and the oil still looks like its in the can
Last Saturday I did a oil and filter change on my car then on Sunday
I drove to stoneliegh and back,200 miles and my oil is black

Why does oil turn black ?

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Oil turns black for a number of reasons. In an older car perhaps the quickest thing turning the oil black is picking up contaminants that are in the engine already. New contamination is primarily carbon from combustion and coking of oil. A very minor component is extremely fine metal particles, but this is never enough to colour the oil if it is changed. The oil in a gearbox would have some metallic contamination, but it rarely is black on draining.

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Agreed, all the engines I have taken apart (except those I know have been rebuilt etc) have had an unhealthy layer of tar-like oil in the sump. I guess this contaminates the fresh oil pretty fast.
If you are bothered, as above drop the sump and clean it out. I don't think I would be inclined to use an oil flush additive, it may spread the crud around the engine. Otherwise leave until you need to drop the sump.

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also  blow by will effect the stuff.
And also how hot your oil got.

what oil did ye put in,!!!  a moer moder oil,!!  if so,it will be softening alsorts up,so making your new oil dirtier faster.
older oils did no keep the dirty stuff in suspension,  so it settles in the sump.
thats why as Clive says,its tick in there, some times 12 an inch tick
the older type filter did no like it ,so thats why oil had not the dispersants in it

modern oils have alot of didpersants,and the filters are diff to, so the stuff is carried into filter,and held there.

take a filter to bits, and its like  gooey tar in there.
so istead of being int sump,its int filter.


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I use a 20/50 oil cant remember the make,it's just whatever the local macces have on special
my local Carspares don't stock it so i buy a couple of 5 ltr cans when I go to macces every so often.

I don't have any rattley ends and my pressure is quite good
Can the sump be dropped and the shells changed with the engine in situ,if I decide to do the shells that is
It's a 1500 in a herald ?

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Shells can be done with the engine in, but it will probably need jacking up a bit, which probably means the rad needs either hoses off OR unbolt the rad so it lifts with the engine.
Best to wait until you have checked the bearing size if you plane to fit new bearings. Possibly std size, but could be anything.

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A job for the warmer weather
Drop sump,check shell size,order shells,clean sump then fit new shells
and return sump to its home
And if I can get my unleaded head skimmed I could fit that at the same time

If the heads off and the bottom dropped I could then fit a new cam and,
Hang on I only asked why has my oil has gone black ! ;D

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If you wish to know more about oils, can't recommend this book enough:
http://www.veloce.co.uk/shop/products/productDetail.php?prod_id=V4365&prod_group=Performance Tuning & Modification&

Sorry, doesn't link directly, but go there and search for "Which Oil?"

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