Black Oil - Is It A Problem?

[jumbojake]

I've recently done my first oil change on my 2004 Avensis D-4D since I bought it a few months ago.

After just a few hundred miles I noticed the oil is already black.

My previous car (18 yeard old petrol Renault) would last near the next service before the oil changed colour...

So .. is this normal for a diesel... or is mine telling me of an uncaring previous owner?

[t-spiritpete]

I've recently done my first oil change on my 2004 Avensis D-4D since I bought it a few months ago.

After just a few hundred miles I noticed the oil is already black.

My previous car (18 yeard old petrol Renault) would last near the next service before the oil changed colour...

So .. is this normal for a diesel... or is mine telling me of an uncaring previous owner?

Hi mate, this is quite normal with most diesel engines due to the type of oil used which holds a lot of the carbon produced suspended in the oil, also there is a reaction between some oils and the cast iron engine parts, the later all alloy engines don't have this problem. If the engine is quite high mileage there will be the black residue in the engine block and sump so it will mix with the new oil and go black very quickly, some would say use a flushing oil or agent but in my opinion with a high mileage engine this "may" disturb the sludge and block up oil galleries which can lead to engine failure, as I say just an opinion. For peace of mind you could always change the oil and filter again after a couple of thousand miles when the engine is really hot as the oil will be very thin and this will get more out, just be very careful with the hot oil.

Best regards .... Pete.

[acetip]

I've recently done my first oil change on my 2004 Avensis D-4D since I bought it a few months ago.

After just a few hundred miles I noticed the oil is already black.

My previous car (18 yeard old petrol Renault) would last near the next service before the oil changed colour...

So .. is this normal for a diesel... or is mine telling me of an uncaring previous owner?

Hi mate, this is quite normal with most diesel engines due to the type of oil used which holds a lot of the carbon produced suspended in the oil, also there is a reaction between some oils and the cast iron engine parts, the later all alloy engines don't have this problem. If the engine is quite high mileage there will be the black residue in the engine block and sump so it will mix with the new oil and go black very quickly, some would say use a flushing oil or agent but in my opinion with a high mileage engine this "may" disturb the sludge and block up oil galleries which can lead to engine failure, as I say just an opinion. For peace of mind you could always change the oil and filter again after a couple of thousand miles when the engine is really hot as the oil will be very thin and this will get more out, just be very careful with the hot oil.

Best regards .... Pete.

hi

ive never been a great beleaver of using flushing oil.

when a car engine is first filled with oil at the factory this is called the initial fill and the quantety is used to be shown in official works sevice manuels for the vehicle,but you will not find it in haynes books.

the point is that the intial fill is greater than the oil you will drain off at oil and filter change as much as

a couple of pints on larger engines meaning oil is trapped in oilways and gallarys in the engine.

no real problem there. but flushing oil is a detergent not a lubrication oil.

so when you finished flushing and drain out this detergent your leaviing some behind in your engine to contaminate

the lubricating oil your putting in.

not good practice.