why oil motor to be black ?

Answer 1

Depending on the previous oil changes and how many miles the vehicle has on it, even though you just put fresh oil and new oil filter on the car and you check the dipstick and the oil is still black, this is common. Consider the fact that when you change the oil, you are not getting all of it out..sometimes there is a lot of build up of burnt deposits in the cylinder heads and lots of sludge left in the bottom of the oil pan, of which changing the oil, will not remove any of this...If your car has high mileage you may not ever see clean oil on a dip stick..even though black, doesn't mean that it has broken down, just means that you may need to change it, more often, but i would suggest that you put a BG engine cleaner in the oil, and run it at 3k rpms for about 15 minutes before each oil change...this will remove the build up and help you remove it without having to pay repair shop xxxamount of dollars to do it..

Answer 2

Numerous reasons. The most common reason is simple normal burning if gasoline. Some of the gas gets into the oil and it turns it black. You should not judge the quality of the motor oil by it's color. Motor oil is designed to hold particulates of carbon so being black means nothing. Most cars need an oil change between 3,000 and 5,000 miles. Or just change your oil once every half year if you seldom drive it. I own an auto shop, I speak from educationa nd practice. Good luck.

Answer 3

Diesel engine oil will get black, but if you have a gasoline engine you really need an oil change.

Answer 4

Ditto on what scion_xb_girly said, not only should you change it, change your oil filter too.

Answer 5

umm, if your oil is black, good time to change it

Answer 6

ITS PARTIALLY BURNED! HAS RESIDUE FROM BURNING GAS IN IT