could be oil burn off from the leak Or during repair, the relative dripped oil on the motor, and the excess is burning off when the motor gets hot!
Onto your driveway.
Last resort, if the oil and tar won't come off with regular cleaning brush, you can use a pressure washer surface cleaner from bestcargurus along with your pressure washer, that will surely do the job.
the best way to get paint off your driveway would be mineral turpentine.
A great way to get motor oil off your hands is to use olive oil: Squirt some olive oil on your hands, rub your hands together to get the motor oil dissolved, then use soap to remove the mixture. Works great, doesn't leave your skin dry and irritated like solvents do.
If the motor is healthy, the oil will burn off in a moment or two.
you have to pull the motor and when you get the motor pulled take the oil pan off and the oil pump is in there ity will have a tube with a screen on it good luck
purple power or any degreaser
you will have to raise the motor up by taking the motor loose at the mounts just enough to get the oil pan off.
One way to remove oil stays off cement driveway is by pressure washing it. You however have to use the correct pressure washing attachment to avoid damage, so it is best to use a pressure washer surface cleaner from bestcargurus, not will it only remove the stain faster but it will also ensure that you wont damage your driveway
decreased temperature
You have to hoist the motor up just enough to get it off take the motor mount nuts off there is a filter inside the oil pan tht is holding it