Thread: Delvac 1 Help
View Single Post
Old 02-19-2004, 12:02 AM
ericnguyen ericnguyen is offline
Registered User
Join Date: Jan 2003
Location: USA
Posts: 699
The main reason why fresh oil becomes dark very quickly is because about 1 quart of OLD dirty oil stays in the oil cooler lines and the oil cooler (located next to the radiator). The soot and sludge in this 1 quart of old oil are enough to make your new oil turn black very quickly after starting and driving for a short distance (several miles). Some of the leftover oil in the bottom of your oil sump also adds soot and sludge to the new oil.

A regular oil change (either by removing the oil sump's drain plug or by sucking through the oil dipstick tube by a topsider) does not remove the old dirty oil in the oil cooler lines and the oil cooler. I have found that the topsider method actually removes more dirty oil from your oil sump than the conventional drain plug method (not a single drop of old oil dripping from the drain plug hole after just several minutes of sucking). When I change oil (be sure that the oil is HOT and HOT), I park the car with its front downward on an inclined driveway, or jack up the car's rear if it's on a level surface. Next, I use a Mityvac oil pump to suck out the old oil through the oil dipstick tube. It takes only 5 minutes to do a pretty thorough oil change, and everything stays clean without a mess.

BTW, don't attempt to remove the oil cooler lines with the intention to completely remove the old oil. It's a pain to remove these things, and you will also create a whole mess of spilled dirty oil on your driveway or garage floor. Time is precious, so do not waste your time for being paranoid about how to remove all the old oil to prepare for a new oil change.

Reply With Quote