black oil after less than 500 miles?!??

[rtlarson]

I figure my cutty has 122K on it.. I say that cause the engine bay looks pretty much untouched and there are no leaks anywhere and the break pedal has little wear on it. It makes no rod knock or rocker noise or anything, its really quiet except for something on the pully system is about to go out (im thinking smog pump since the ac is already bypassed.

anyway i got the car from volunteers of america for $900 and the oil was blacker then Wesley Snipes. so i changed it when i gave it an (almost) complete tune up. i checked it a couple weeks later and it was black again!! I've never seen that happen before. is it a sign something bad is going to happen??? It is having some running issues but we'll talk about that after i get a new cat on it cause im pretty sure thats the prob

 

[megaladon6]

for a high mileage engine it's pretty normal. do NOT do an engine flush!!!!! that will kill the motor. you can put a qt of ATF in there and change the oil after about 500mil, but you'd have to do it repetitively, and i don't know if it's make a real change in color.

 

[RITTER]

Yeah, just carbon build up inside your engine, nothing to worry about

 

[bigdan]

the fact that the engine wasnt maintained ..... it will take some oil changes before you notice that it takes time before it gets contaminated

 

[pontiacgp]

I agree with bigdan...and also when changing oil are you warming up the engine before you remove the drain plug?...

 

[2fit661ca]

My 89 S-10 Blazer (4.3L TBI) turns the oil black after 2 days, but she runs fine, apart from all the emission crap going out with in a week of each other. It's got 166K on it. I started using Castrol GTX High Mileage on it, and that seemed to help clean it out pretty well at each oil change ...all things considered or course... a friend of mine ran 40weight through his 307 (now mine) for about 200 miles to clean it out, it worked pretty well to, though i don't know how that will treat your engine running on such a heavy oil.

 

[3rdgentug]

the 1 qt of atf works wonders!
ive been doing it for years when i get a new vehical.
do an oil change and substitute 1 qt with atf, change the oil after adriving a few weeks, he says 500 miles sounds good to me .
the detergent in the atf will clean alot of the builtup garbage out of the system.

 

[DRIVEN]

Black oil means that it has dirt/carbon suspended in it. That's not necessarily bad. That means the oil is doing it's job. If it is thin and smells like gas - you may want to investigate further. Dirty air filter, ruptured fuel pump, defective choke or float, etc. Also, different oil brands look "cleaner" longer.

 

[rtlarson]

I agree with bigdan...and also when changing oil are you warming up the engine before you remove the drain plug?...

Yeah, i have to drive 26 miles up to my friends house to work on it cause i live in a frickin condo and cant do anything here. Also, after i drained it all i cranked the engine over a few times and then dumped a qt throught it with the plug still off to try and make sure i got it all. the oil was really bad..

the 1 qt of atf works wonders!
ive been doing it for years when i get a new vehical.
do an oil change and substitute 1 qt with atf, change the oil after adriving a few weeks, he says 500 miles sounds good to me .
the detergent in the atf will clean alot of the builtup garbage out of the system.

Makes sense.. I do that next oil change.

Black oil means that it has dirt/carbon suspended in it. That's not necessarily bad. That means the oil is doing it's job. If it is thin and smells like gas - you may want to investigate further. Dirty air filter, ruptured fuel pump, defective choke or float, etc. Also, different oil brands look "cleaner" longer.

No its normal consistency and doesnt smell like gas at all, even tho its runnin pig rich.

 

[bigdan]

ATF detergent does good in a relatively maintained engine .....

only possile drawback is that it could be too much too fast .....
if rings are clogged, it might free up all the gum . you want the rings land on the pistons to clean up themselves ....ATF will do it , but i`m a little concern that it might be too fast ...maybe your oil was just plain due for a change and then any detergent agent ( rislone or other ) even ATF might do it ...

I once did the ATF treatment and the engine started to smoke after .....
but most of the time it<s ok !