Dirty Oil

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I have a new oil pump, new screen and I throughly cleaned out the pan. Why is my oil always black; even right after a change?
 
might have to do with your oil type
are you using dino, or synth?

what's the condition of the engine? is it burning any oil at all?
 
That's blowby- combustion chamber byproducts getting past the rings and into the oil. Have you done a compression test recently? DOing a dry test and then a wet test will give you a better idea of how worn your rings are.
 
I got a new engine with about 300 miles on it and it still barely shows some "amber" to the oil color. the blackness is from dirt, blowby, carbon, etc. on an older engine you might be cleaning out some of the old dino oil with the newer detergant based stuff. I know my old 170 lost some oil pressure the first year I drove it but seemed to rev better and stabalized at the same spot after that year for the next 3 (until I pulled it for a 200 and t5) the oil getting dirty means things are working correctly. only get scared if it has a metallic look to it..
 
If the pan was dirty so is the rest of the engine, and the detergents are picking up the dirt and carrying it out. I wouldn't worry much as long as the engine runs good and holds oil pressure, the filter will catch any particles big enough to do damage.
Joe
 
I use standard 10W40; my oil pressure is always good, but I am burning. I also get black smoke on acceleration out of first gear...
 
Burning oil, black smoke on acceleration and a large sooty mess on the ground as it starts...

How much of this is a result of worn rings?
 
my 'stang left a whole buttload (and yes, that is a scientific measurement) of soot like stuff on the ground because of startup
but that's because of how rich it was running

it might not be the rings, doing a compression check is the only way to figure out if that's a problem
 
MontegoMan":1zyyjiqw said:
Burning oil, black smoke on acceleration and a large sooty mess on the ground as it starts...

How much of this is a result of worn rings?

It sounds like it is running WAY rich. Maybe a sinking float in the carb or too much choke or maybe both.
Joe
 
Thanks for the help so far...

So, the burning oil is not necessarily a sign of worn rings?
 
Burning oil is not necessarily from bad rings. It could be bad valve stem seals. Bad valve seals typically allow engine to pull in oil into combustion chamber during idle (high engine vac). When you accelerate, you will see a puff of smoke. The smoke is usually grey not usually black as you describe.

Like the others, I suspect a good deal of your smoke may be carb related and is causing the black smoke.
Doug
 
The stem seals were changed and the carb is a TOMCO rebuilt from Mac's; it is also dripping fuel onto the intake log, so I assumed the carb is pretty fouled up and I plan to rebuild it this spring or replace.

I am trying to figure out how much of my smoke/oil burning/dirty oil is caused by a rich condition, rather than a problem where a rebuild is needed such as a valve job/ring job.

I should also add another symptom:

when I firmly accelerate, the car boggs down like it has no power and sputters; when I ease up and then re-accelerate, I feel more power.

Are all these symptoms related to carb issues?
 
I found out from trial and error (mostly error) that after having my rings replaced and cyclinder walls cleaned up, that I still had a lot of oil in my exhaust system. As a result of that, the car spat out a lot of black oilly soot that somehow managed to mount itself on my rear valance and taillight pannel. Yucky, yucky.
Like it was said before, if the oil is dirty, it is doing it's job. If you want to have cleaner oil, perform more frequent oil changes. I usually change my oil and filter every three months. If you change your oil more frequently you will do two things:
1. spend a lot of money on oil
2. have clean oil and a clean motor.

Perform a compression test to see if you are loosing oil. You are loosing oil aren't you? If you are not loosing oil, don't panic. That's a good thing. I would still perform the wet/dry compression test just to see where you stand.
Now as for the rich fuel condition, I found out, again from trial and error, that a too rich condition is very bad for your motor, particularly the cylinder walls. Too much fuel will wash the cylinder walls and cause your rings to not seal properly against the cylinder walls. The only way to fix this is to have the motor honed and new rings installed. (there may be some trick that i do not know of) If you don't own your own exhaust sniffer or know of anyone who owns one, take your car to a good and credible emission repair shop. They will most likely be able to adjust your air/fuel ratio. This goes back to your rings, if the damage has been done, adjusting your carb will not fix it. it'll only prevent any additional damage.

I know this has been wordy, but I hope it helps.
Ted
 
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