Oil too black?

scr11 · #1 (**permalink**) 03-27-2002, 07:37 PM

I've about 1700 miles on my 393 stroker. I've changed the oil 3 times now (last at 1000 miles). While checking the level tonight, the oil seemed pretty black to me. I'm using Pennzoil 10-40 until I get about 5000 miles or so, then I'll switch over to Mobil 1. The question is, how black should the oil be? I thought it would be light brown. I thought only old engines turned oil black. Should I be concerned about this or no?
Thanks
Scott, SPF #1230 / 393

Richard Hudgins · #2 (**permalink**) 03-27-2002, 07:47 PM

Scott,

You might wish to check your plugs. If you are quite rich, you will blacken the oil very rapidly. This is due to unburnt fuel getting by the rings, etc.

Oil should not blacken for many miles, unless you have impurities getting into it.

I would look at this fairly quickly, as washing down the cylinder walls is not good for longevity of the motor.

DAVID GAGNARD · #3 (**permalink**) 03-27-2002, 07:50 PM

Scott;

I use Rotella T which is a diesel grade oil and my oil turns black in about 200 or so miles....I asked about it and was told it had to do with the additives in the oil itself,not that the engine is dirty.... Actually took the valve cover off my company car at 125,000 miles to replace it and the top of the head could have passed for 125 miles,it was that clean,so I know it is not the engine....I guess some oils will change colors before others, just depends on the oil,unless you have a lot of blowby,then that would affect your oil.....
Just my .02 cents......

David

scr11 · #4 (**permalink**) 03-27-2002, 07:58 PM

I've been checking the plugs recently and they all have a light brown color. None of the plugs looked too white or too black. However, I've been adjustung the timing a bit and I'm about to adjust the fuel/air mixture as I might be just a hair rich right now.

Richard - if I was running rich enough to get fuel down the piston walls, wouldn't my plugs be dark or black themselves?

Thanks!

Richard Hudgins · #5 (**permalink**) 03-27-2002, 08:37 PM

Quote:

Originally posted by scr11
I've been checking the plugs recently and they all have a light brown color. None of the plugs looked too white or too black. However, I've been adjustung the timing a bit and I'm about to adjust the fuel/air mixture as I might be just a hair rich right now.

Richard - if I was running rich enough to get fuel down the piston walls, wouldn't my plugs be dark or black themselves?

Thanks!

Scott,

You would think that your plugs would be showing a very dark color. However, if you are running a modern plug, IE platinum, etc. these plugs will not color as the normal plugs do.

There is also the issue of idle mixture and mixture at 3000.

If your idle is rich, you will not color the plugs very much. At 3000 or above you will clean the plugs and give yourself a bad read.

Very confusing, I know!!!!!!

The best thing to do is go to a shop that has a tailpipe mixture probe and read the mixture at various rpm's. (CO content)

Or go to a chassis dyno place. These folks usually know what they are doing and can dial you in correctly.

Oil should not get dirty in 700 miles.

scr11 · #6 (**permalink**) 03-27-2002, 09:05 PM

Thanks for the replies. I'll be putting the car on a chassis dyno at Houston Performance. We'll be doing a wide band and some jetting work at well. This should take care of any and all rich/lean issues. It'll take a few weaks to get an appointment so I'll take it easy until then.
Scott

scr11 · #7 (**permalink**) 03-29-2002, 04:04 PM

My dyno date isn't until the 11th, but here's what I found out in the meantime:
I was actually running a little on the lean side. So I shouldn't have any issues with gas bleeding down the cylinder wall.

As for the color of the oil, I had the shop owner look at it and he said it looked fine, maybe a little dirty, but nothing to worry about.
So, I was worried about nothing - some times I do that.

Thanks for the ideas.
Scott, SPF #1230 / 393