The color of the oil in our engine

[Bavafa]

I was wondering if the color of the oil in our engine can be used to indicate any thing in our engines?
I have been changing my oil in our cars for the past 30+ years so I am quite used to seeing old oil that comes out of our cars and know that dark oil does not necessarily mean a near kaput engine just as I know that even a 500-1000 mile on an oil would make it go dark to some degree.

On the other hand, In my plane, I often see a rather fresh-looking oil color even after 30 or more hours of flying. So I was wondering would a lack of dark color in oil mean anything bad?

 

[Sig600]

I don't remember where I read it, but yes engine color can be used to determine oil abuse.

I still wouldn't change the interval though. Oil change is a good opportunity to do a firewall forward conditional. Things like fuel and oil leaks need to be caught early.

I also do an oil analysis every oil change.

http://www.blackstone-labs.com/free-test-kits.php

$25, they send you the kit for free. Just fill out the slip, mail back the bottle. They'll not only email you the results but they'll keep track of them and give you trend analysis on what could be what. It's the only true way to find out what is going on in there.

 

[mike newall]

I used to notice that Lycoming went dark gray and Continental went green - don't ask me why.......

 

[BillL]

There are many parameters of oil degradation, one of these is oxidation and is measured in the lab. Time at temperature will darken the oil due to oxidation. Lack of darkening means that it runs cooler in your engine. That is good.

Do you run 100LL or mogas? I would expect mogas to leave the oil more honey colored not the typical progression of opaque color.

Oils see different temperatures in different engine. My Saturn turned the oil black in 3000 miles (hot), I switched to synthetic Mobil1 and it still darkened significantly in 3000. My neighbors Honda Civic oil at 3000 miles still looked new. His Civic engine lasted significantly longer.