Oil color variation in the engine block.

[kav]

This may be a really stupid question but going through my photos of the engine teardown and I notice this one, why is the remaining oil in the block such different colors?

The darker is coming from the sump oil return tubes and the lighter color from oil feed line from the bottom of the oil tank through the pipe on the bottom of the oil cooler (this is where it was dripping from onto the tray) and into the oil pump. This oil had about 1000 miles on it, shouldn't the oil pump have circulated the oil enough by now for it all to be the same color?

Cheers.

-Kav

[kav]

I had good oil pressure, 60psi at normal running and the temp stayed at 180.

[fanaudical]

You would think those would be close to the same color.

Stuff leaking from the oil tank has been freshly filtered on its way back to the tank.

Stuff leaking from the oil return tubes has recently been in the motor; perhaps it's picking up some dirt from the bottom of the motor on it's way down?

[kav]

I don’t think so. I’m just amazed that the oil filter can make such a difference to the clarity of the oil even after 1000 miles! Well I suppose that’s it’s job!