just flushed once, refilled.
Is there any way to determine if this is motor oil or not? If it's not oil, I'll get a timing chain kit and put it back together and flush it.

 

I can't tell you without seeing it in person, But if you were to take some clean coolant in a clear cup, and add a blotch of the same oil that's in your engine (loosen your oil filter) you could compare it to some of that stuff in a cup and see if it's the same. If it is, its probably oil. But since you haven't found anything wrong with your engine, I would say it may be from the last truck and you should have flushed it better.

 

hmmm...tried this...looks like oil. oh well

 

[QUOTE=Sandman;52244047]90 4runner with 22re, engine running fine, not overheating, no white smoke, oil looks decent. Did compression test, all cylinders around 155/160psi. pulled rocker cover, looks clean inside, chain guides still there. The oil in the rad is pretty thick and syrupy... seems like a lot of oil made it into the coolant. Any advice on how to procee.

I also have a 22re 5 speed manual pickup that I rebuilt not long ago. A milky gray foam is accumulating in the radiator and the oil level is dropping becouse of it. The only thing I could think of it being is the head, I had it resurfaced but also noticed that there was two hair line cracks in two of the exhaust ports. The head was not in good condition and was worped almost to the point of no repair, my best guess is that the head is shot

 

I may be completely wrong, but doesn't this statement explain it? You used the rad from a truck that already had a HG blown, so there would be oil in the coolant/coolant in the oil, so the rad most likely still had oil in it? One flush may just not have been enough.

Just a thought.