Best way to clean engine oil out of transmission

[Mopower71]

Best way to clean out oil?

727 out of a new to me 66’ Belvedere. What I thought was seriously burnt ATF turned out to be motor oil. Tearing it apart anyway since I found a piece of a snap ring in the pan. What’s the best way to clean the oil out that won’t damage any seals that I might miss and material on the bands?

This is out of my sons 1966 Belvedere 2, he bought this a few months ago and still hasn’t driven the car. After pulling the dipstick and finding engine oil on the dipstick,he drained it and it’s almost like someone filled it with used motor oil.
Thanks for any help with cleaning suggestions.
We already have a rebuild kits but only the front band.is it possible to clean the other band with something?
Also something I have never seen the front clutch pack has 2 steels in the bottom and then alternates. Is this ok to run this way? Right now it has .070” measured under the retaining ring.

 

[pnora]

Looks like aged worn possibly burnt atf to me. Clean everything well and blow it out. If the converter has a drain plug you can drain it well. Possibly get it flushed. There are ways you can flush it yourself.

 

[Mopower71]

It doesn’t have the burnt transmission oil smell.not a hint of red.smells and feels like used motor oil.
The converter does have a drain plug and will be getting drained and flushed as well as I can. Flipped the converter over to drain and and very little came out.
The clutches and bands look quite new,and no heat marks on the steels.

 

[oldkimmer]

It probably has trans hydraulic fluid. Kim

 

[RemCharger]

I poured engine oil in the heat of the moment when I was a kid once.. luckily drained it out before using..
My concern would be clutch and band contamination. All you can do is flush it and try it

 

[Photon440]

Rinse everything with acetone. Any traces of acetone that remain in the passages will be mixed with the ATF and quickly evaporated when the transmission is at operating temperature.