I think the air would just head into the housing instead I through the lines, path of least resistance. Plus I don't think you can truly use air to get all the oil out if it wasn't the case. I would rather put a drain plug on the bottom of cooler. That should remove most of the oil, but will still have some pooling in the lines.
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1983 123.133 California
- GreaseCar Veg System
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