20 PSI may split a seam.
Why not take it to a radiator shop. They have the proper equipment to do it in a couple of minutes. And if it is no good they can do the repair as well.
Sometimes saving a dime will cost you a dollar...
Taking it in tomorrow for flush and check.
I was wanting to check for leaks myself to see if they might try and scam me... When talking on the phone with the shop, the guy pretty much told me it's gonna be trash due to the age and to plan on just saving the top and bottom with a recore.
