I have a 39 Elto Fleetwin and I noticed that one of the freeze plugs were replaced by a nickel. There is a slight crack to the head where the nickel was forced in. If I get ithe crack welded do I need to take the nickel out and put a freeze plug in?
You could try pressurizing the cooling system with soapy water and compressed air. If the crack does leak I wouldn’t worry about it. Lots of old motors running around with pennies and nickels in the water jackets.