[mongocanfly]

Does your water temp climb rapidly to the 190 mark if it does then you probably have a air pocket in the engine and its not circulating...I've done a couple of the swaps and the only way I can get them to circulate is to fill the engine thru the top radiator hose. I would say not to plug the overflow/bypass,,you may create a radiator bomb,, its there for a reason..add the tank if you have to.