ISX450 coolant issues

[Waterloo]

Did your mechanic cut the block and use shims when setting the new liners? Is it on the repair bill? Might want to take a look... Been there, and done that. Should be listed on your bill, if it is not... Get a block test kit from NAPA, around $50, warm the engine up, get her hot and then run the test. Make sure the stopper is stuffed in the coolant jug firmly. It may take up to 10 or 15 minutes to properly run the test. Get that coolant HOT, 180* plus.