Broken Marine Engine Heat Exchanger - How we 'Unbroke' it!

I'd been asked to repair a badly corroded heat exchanger from a small marine engine. This involved machining some new parts, then a trip to Maximus Ironthumper's workshop for a bit of blasting, spraying and burger eating before heading down to the boatyard in Plymouth for fitting and testing. No vessels were sunk in the making of this video!