I have a Universal Model 25 with the 3" heat exchanger 299835. One of the mounting hose clamps failed and the heat exchanger vibrated against the underside of the exhaust elbow and developed a puncture leak. The leak is of sea water, not the internal coolant. Can this be fixed with a weld? The cylindrical shell of the exchanger appears to be a copper alloy - is the repair a solder? Thanks for any advice - I'm trying to avoid buying a new one for $350....By the way - the clearance between the 3" exchanger and the exhaust elbow is about zero - is there any trick to mounting this? Thanks