One question - did you tighten fitting-to-hose as opposed to fitting-to-fitting (where the hose joins the cooler/thermostat)? These hoses aren't crimped on, but instead use a screw-together technique. The hose slips over the small pipe at the backside of the fitting and that tapered collar then screws onto the fitting itself and clamps the hose tight. Check on that first, and if it's as tight as it will go (they're aluminum and soft, so be careful), then you will likely want to get new hoses. Those in the link you supplied are the right ones, but you need to be sure to get the right length and the correct style fittings (straight or angled).