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Join Date: Feb 2008
Location: United Kingdom
You've cooked it, that means a full rebuild, having read your blog though, I would have advised changing the expansion cap before the level was allowed to go low enogh to let the problem get this far. The noise is probably the water pump breaking up, very rare but if it's been run dry I wouldn't be surprised.
Your low power problem cold be anything and you need some diagnostics running before you totally kill this engine.