Yeah right , in the same episode they also said that dropping a penny down the carb while the motor was running it wouldn't do any damage ..... Somewhere (stuffed if I can find it) I've got a piston that had a spring washer bouncing around on top of it , it's rooted and the rings look like a long section of a mountain range ...... The longest unbroken bit is about 6 mm .

As for the leak , try to fix it from the outside with an epoxy putty first , make sure you get the surface really clean and mybe scuff it a bit to get a better grip , then put a commercial radiator sealer in it as well . The epoxy should hold it from the outside and if it does seep out at all the radiator sealer will plug it from the inside . Better to have something working from each side than only one . But try again to get it welded properly first and if they won't then try epoxy etc .

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