Hi my 1.9 s#@t itself when the bottom crank pulley bolt sheared off, slamming the valves into the pistons. Bent all 4 exhaust valves. But when I took the head off found there where cracks running between each pair of valves but then found cracks running from inlet valve to injector. Is it fukced. I'm a welder by trade and a friend said they can be welded. Is this true?