Am not happy

on the way to sunny Bournemouth i heard a massive BANG...... i looked over at my passenger and thought what the hell was that after what sounded like a blowing exhaust i later found this...........

the bolt has loosened off the thread and eventually burst off down the M27 somewhere

gonna see if i can replace the bung if not then just weld it closed, it sounds horrible then after all this i found engine coolant leaking onto the ground beneath the engine

im still not sure what or where its coming from... at first look it seems to be below the manifold area, im hoping its nothing serious as im really straped for cash at the moment, a friend has told me the leak could be a result of a burst pipe im sure this is where the leak is as you can see some signs of water there am i right to believe this...

can anyone help please??
Cheers Arran.