Just stripped down an old 1800 that lunched itself on return trip from NSW many years ago. Cruising at highway speed and a big bang and clunking. Switched of and rolled to side of road. Engine would not turn over after stopping. Short story is we got the Kombi home and changed the engine for a 2L pinched from the double cab project. Am looking at getting something up to replace tired engine in Schmetterling so pulled the 1800 out and tore it down. Bugger! Engine is trashed. Dropped valve. Destroyed piston and head. Twisted conrod. Belly full of piston bits.