what could have caused this?

[JohnnyP]

Originally Posted by adichino

thanks for the checklist dude, i do however like to fix my own stuff even though its my first time when dealing with an engine - worst case scenario i cannot fix it and buy a new one and lose a couple of euros, fuck that

i replaced the crankshaft because it was damaged where the rod which snapped is attached - dunno how its called

i didnt replace the bearings as they all looked the same and good to me

i am using a new set of pistons with a new set of rods - i didnt check the cylinders, just cleaned them and installed the pistons - they were sliding smooth when the rods were not attached to the shaft

so you are saying - judging by your answer - after the rods are installed and tightened the pistons should move when rotating the crankshaft?

quote from wikipedia

If you didnt change your case and rod bearings to match your new crank you engine will not last long....The chances that you got the exact same journal sizes on your new crank are a million to one....