crankshaft keys?
 

can someone please explain the crankshaft keys for me? is mine a two-way or three-way? I got a 1992 Nissan 240sx SE KA24DE

when you remove your crankshaft you will see keyways on the nose of it... where the crankshaft pully oil pump drive and crankshaft timing gear are... they are half moon shaped and hold the part i listed above in place...you wont know until you get the crank all the way out...

can the keys be replaced?

you can buy new ones yeah... just get em from nissan... the ones from autozone are not big enough...