Crankshaft woodruff key

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These aren't typically wear items, but after 30 years they're not exactly new, and they can get damaged by multiple timing belt changes. Hedge your bets and get a new one. 

For big nose engines only. That's all 1.8 engines and all 1.6es after mid-91. On a 1.6 engine, count the number of slots on the face of the crank pulley - eight is a big nose, four is a small nose.