Those were originally steel and even for a plastic one the newness of that looks aftermarket. My plastic one has not melted anyway. Is the bolt correct? It should be a shoulder bolt
Possibly aftermarket don't know, the bolt is not shouldered but a good point, it did spin freely, I guess a lump of ally and an hour on a lathe would solve the melting problem but must have been worm. All runs fine.
Because the hole goes through into the case the correct shoulder bolt that can be tightened right up is the thing to have.
There are some plastics that will not melt in the heat from the engine, then there are the generic cheap white plastic pulleys from hardware stores... BODGE !
