NC Engine Serpentine Belt Pulleys
Posted: Thu Sep 13, 2012 3:59 pm
The NC engine can make a rather alarming metallic clacking/rattling noise from the front when coming off idle or with the A/C cycling on and off. The problem is most likely the automatic tensioner pulley and/or the idler pulley for the serpentine belt. My car has done 66,000 km
Replacement is pretty straight forward once you remove the battery and the battery box. There is a good DIY here: http://forum.miata.net/vb/showthread.php?t=472887
Notes:
1. There are only four (4) screws holding the battery box in.
2. Disconnecting the wiring harness from the battery box without breaking the retainers is a bit of a pain. The top section of the battery box "clips" onto the base. I recommend removing the top section of the battery box to get easier access to the wiring harness and one of the retaining screws.
3. The tensioner pulley LF17-15-980E set me back $220 and the idler pulley LFH1-15-940A was $112.
4. I can't believe how quiet the engine is now.
Replacement is pretty straight forward once you remove the battery and the battery box. There is a good DIY here: http://forum.miata.net/vb/showthread.php?t=472887
Notes:
1. There are only four (4) screws holding the battery box in.
2. Disconnecting the wiring harness from the battery box without breaking the retainers is a bit of a pain. The top section of the battery box "clips" onto the base. I recommend removing the top section of the battery box to get easier access to the wiring harness and one of the retaining screws.
3. The tensioner pulley LF17-15-980E set me back $220 and the idler pulley LFH1-15-940A was $112.
4. I can't believe how quiet the engine is now.
