Follow the steps below to replace the wire plunger in the Nanoject II:

1. Remove the collet and all collet components.
2. Hold the motor housing and unscrew the aluminum barrel. Once free, pull it off.
3. You will see a brass fitting with two Allen screws. Unscrew these using the provided wrench.
4. Remove the old plunger and replace with a new one.
5. Replace the screws and tighten making sure the wire is seated fully and is straight.
6. Replace the aluminum barrel and collet.