Tools You'll Need:
* New distributor cap and rotor: It's best to replace both at the same time, as the rotor often wears similarly to the cap.
* Socket wrench and sockets: You'll need the correct size to remove the hold-down bolt (if applicable). Often, a simple wrench will suffice.
* Screwdriver (possibly): Some distributor caps have screws holding them in place.
* Gloves: To keep your hands clean.
* Wrench (possibly): To loosen the distributor hold down clamp if present.
* Shop rag or paper towels: For cleaning.
Procedure:
1. Safety First: Disconnect the negative (-) battery cable before you begin. This prevents accidental electrical shorts.
2. Locate the Distributor: The distributor is usually located on the engine, near the firewall, and connected to the ignition coil. It's a cylindrical component with wires coming from it.
3. Remove the Wires: Carefully remove the spark plug wires from the distributor cap. Pay close attention to the order they're connected. Take a picture or make a diagram before removing them to ensure correct reinstallation. Numbering the wires is also a good practice.
4. Remove the Hold-Down Clamp (if present): Some G20s have a hold-down clamp securing the distributor. Loosen this clamp with the appropriate wrench.
5. Remove the Distributor Cap: Once the wires are disconnected, gently lift off the distributor cap. Sometimes there's a small clip or screw securing the cap. If so, carefully remove these.
6. Remove the Rotor (if replacing): The rotor is usually held in place by friction. Gently pull it straight up and off the distributor shaft.
7. Install the New Rotor (if replacing): Carefully slide the new rotor onto the distributor shaft. Make sure it's aligned correctly.
8. Install the New Distributor Cap: Carefully align the new distributor cap over the distributor, ensuring it sits correctly over the rotor and contacts all the terminals. Push it down firmly to seat it.
9. Reconnect the Spark Plug Wires: Carefully reconnect the spark plug wires to the distributor cap in the *exact* same order you removed them. Refer to your diagram or picture. Double-check everything!
10. Reattach the Hold-Down Clamp (if applicable): Tighten the distributor clamp if you removed one.
11. Reconnect the Battery Cable: Reconnect the negative (-) battery cable.
Important Considerations:
* Firing Order: The firing order for your engine is crucial. Consult your owner's manual or a reliable online source to verify the correct order. Incorrect wiring will lead to engine misfires or failure to start.
* Rotor Position: Ensure the rotor is properly aligned with the number 1 cylinder before installing the cap. This is essential for proper ignition timing.
* Distributor Shaft Wear: While replacing the cap and rotor, inspect the distributor shaft for excessive wear or damage. If it's worn, the new parts may not function correctly. A worn shaft may require professional attention.
If you're uncomfortable performing this repair yourself, it's best to take your van to a qualified mechanic. Incorrect installation can cause serious engine damage. Remember to always double-check your work before starting the engine.
