Tools You'll Likely Need:
* Socket set (metric)
* Ratchet and extensions
* Screwdrivers (Phillips and possibly flathead)
* Pliers
* Wire cutters/strippers (if replacing wiring)
* Electrical tape (if replacing wiring)
* Penetrating oil (like PB Blaster)
* Shop towels
* New wiper motor
Procedure:
1. Disconnect the Battery: This is crucial to prevent accidental short circuits. Disconnect the negative (-) terminal first.
2. Access the Wiper Motor: This is usually located under the cowl (the area behind the windshield). You'll likely need to remove the wiper arms first.
* Removing Wiper Arms: Use a wiper arm puller tool (highly recommended to avoid scratching the windshield). If you don't have one, you *might* be able to carefully pry them off with a sturdy flathead screwdriver, but be extremely cautious. Once removed, set the arms aside safely.
* Accessing the Cowl: This varies depending on the specific Jeep model. You'll likely need to remove some screws and possibly plastic trim pieces around the windshield base to gain access. Refer to your repair manual for the exact location and removal procedure. You might encounter some rust or stubborn fasteners. Penetrating oil applied in advance will help.
3. Disconnect the Electrical Connectors: Carefully disconnect the electrical connectors from the wiper motor. Take pictures or make notes of how they connect to ensure correct reassembly.
4. Disconnect the Linkage: The wiper motor is connected to the wiper linkage. Carefully disconnect this linkage. Again, take pictures or notes if necessary. This may involve removing bolts or clips.
5. Remove the Wiper Motor: Once the electrical connectors and linkage are disconnected, you should be able to remove the wiper motor from its mounting location. This may involve removing several bolts.
6. Install the New Wiper Motor: Carefully install the new wiper motor, reversing the removal procedure. Make sure the linkage is properly reconnected and the electrical connectors are securely fastened.
7. Reconnect the Wiper Arms: Reattach the wiper arms using the puller tool or carefully aligning them by hand.
8. Reconnect the Battery: Reconnect the positive (+) terminal.
9. Test the Wiper Motor: Turn on your wipers and test all functions (low, high, intermittent). If they don't work, double-check all connections and ensure the motor is properly seated.
Important Considerations:
* Rust: 1990 Jeeps are prone to rust, particularly in the cowl area. Expect to encounter some rust and possibly damaged fasteners. Be patient and use penetrating oil liberally.
* Repair Manual: A repair manual specific to your 1990 Jeep Wrangler YJ is invaluable. It will provide detailed diagrams and instructions, saving you time and frustration.
* Wiring: If the wiring is damaged, you may need to repair or replace it. Use appropriately sized wire and electrical tape for a secure connection.
This is a complex task. If you're not comfortable working on your vehicle, it's best to take it to a qualified mechanic. Improper repair can lead to further damage or even injury. Remember safety first!
