1. Helical Insert (Helicoil or similar): This is generally the best solution for a permanently fixed repair. Helical inserts are small, threaded metal coils that are installed into the stripped hole. They create new, stronger threads.
* How it works: You drill out the stripped hole to the correct size for the insert, then install the insert using a special installation tool. These tools are relatively inexpensive and can be rented or bought at auto parts stores. Once installed, you can then screw the wiper arm bolt into the insert.
* Pros: Strong, permanent repair.
* Cons: Requires special tools and some mechanical skill. If you've never done this before, it might be best to take it to a mechanic.
2. Larger Bolt and Epoxy: This is a less ideal but potentially workable temporary solution.
* How it works: Carefully drill out the existing stripped hole slightly larger. Then, select a slightly larger bolt with a corresponding sized washer. Mix a strong two-part epoxy (like JB Weld) and fill the enlarged hole with it. Insert the larger bolt into the epoxy-filled hole and let it cure completely according to the epoxy manufacturer's instructions.
* Pros: Relatively easy and inexpensive.
* Cons: Not as strong as a helical insert and can be prone to failure over time, especially in the harsh weather conditions wiper arms endure. This is not a recommended long-term solution.
3. Weld Nut: If you have welding experience, this is a very strong option.
* How it works: You'll weld a nut onto the back side of the wiper arm mounting point. This requires access to the backside of the mounting point which may be difficult depending on the vehicle design.
* Pros: Extremely strong and permanent repair.
* Cons: Requires welding skills and equipment.
4. Replacement Wiper Arm Mounting: This is the most expensive but also potentially the easiest and most reliable if you're not comfortable with the other options.
* How it works: The entire wiper arm mounting assembly might be replaceable. You may need to remove the cowl to fully access the area. Check a parts store or online retailer to see if this is an option and how much it costs.
* Pros: Easy if you're mechanically inclined and have the replacement part.
* Cons: More expensive than other options.
Before you start:
* Identify the problem: Make absolutely sure the problem is a stripped hole and not just a corroded or damaged bolt. Try penetrating oil and a new bolt before resorting to more drastic measures.
* Gather the necessary tools: If using a helical insert, you'll need a drill, drill bits, and the insert installation tool. If using epoxy, have the appropriate mixing tools and some way to securely hold the bolt in place while the epoxy cures.
* Consider professional help: If you're not comfortable with any of these repairs, take it to a mechanic. The cost of a professional repair will likely be less than the cost of a botched DIY repair.
Remember safety first. Always disconnect the battery before working on any electrical components of your vehicle. If unsure about any of the steps, seek professional assistance.
