Introduction
Kobalt 80V weed eaters are a top choice for homeowners and landscapers looking for a gas-free, low-maintenance trimming solution. Their powerful 80V battery system delivers consistent performance for cutting grass, weeds, and light brush, but like all string trimmer models, they require occasional restringing to keep working at their best. If you’ve ever found yourself wondering How to Restring a Kobalt 80v Weed Eater? you’re not alone. Many users assume the process is complicated, but with the right tools and a clear walkthrough, you can complete the task in 10 minutes or less, no professional help required. This guide covers everything you need to know, from understanding your weed eater’s feed system to step-by-step restringing instructions, string selection tips, and troubleshooting common issues. By the end, you’ll have the confidence to tackle this routine maintenance task yourself, saving time and money on service calls.
- What You’ll Need to Restring a Kobalt 80V Weed Eater
- How the Kobalt 80V Weed Eater Auto-Feed System Works
- Step-by-Step Guide to Restringing a Kobalt 80V Weed Eater
- Choosing the Right Replacement String for Your Kobalt 80V Model
- Tips for Extending the Life of Your Weed Eater String
- Common Mistakes to Avoid When Restringing
- Troubleshooting Common Post-Restring Issues
- Frequently Asked Questions
- How often do I need to restring my Kobalt 80V weed eater?
- Can I use a different diameter string on my Kobalt 80V weed eater?
- Why does my string keep jamming after restringing?
- Do I need to replace the entire spool when restringing?
- How much string do I need to restring my Kobalt 80V weed eater?
- Conclusion
What You’ll Need to Restring a Kobalt 80V Weed Eater
Gathering the right tools before you start will make the restringing process fast and frustration-free. First, you will need 0.080 inch diameter replacement string, which is the factory standard for all Kobalt 80V weed eater models. Using a different size can damage the auto-feed mechanism or strain the motor, so always confirm the size before purchasing string. You will also need a flathead screwdriver (for releasing the spool lock on some models), wire cutters (to trim excess string), work gloves (to protect your hands from sharp string ends), and a small soft brush (to clear debris from the spool housing). If you have your Kobalt 80V user manual handy, keep it nearby for model-specific instructions, though the steps in this guide apply to all standard 80V weed eater models. Most importantly, make sure the 80V battery is removed from the tool before you begin, to avoid accidental startup.
How the Kobalt 80V Weed Eater Auto-Feed System Works
Most Kobalt 80V weed eaters use a dual-line bump-feed auto-feed system, unlike manual feed models that require you to pull string out by hand. The system stores two separate lengths of string on a single spool, wound in opposite directions. When you bump the bottom of the trimmer head against the ground while the tool is running, a centrifugal mechanism inside the head releases a pre-set 2-3 inch length of string, so you always have a fresh cutting edge without stopping work. The spool is designed to hold enough string for 1-2 hours of continuous use, depending on the density of the weeds you’re cutting. Understanding how this system works is critical for restringing correctly: if you load the string in the wrong direction, or fail to tuck the ends into the spool notches, the auto-feed will fail to release string, or cause jams and tangles mid-use.
Step-by-Step Guide to Restringing a Kobalt 80V Weed Eater
- Prepare your weed eater for restringing: Start by removing the 80V battery from the weed eater’s battery port, and store it in a cool, dry place away from direct sunlight. Lay the trimmer on a flat, stable work surface, and place a rag or old towel under the head to avoid scratching the plastic housing. If your model has a debris shield attached to the head, remove it by unscrewing the retaining screw with your flathead screwdriver to access the spool fully. Use your small soft brush to clear any built-up grass, weeds, or dirt from the bottom of the trimmer head; built-up debris can cause the spool to stick or the string to jam after restringing.
- Remove the old spool and string: Locate the spool release mechanism on the bottom of the trimmer head. Most Kobalt 80V models use a twist-lock release: turn the spool cover counterclockwise ¼ turn until it stops, then pull the cover and spool assembly straight out of the head housing. If your model has a button release, press the button in while pulling the spool out. Once the spool is removed, pull off any remaining old string and discard it. Inspect the spool for cracks or worn notches – if the spool is damaged, you will need to replace it entirely, as a broken spool will not hold string correctly. Clean out any remaining debris from the spool housing with your brush, making sure no grass clippings are stuck in the feed holes where the string exits the head.
- Load the new string onto the spool: Cut two equal lengths of 0.080 inch replacement string, each 6-8 feet long. The Kobalt 80V spool holds enough string for 10-15 bump feeds per side, so 6-8 feet per line is sufficient for average use. Feed one end of the first string through one of the feed holes on the side of the spool, leaving 2-3 inches of string sticking out of the hole. Tuck this end into the small notch on the edge of the spool to hold it in place. Wind the string tightly around the spool in a clockwise direction, making sure the layers are neat and do not overlap – overlapping string will cause jams when feeding. Leave 2-3 inches of string at the end, tuck it into the opposite notch on the spool. Repeat this process for the second string, but wind it in a counterclockwise direction, tucking the end into the notches on the opposite side of the spool. The two strings must be wound in opposite directions to avoid tangling when the auto-feed releases them.
- Reinstall the spool and test the feed: Align the spool with the feed holes in the trimmer head housing, making sure the ends of both strings are sticking out through the holes. Push the spool into the housing until it clicks into place, then twist the spool cover clockwise ¼ turn to lock it. If your model uses a button release, make sure the spool is fully seated before releasing the button. Reattach the debris shield if you removed it earlier. Insert the 80V battery into the weed eater, and turn it on. Hold the trimmer head a few inches above a patch of grass, and bump the bottom of the head against the ground 2-3 times. You should see 2-3 inches of string release with each bump. If the string does not feed, turn off the weed eater, remove the battery, and check that the string is loaded in the correct directions, and that the ends are tucked into the notches. Trim any excess string with your wire cutters so it is even with the trimmer head’s cutting radius.
Choosing the Right Replacement String for Your Kobalt 80V Model
Not all weed eater string is created equal, and using the wrong type for your Kobalt 80V can lead to poor performance, frequent jams, and even damage to the trimmer’s motor. The factory-recommended string diameter for all Kobalt 80V weed eaters is 0.080 inches, which balances cutting power and motor strain. Using a thinner string will wear out faster and may not cut through thick weeds effectively, while a thicker string will overload the 80V motor, reducing battery life and increasing the risk of overheating. When selecting string, you can choose between generic 0.080 inch nylon string or genuine Kobalt-branded replacement string, which is formulated to match the feed system’s specifications exactly. For most residential users, standard round nylon string is sufficient, but if you regularly cut thick brush or weeds, a square or spiral cut string will deliver better cutting power. The comparison table below outlines the most common string types and their ideal use cases to help you choose the best option for your needs.
| String Type | Best Use Case | Durability Rating (1-5) | Average Cost per 50ft Roll |
|---|---|---|---|
| Round Nylon (Standard) | General residential use, light weeds, grass | 3 | $5 – $8 |
| Square Nylon | Thick weeds, brush, edging | 4 | $8 – $12 |
| Polymer Coated | Wet, muddy conditions, heavy use | 5 | $12 – $18 |
| Spiral Cut | Maximum cutting power, dense overgrowth | 4.5 | $10 – $15 |
Tips for Extending the Life of Your Weed Eater String
Proper maintenance and usage habits can drastically extend the life of your replacement string, reducing how often you need to restring your Kobalt 80V weed eater. First, avoid bumping the trimmer head against hard surfaces like concrete, rock, or pavement unnecessarily – each bump wears down the string slightly, and hard impacts can damage the auto-feed mechanism. Second, adjust the trimmer’s cutting height to match the density of the weeds you’re cutting: cutting very thick, woody brush will wear out string far faster than trimming grass. Third, store your weed eater and replacement string in a cool, dry place away from direct sunlight, as UV exposure and extreme temperatures can make nylon string brittle and prone to breaking. Finally, restring your trimmer as soon as the string is worn down to 2-3 inches or less – waiting until the string is completely gone can cause the spool to jam, and may damage the feed mechanism.
Common Mistakes to Avoid When Restringing
Even experienced DIYers make errors when restringing a Kobalt 80V weed eater, leading to poor performance or damage to the tool. The most common mistake is using the wrong string diameter: always confirm you are using 0.080 inch string, as even a small difference in size can cause the string to slip or jam in the feed holes. Another frequent error is winding both strings in the same direction on the spool – this causes the lines to tangle as soon as the auto-feed releases them, leading to frequent jams and uneven cutting. Failing to tuck the ends of the string into the spool notches is another common issue: if the ends are not secured, they will slip out of the feed holes while you’re working, leaving you with no cutting line mid-job. Over-tightening the spool when reinstalling it can strip the plastic threads on the trimmer head, making it impossible to lock the spool in place. Finally, skipping the step of removing the battery before restringing is a serious safety hazard: if the trigger is accidentally pressed while you’re working on the head, the trimmer can start unexpectedly, causing injury.
Troubleshooting Common Post-Restring Issues
If you’ve restringed your Kobalt 80V weed eater and are experiencing issues, most problems can be fixed with a quick adjustment. If the string is not feeding when you bump the head, first turn off the trimmer and remove the battery. Remove the spool and check that the string is wound in opposite directions, and that the ends are tucked into the notches and sticking out of the feed holes. If the string is tangled inside the housing, remove the spool and untangle it, then rewind the string neatly. If the string breaks frequently while cutting, check that you are using the correct 0.080 inch diameter string, and that you are not bumping the head too hard against the ground. Cheap, low-quality string is also prone to fraying and breaking, so upgrading to a higher-quality nylon or polymer coated string can solve this issue. If the motor strains or makes unusual noises after restringing, check that the spool is installed correctly and not jammed against the housing, and that you did not use string that is too thick, which can overload the 80V motor.
Frequently Asked Questions
How often do I need to restring my Kobalt 80V weed eater?
The frequency of restringing depends on how often you use the trimmer and the type of weeds you cut. For average residential use (trimming grass and light weeds 1-2 times per week), you will need to restring your Kobalt 80V every 2-4 weeks. If you regularly cut thick brush, woody weeds, or use the trimmer for commercial landscaping, you may need to restring it every 1-2 weeks. You’ll know it’s time to restring when the string is worn down to less than 2-3 inches, or when the trimmer no longer cuts effectively even after bumping the head to release more string.
Can I use a different diameter string on my Kobalt 80V weed eater?
No, you should only use 0.080 inch diameter string on your Kobalt 80V weed eater, as this is the size the auto-feed system and motor are calibrated to handle. Using a thinner string (such as 0.065 inch) will wear out faster and may not provide enough cutting power for thick weeds, while using a thicker string (such as 0.095 inch) will put excess strain on the 80V motor, reduce battery life, and can cause the feed mechanism to jam. If you are unsure what size string to use, check the label on the inside of the trimmer head housing, or refer to your user manual for model-specific recommendations.
Why does my string keep jamming after restringing?
String jams after restringing are almost always caused by one of three issues: incorrect string loading, using the wrong string size, or built-up debris in the spool housing. First, confirm that you wound the two strings in opposite directions, and that the ends are tucked into the spool notches and sticking out of the feed holes. If the strings are wound in the same direction, they will tangle as soon as the auto-feed releases them, causing a jam. Second, confirm you are using 0.080 inch string, as thicker or thinner string can get stuck in the feed holes. Finally, remove the spool and clean out any grass, weeds, or dirt from the housing, as built-up debris can block the string from feeding properly.
Do I need to replace the entire spool when restringing?
No, you do not need to replace the entire spool when restringing your Kobalt 80V weed eater, unless the spool is cracked, broken, or has worn notches that no longer hold the string in place. The spool is designed to be reused indefinitely, as long as it is not damaged. When removing the old spool, inspect it carefully for cracks or worn edges – if the notches that hold the string ends are stripped, the string will slip out during use, and you will need to purchase a replacement spool, which is available from Kobalt or most hardware stores that carry Kobalt 80V parts.
How much string do I need to restring my Kobalt 80V weed eater?
You will need approximately 12-16 feet of 0.080 inch replacement string to fully restring a standard Kobalt 80V weed eater, as the spool holds two lines of 6-8 feet each. If you have a larger capacity spool or use an extended reach attachment, you may need up to 20 feet of string. It is always a good idea to buy a full 50ft roll of replacement string, as they are inexpensive and you will have extra on hand for future restringing needs. Avoid buying small, pre-cut packs of string, as they are often overpriced per foot compared to full rolls.
Conclusion
Restringing a Kobalt 80V weed eater is a simple, routine maintenance task that anyone can complete with basic tools and a clear guide. By using the correct 0.080 inch replacement string, following the step-by-step process outlined in this guide, and avoiding common mistakes like winding the string in the wrong direction or using the wrong diameter, you can keep your trimmer running smoothly for years. Regular restringing, combined with proper storage and usage habits, will extend the life of both your string and your weed eater’s motor, saving you money on replacements and service costs. If you ever run into issues, refer back to the troubleshooting section or consult your user manual for model-specific guidance. With these tips, you’ll never have to wonder How to Restring a Kobalt 80v Weed Eater? again, and you’ll be able to tackle your yard work with a consistently sharp, reliable trimmer.