Black and Decker Weed Eater How-to and Troubleshooting Guide

Black and Decker Weed Eater How-to and Troubleshooting Guide

If you live in a region that experiences wet spring weather, it is more likely that your yard looks like a mini rolling hay field. And with summer around the corner, you need to whack the grass to make your yard inhabitable.

And what better way to do it than by using your weed eater? However, it may need maintenance if you haven’t used your weed eater in a while. And troubleshooting if it was already failing when you stored it away.

Keep reading to learn how to use your weed eater efficiently. And to repair any issues it may have.

My gasoline Black and Decker weed eater won’t start

Here are some reasons why your gas-powered weed eater will not start;

Fuel Issues

Fuel Issues are the most common problems you will need to solve over the life of your weed eater. Here are a few of the more common fuel issues that may be causing a problem:

  • The fuel is running low
  • The tank is full but with old fuel. Oxygen and moisture can damage the fuel over time.
  • The gasoline and oil have separated, preventing the engine from getting enough fuel.

Troubleshooting Fuel Issues

To solve fuel-related problems, proceed with these steps:

First, check the level of fuel in the tank. If it is empty or low, the weed eater will not start. If there is enough fuel and it is fresh, lightly shake and swirl the weed eater to ensure that oil and gasoline are not separated.

If you are using the weed eater for the first time after several months, you should swap the old fuel for a new mixture. Many string trimmers require a 40:1 or 50:1 gas-to-oil ratio. (Check your owner’s manual for your model’s requirement).

You must use gasoline with only 10% alcohol or an ethanol-free variety and oil designed for 2-cycle engines. This allows for the piston and crankshaft to stay lubricated.

Spark Plug Issues

If you have tried to turn the engine on and it is not giving you any sign of life, the problem might lie in the spark plug.

A fouled spark plug won’t be able to deliver electric current from the ignition system, which is necessary to ignite the fuel in the combustion chamber of your weed eater. In this case, the possible issues are:

  • A dirty spark plug
  • A cracked or faulty spark plug

Troubleshooting Spark Plug Issues

If the problem involves a dirty spark plug, you can quickly solve it by cleaning it with a spray-on plug cleaner (source). To remove any extra debris, scrap the spark plug with a knife. For the best maintenance, you should clean the spark plug every season and after prolonged use (around 25 hours).

If the spark plug is cracked or faulty, you will need to replace it altogether. These are inexpensive and easy to buy in your local DIY store. To check for a damaged spark plug, you should:

  • Disconnect the lead and clean the surrounding area
  • Remove it using a spark plug socket
  • Check the porcelain for cracks and scratches

Assuming it isn’t cracked, it probably just needs a good cleaning. Once cleaned, replace the spark plug, ensuring that it is not too tight, and try to restart the engine.

Carburetor Issues

The carburetor is the heart of the engine. It controls the engine’s speed and the ratio between fuel and air. If your carburetor is amiss, dirty, or cracked, your weed eater won’t work. Some common telltale signs of a fault carburetor are:

  • Black smoke
  • Backfiring
  • Overheating

It is hard to start or bogs down and dies when the engine is throttled

Troubleshooting Carburetor Issues

The first thing we want to do is to clean the carburetor. It’s a fairly easy task and doesn’t require a lot of tools.

Depending on your weed eater model, start by removing the filter cover and the filter. Then proceed by unscrewing the screws that hold the primer bubble in place. Once you have opened your carburetor, you can clean it thoroughly and unclog the filter.

You may be able to clean the carburetor without needing fresh gaskets, but as a rule, it’s best to have an inexpensive rebuild kit like this one (link to Amazon) handy. If this one doesn’t match your weed eater’s engine, just search for your brand.

How to Clean a Two-Cycle/Two-Stroke Engine Carburetor

  • Put on protective gear, switch off the engine, and remove the air filter’s housing along with any hoses and linkages and the bottom bowl
  • Vacuum away any loose dirt, dust, debris, grime, and great on the surface with a handheld and cordless vacuum
  • Lay out rags or cloths at the base of the carburetor to catch runoffs and protect the surfaces
  • Apply the carburetor and choke cleaner in thin, even coats. Then, wait for it to settle and work its magic
  • Wipe the filth away along with the cleaning solution applied using a microfiber towel and extra help from a stiff-bristle brush or a wire brush
  • Wipe the carburetor down with a fresh, dry towel and double-check that it is dried completely
  • Remove the rags or cloths at the base of the carburetor and other tools to run a performance test on the engine
  • Return the air filter housing, bottom bowl, hoses, and linkages to their original setup.

Air Filter Issues

The air filter is another essential part of a 2-stroke engine. It allows fresh air (oxygen) to enter the combustion chamber. This is necessary for the ignition process to begin.

At the same time, air filters ensure that no external and potentially damaging debris enters the engine while delivering a clean oxygen flow.

The air filter can become blocked or dirty after prolonged use or if you have stored your weed eater for too long. A common sign that the main issue with your string trimmer lies in the air filter is the engine starting and then stopping abruptly after a couple of minutes.

Troubleshooting Air Filter Issues

Air filter problems can be solved quickly by cleaning or replacing the filter.

  • Start by removing the screws that hold the air filter in place, usually near the rear of the engine.
  • Clean the air filter with warm water and dish soap
  • Once cleaned, you can soak the filter in lukewarm water
  • Rinse and squeeze it various times to remove all the remaining water and soap in the pores.
  • Let the filter air-dry and place it back only once it is fully dry.
  • It’s often better to just replace these. They are very inexpensive.

Flooded Engine Issues

If you tried to fix any of these issues without knowing how to do it, the chances are that you kept trying to restart the engine. As a result, you now have a weed eater that won’t start and a flooded engine.

Like an older car, the engine of your weed eater can be “flooded” with a too-rich blend of fuel and air.

Troubleshooting Engine Issues

The weed eater’s simple engine makes it easy to unflood a weed eater. Usually, all you will need to do is:

  • Ensure that the on/off switch is on the “on” position
  • Position the choke “off.”
  • While holding the throttle trigger, pull the starter recoil several times quickly. This may take a lot of pulls.
  • Keep holding the trigger while black smoke leaves the weed eater.
  • Release the trigger

This process of repeatedly pulling on the starter recoil while holding the throttle down allows the weed eater to get rid of any extra fuel that has filled the combustion chamber. It’s common to see black smoke resulting from the engine. That’s the weed eater burning off the excess fuel.

Tips For Keeping Your Weed Eater Running

Once you have it running again, there are a few best practices that you should implement to make sure your weed eater is running at top performance:

Use fresh, ethanol-free fuel. I highly recommend buying a premix. It costs more upfront, but you never have to worry about improper gas-to-oil ratio mixtures or accidentally using two-stroke oil that has gone bad.

Replace the spark plug and air filter at the beginning of every season. It’s super-inexpensive and will keep your engine running trouble-free.

The majority of issues you’ll encounter with a 2-stroke yard tool’s engine can be avoided with just a little preventative maintenance and good choices, especially regarding the fuel quality you use.

Why won’t my electric Black and Decker weed eater to start

Before you investigate bigger problems causing your Weed Eater to lose power, ensure the switch is turned to the “on” position. Ensure the power cord is plugged in.

Here are reasons why your electric weed eater is not working;

Faulty power source

Inspect your electric trimmer to ensure its extension cord is plugged firmly into the machine and an electrical outlet. A faulty extension cord also may be the problem.

A quick fix can be performed by swapping the faulty extension cord for another extension cord in working order. Also, ensure the trimmer’s switch is in the “On” position.

Additionally, checking the fuse or circuit breaker that powers the Weed Eater’s electrical outlet are plugged in is practical to ensure no problem exists with the electric power.

If a breaker has tripped or a fuse has blown, reset the breaker or replace the fuse.

Battery issues

While battery-powered weed eaters rarely fail, a battery can degrade to the point where it can’t provide sufficient charge for the electric weed eater to start. Therefore, you should also inspect the charge to ensure it works properly. To do this, plug in the battery and check to see if it is charging.

Debris Clogging Line

If you have a battery-powered or electric Weed Eater trimmer that won’t start, turn the power switch to the “off” position and check the bottom of the trimmer. If grass or debris has clogged around the trimmer’s cutting line, the trimmer may not start. Clear all material from the underside of the trimmer to resolve the problem.

Black and Decker weed eater running but not cutting

The most common cause of this is the automatic feeding system. the automatic feed may stop working if the head is tapped or the centrifugal force of the automatic feed system pushes the line out of its alignment.

Since most operating systems are the same, the auto-feed system is not working due to a clog that prevents the line from coming out. Therefore, removing the clog and checking on the feeding system are the most common solutions to these problems.

The most common cause of the Black and Decker Trimmer auto-feed not working is a jammed line within the spool.

Below are the main reasons why the auto-feed system is not working;

Incorrectly wound spool

Since the automatic feed spool system works using centrifugal force, if the spool is wound the wrong way, the spool won’t unwind and feed properly. An arrow marked on the spool indicates the correct direction to wind the line, as well as instructions specific to your model in your use and care guide.

The first thing to check is that the spool is wound and installed correctly. Next, check the use and care guide for your weed eater model and ensure that you are using the correct string diameter. Using the incorrect size can cause wear on the lever of the feed system.

Jammed Line

The line should smoothly come out and be winded tightly to prevent this from happening. Ensure that the line is not trapped inside the spool. You will need to remove the spool and open the cap to ensure the line is properly installed and not stuck. The spool should be wound neatly and evenly. If you notice the line is loose or bulging in certain areas, this can also cause issues with the feeding line. Also, be sure the line is wound in the right direction.

Also, avoid overlapping the lines since it can cause the lines to aggregate and clog the spool. The spare line from Black and Decker has a specific diameter, which can also cause the line to jam if the size does not fit the spool.

Buy the recommended line from the user’s manual and use it to replace the old line on the spool.

Sticky Spool

If a jammed line is not the issue, another cause of the problem may be found on the spool. Any foreign object, dirt, or mud can cause the line on the spool to stick onto it.

Thus, even though you have bumped the head, the automatic feed system will not work. In this case, clean the spool with a detergent that you use normally and rinse it with warm water.

Incorrect Trimmer Use

In some cases, the feeding line may not work because of how you use the trimmer. For example, using the trimmer to do edging can cause the line to kink, interfering with proper line feeding. To fix this, turn off the trimmer and open up the spool. Pull out about 2 inches of line and then replace the spool.

If you run into this issue, make adjustments to the way you are operating the trimmer. For example, using it as an edger can help to allow more space between the trimmer and the ground. This prevents the line from getting too short and kinking.

Broken Spool

Aside from having a dirty spool, one of the problems that may cause your Black and Decker Trimmer Auto Feed not to work is that it is broken. Cracks and unexpected openings can also break the automatic feed system.

The spool is the guide of the line, so it needs to spin appropriately on the head, and if it is bent or has cracks, the line will not come out.

To fix this problem, you can only buy a replacement Black and Decker spool from your local garden store that sells. Make sure you buy a spool that fits your Black and Decker Weed Trimmer.

Broken Spring

Broken and dirty spools are not the only cause of this problem. The spring under the spool may also be bent or has lost its spring ability. If the spring breaks, the spool will stay on the head.

Another thing is that the spring may not be connected to the spool properly, so it cannot perform the work it needs. Try pushing the spool against it now and then to check if it still has its resistance. If the resistance of the spring is not enough for the spool not to work, you may need to replace it with a new one.

How to restring a Black and Decker weed eater

Keep reading to learn how to restring your weed eater;

Items needed

  • 0.065-inch monofilament string, 20 feet
  • Tape measure
  • Scissors

Note: a heavier line won’t advance properly, and the machine could suffer damage if you use it.


  • Unplug the trimmer or remove the battery. Sit on a bench, turn the trimmer over and hold the shaft with your legs to stabilize it.
  • Remove the cap from the trimmer head by depressing the two tabs on the sides with your fingers and lifting it off. Next, lift out the spool and pull off all the old string.
  • Prepare a length of 0.065-inch monofilament string 20 feet long, using a tape measure to measure its length and a pair of scissors to cut it from a roll.
  • Insert one end of the string in one of the two holes in the spool’s hub and wind the string in the direction of the arrow imprinted on the top.
  • Stop winding when you have about 6 inches of string left on end. Hook the string into one of the two notches on the rim of the spool.
  • Replace the spool with the trimmer head, feeding the end of the string through the hole in the side of the head as you do. Set the spool on the pinion and rotate it until it seats properly.
  • Set the cap back on top of the head and push it down to lock it in place.


  1. If you need extra cutting power for tough weeds, use a 0.065-inch braided string instead of a smooth one.
  2. You can move the guard to make replacing the string easier, but if you do, ensure it’s back in its proper position before using the trimmer.

How to thread a Black and Decker weed eater spool

Follow these steps to rethread your weed eater’s spool;

  • Turn off all power to your trimmer. To safely replace the line on your power trimmer, it mustn’t turn on while you work on it.
  • Unplug the trimmer or remove the ion battery that came with it. This will ensure that you won’t accidentally turn on the trimmer and injure yourself.
  • Set the trimmer on top of a table or a chair so that you don’t have to bend over constantly to work with it and easily replace the parts.
  • Remove the cap on the trimmer head. There will be a cap that covers your line on your Black and Decker trimmer.
  • To remove this, use your fingers to press the tabs on both sides of the cap.
  • Once the tabs are pressed, lift on the trimmer cap to remove it and expose the spool underneath.
  • Pull the spool from the cap. Turn over your cap to reveal the line and spool. Two indentations or eyelets on the side of your cap that helps hold the line in place.
  • Pull your line free from the holes on the cap, then grab onto the spool and carefully wiggle it free from the cap.
  • Remove the old line from the spool. Lift it from the eyelets that hold it in place and pull the free end of the line.
  • This will result in removing the old string. Next, repeat the process on the other side of the spool to remove all of the old lines.
  • Wear gloves when working with your trimmer.
  • Thread your new line into the holes designated on your spool. Then, purchase a .080-inch (2.0 mm) diameter round monofilament line from a hardware store.
  • Do not use a serrated or heavier line because it can overload the motor and cause overheating.
  • You can also buy pre-threaded spools from Black and Decker’s website or some hardware stores.
  • Wind the line around the spool, following the arrows on the spool. Then, feed the line through the hole and wrap it around the spool.
  • The more you overlap your spool, the more likely it is to get tangled when you start working with it.
  • Wrap the spool, so the line is wrapped next to itself, not over itself.
  • Most Black and Decker models will have you wrap the string counter-clockwise.
  • Secure the line to the spool and cut the line.
  • Allow 6 inches (15.24 cm) of slack on the end of your line after wrapping it around the spool.
  • Cut the thread with gardening shears or sharp scissors and put the excess line through the eyelets on the spool to hold them in place.
  • Thread and wind the other side of the spool. Then, repeat the steps to wind up and secure the other line on your spool.
  • Follow the arrows when you are winding up the line.
  • Set the spool into the cap. Make sure that the eyelets on the cap and the spool are also lined up.
  • Line up the hole in the center of the spool with the center of the cap and gently press the spool back into the cap.
  • Once you hear a click, turn the cap over and shake it to ensure the spool is secure.
  • Lace the line through the eyelets on the cap.
  • Pull the excess line out of the eyelets on the spool. And push them into the eyelets on the cap.
  • Your spool is now ready to go back into your trimmer.
  • Line up the tabs on the cap and trimmer head and press down.
  • Press the side tabs on your cap down to fit it into the trimmer head.
  • Lightly press on the cap until you hear a click. Your spool is now replaced.

Note: While these steps will help you replace the line on most Black and Decker trimmers, your model may be old or have a different feeding method for your line. The safest way to see if your model differs is by reading the instruction manual or visiting Black and Decker’s support page.

How long does a Black and Decker weed eater battery take to charge?

According to the manufacturer, completing the first charge will take nine hours. After the first charge, subsequent charging will take between six and nine hours. The battery will require an initial charge of six hours when using the Black & Decker VP130 or VP131 battery chargers. After that, recharging varies between three and six hours. When using the larger VP160 battery charger, the recharge time is one hour per battery.

Note: Before its first use, the weed eater’s battery must be fully charged. A green LED light will illuminate and go off when charging is complete. The battery is then ready to be removed from the charging base and placed inside the cavity that houses the battery. When you hear a click, it is securely seated. To begin cutting, put the switch in the “On” position and squeeze the trigger.

How long does a Black and Decker Weed Eater battery last?

The battery will last about 20-30 minutes of operation before needing to be recharged.

How to recharge your weed eater’s battery

To recharge the lithium battery, you first need to remove it from the Black + Decker string trimmer. Look for a large battery-release button on the top of the battery pack if you hold the string trimmer vertically. Press the button in and slide the pack upwards out of the trimmer.

Slide the battery into the charger base; it only fits in one way, which may vary slightly depending on the battery and the charger models. Next, plug the charger base into the wall and wait for its lights to illuminate. A flashing green LED means the battery is charging; if you see nothing, remove the battery and insert it into the pack again, ensuring it’s fully pressed down in place.

The green LED switches from flashing to solid green when the battery is fully charged. At this point, the battery may be removed or left on the charging base, but unplugging it at this stage saves a little electricity versus leaving it plugged in.

How to take care of a cordless Black and Decker weed eater

To extend the life of your trimmer, keep it maintained for the best use. Regular maintenance on a weed trimmer keeps the machine running well for easier weed control.

  • Keep the unit free of debris build-up by wiping down the underside of the guard with a clean, damp cloth.
  • Keep the air intake slots clean to avoid overheating.
  • Your trimmer line can dry out over time. To keep your line in top condition, store spare pre-wound spools or bulk lines in a plastic, sealable bag with a tablespoon of water.
  • Plastic parts may be cleaned using mild soap and a damp rag.
  • The line cutter on the edge of the guard can dull over time. Therefore, you should periodically touch up the blade’s sharpness with a file.

Note: Remove the battery from the tool before performing any maintenance to avoid serious injury. Always wear protective eyewear when operating a trimmer to avoid injury from debris. Be sure the trimmer is cool before cleaning.

How to Clean a Weed Eater

  • Disconnect the power source to the weed trimmer. Remove the battery or unplug the unit. Turn the switch to the off position.
  • Brush loose pieces of dirt, weeds, and grass from the unit using a stiff brush. Move the brush back and forth over stubborn spots.
  • Dip the brush in warm, soapy water if you need additional cleaning power. Scrub the deck and handle of the weed trimmer with soapy water. Dry all parts of the unit after cleaning to avoid damage.
  • Remove the cover over the air filter after every 10 hours of use. Then, wash the filter in soapy water.
  • Rinse the filter with clean water and allow it to air-dry.
  • Coat the air filter lightly with motor oil and squeeze out the extra oil. Put the air filter back in place along with the cover.
  • Pull the spark arrestor out of the muffler after every 25 hours of use.
  • Use carbon cleaner on a metal spark arrestor and a wire brush to clean away grime. Put the piece back in the unit.
  • Remove the weed trimmer’s spark plug using a socket wrench.
  • Clean dirt and debris from the spark plug using brake cleaner.
  • Reconnect the spark plug if the tip is still intact and not black.
  • Replace the spark plug if it is black or if the tip isn’t intact.
  • Connect the power to the weed trimmer after all cleaning is done.
  • Test the unit to ensure the components were replaced properly.

Note: spraying or dousing the weed trimmer with water can damage. Observe safety precautions while cleaning the unit to avoid accidentally hurting yourself.

How often should I replace my Black and Decker weed eater battery?

The typical estimated life of a Lithium-Ion battery is about two to three years or 300 to 500 charge cycles, whichever occurs first.

Why won’t my cordless Black and Decker weed eater charge?

If your battery is not charging, the charger is rapid flashing, and the battery is warm, it may be too hot- particularly after heavy or continued use. If so, please allow the battery to cool, then reinsert the battery on the charger to try charging again.

If you are experiencing charger failure, your batteries should be tested for correct voltage. When a charger fails, it could be because one of the batteries has a shorted cell, which can put an excessive load on the charger, causing it to fail.

The batteries can be tested at any Black and Decker service center. The batteries can also be tested using a digital multimeter. To test the battery, it should be charged on a good Firestorm three-hour charger (do not use any other charger). After that, the battery only needs to be put on the charger for two minutes (this will not damage the charger if only done for two minutes).

After charging for two minutes, its nominal voltage should be reached (example: 9.6 volts will read 9.6 volts). Batteries that do not reach their potential voltage will have a shorted cell. Therefore, a battery that has a shorted cell should not be used.

The Black and Decker weed eater string keeps unwinding

Your Black and Decker trimmer feeds too much line because there’s a malfunction with the auto-feed lever. The auto-feed liver regulates the amount of line that feeds out. As a result, the auto-feed lever gets a lot of use and can wear out over time, leaving too much line.

Reasons why your Black and Decker Trimmer feeds too much line, include:

1. Auto-Feed Lever Trouble

The auto-feed lever sees a lot of use. Since this is the part that regulates the feed of your line, it makes sense that this is also the most likely culprit when something goes wrong.

Whether the lever is backward, broken, worn, or cracked, the solution is surprisingly simple.

According to Black and Decker, you can quickly replace your auto-feed lever by following these steps:

  • Remove the spool cover.
  • Take out the spool.
  • Note the orientation of the feed lever. Generally, the narrow, claw-like end faces clockwise.
  • Pull out the auto-feed lever straight out gently with pliers. Be careful not to break it in the process with too much prying.
  • Snap a new lever into place and replace the spool cover.

2. Missing or Broken Spring

When you take the bump cap off of your Black and Decker trimmer, there’s a spring on the inside. The tension from this spring pushed the cap back into place after you bump it to feed more line out.

Compressing a spring causes it to store energy which it will release as it tries to stretch back into its natural form. If the spring is missing or broken, it won’t push the cap back into place. All you need for this repair is a new spring. It goes where the center of the cap sits and is usually attached to the cap itself.

3. Spool Unseated

The spool can come loose on some trimmers. When the piece that holds your line isn’t sitting right, it can cause overfeeding or jam up easily.

To fix it, pop the cap off and reseat the spool. If the spool is broken because of how it was sitting, replace it with a new spool.

4. Too Much Line On The Spool

While it’s possible to re-spool by hand, you can be overzealous. Sadly, when the spool is overfull or too tightly wound, it may try to release some extra line by unspooling more rapidly than usual.

Alternately, too much trimmer line packed into the limited available space can also cause a jam that makes your trimmer useless until you dig it out. Ultimately, this can lead to a lot of wasted line. Since most people choose to re-spool to save money, it’s counterproductive and wasteful when you overdo it.

If you’re unsure how many lines you need or how tight to wind it, that’s a good reason to buy brand-specific replacement spools.

5. Bump Cap / Trimmer Head Jammed

The trimmer head cap, more commonly called the Bump Cap, on a Black and Decker trimmer is a brilliant innovation that allows you to work faster. It feeds out the line by tapping the bottom of your trimmer on the ground, so you don’t need to stop and turn it off to adjust the length every few feet.

Additionally, placing this near the spool means you don’t need an unnecessarily complex system in the handle with an extra trigger or button. The bump cap is the button in this case. Like any button, when it depresses, you can get girt, grass, grit, and other debris along the edges of the mobile centerpiece.

If the bump cap gets jammed into the pressed down position, it will keep feeding. Turn the machine off completely, and clear the obstruction to release the bump cap.

6. Wrong Size Line

It is always vital to read the directions on your Black and Decker trimmer carefully. Although line comes in varying widths, and many spools can fit, that doesn’t mean your machine can accommodate all of them.

A too thick or too thin line can be hard to spot at a glance because all trimmer lines are fairly thin. Check the diameter and replace the spool with the exact recommended size. Using the spool made to fit your brand is a great way to help ensure you have the correct diameter.

7. You Bumped Something

Flip the machine and look to make sure the cap is not broken or loose. Then, please give it a tap to make certain that it’s not jammed as well. You may be distracted if everything else checks out and only happens sometimes. For example, uneven ground or holding the trimmer too low can cause accidental cap taps.

This might seem like a strange solution, but people do bump into things all the time. Accidentally depressing the bump cap as you work around the yard is common, and it’s more likely than a stop-and-start line feeding issue.

If you’re lucky enough for this to be the problem, you only need to be more careful in this case. First, hold the trimmer up a little higher and know how you rest it on the ground.

Other reasons why a Black and Decker trimmer feeds too much line.

  • A broken or cracked trimmer head cap can cause the feeding mechanism to work incorrectly. Replace this part anytime it breaks, cracks, or wears down.
  • When you have an automatic trimmer, the system that lets line out of your trimmers is known as an AFS or automatic feed system, and it monitors the centrifugal force to feed the line at the right time.

Note: Most repairs are simple to make yourself and easy to spot when you turn the machine over. It will come off easily when you need to remove the cap. However, it’s best to call a professional if you can’t spot the problem.

How to rewind the spool on your weed eater;

To install the bulk line, follow the steps below:

  • Unplug the trimmer, or if cordless, remove the battery.
  • Press the release tabs on the line hub cover and remove the cover by pulling it straight off.
  • Remove the spool from the tool and remove and discard all lines on the spool.
  • Insert one end of the bulk line into the hole in the spool about 1/2″ (12 mm).
  • Snugly and evenly wind the bulk line onto the spool in the direction of the arrow until the line builds up to the notches in the spool rim. Do not overfill the spool.
  • Insert the line end through the eyelet in the spool hub.
  • Pull the line through the hole to maintain tension. While placing the spool down into the hub with the arrow up.
  • Press the spool down GENTLY and rotate it until you feel it drop into place. (When in place, the spool will turn a few degrees left and right freely).
  • Take care to keep the line from becoming trapped under the spool.
  • Snap the hub cover back on, and turn on the tool. You’ll hear the nylon line being cut automatically to the proper length in a few seconds or less.

Note: Use only the size and type of line recommended in your manual. If you no longer have your manual, you can look it up by your trimmer model number at this link. A bulk line for your trimmer/edger is available at extra cost from your local dealer or most home centers and hardware stores.

How to advance string on a Black and Decker weed eater

As you use your trimmer/edger around the yard, the tip of the string gradually wears down, so the additional string is periodically fed to keep the line at the right cutting length. Different trimmers feed the string differently, so you have options to suit your preference.

  • With bump-feed trimmers, you have to tap the bottom of the trimmer on the ground to release more lines as needed. These are older feed designs and can be a little tricky to operate.
  • EASY FEED trimmers offer a more convenient feeding mechanism that lets you decide how much string you want to be released and then feed an extra line with the push of a button.
  • Auto-feed trimmers like the BLACK+DECKER 7.5 Amp 14-inch Trimmer/Edger features the AFS Automatic Feed System™. They automatically sense when the line needs to be fed and do it all for you to provide uninterrupted operation.

Black and Decker Trimmer Spool Problems

When using just about any string trimmer, minor issues are bound to happen with the string stored on the spool. For example, during use, the trimmer may sometimes stop trimming, which most likely means you’re out of string. However, it may also mean that something has blocked the ability of the spool to dispense the line.

Black and Decker automatic feed spool problems may include a jammed or tangled line, clogs from trimming heavy weeds, or an overheated motor in the trimmer. An overheated motor can be caused by reloading the spool with a line thicker than the size recommended by the manufacturer.

Correcting Feed Spool Jams

If the string trimmer stops feeding the new line or seems to be jammed, unplug the trimmer. Flip the trimmer over so the bottom side faces you, then squeeze the tabs on the feeder spool hub to release the cap or cover. Pull the cap off, then remove the spool.

Check the spool for small pieces of line, plant matter, or other debris that may be causing issues. In some cases, the line itself may be partially tangled, especially if the line was wound by hand. If so, unwind enough line to untangle it, then wind it on the spool again.

Put the spool back in the cap, then feed a small amount of line through the line hole in the cap. Push the spool down and turn it slightly in either direction until it snaps in place. Place the cap and spool assembly back onto the trimmer so the tabs you pressed snapped back into position, locking the entire spool unit.

Note: Always check the manual or company website to ensure the right size and type of line is used, as the trimmer may not function properly.

How to remove the battery from a Black and Decker weed eater

To remove the battery pack, depress the two buttons on either side of the neck of the string trimmer, just below where the battery attaches. Keeping the buttons depressed, slide the battery pack up until the arrow on the housing lines up with the unlocked arrow symbol on the mating part. Now the battery is free to be removed.

To install the battery, line up the molded-in arrow on the battery housing with the pictorial of an unlocked lock on the mating part of the trimmer. Push the two together and slide the battery assembly down so the arrow lines up with the locked lock symbol molded into the mating part. The battery will self-lock into place. It may require some force to install the battery on the trimmer.

How to remove the head from a Black and Decker weed eater

The head is attached to the trimmer with a retaining nut or bolt. Ratchet it free and pull it off (some nuts and bolts will be reverse-threaded).

Removing the old spool doesn’t require any special tools. The most common method is pushing in, twisting, and pulling off the spool. If your trimmer head differs, follow the manufacturer’s instructions to remove the old head.

  • Turn off and unplug the trimmer.
  • Press the tabs on the spool cap and lift it off the trimmer.
  • Grab the spool and spool housing with each hand and pull the spool out of the housing.
  • Clean out any debris from the spool housing with a cloth.
  • Guide the end of the cutting line from the new spool into the eyelet on the spool housing.
  • If necessary, adjust the lever in the spool housing to its original position. Then, place the new spool onto the housing and rotate it slightly until it fits.
  • Pull the line about five 3/8-inches through the housing.
  • Line up the spool cap’s tabs with the housing slots and press it into place until it snaps. Cut off the excess with scissors if any line extends beyond the trimming blade.

Why is my Black and Decker weed eater draining its battery so fast?

Below are possible reasons the weed eater battery is not holding a charge;

Dirty or Corroded Battery Cables

It happens to your automobiles, and it can certainly happen to your weed eater battery. You open up the hood, and a whitish, powdery crust on the battery cables is building up around the terminals.

Hydrogen gas escapes from your battery and reacts with the metal on the battery posts and cables, causing corrosion. If it gets too bad, it will prevent the battery from recharging or sending power to the weed eater altogether. It’s annoying but a simple fix.

How to Fix: Put on your safety gear, chemical-resistant gloves, eye protection, all that stuff. There could be some battery acid, or the corrosion could irritate skin and mess up clothing.

Disconnect the battery terminals, pour baking soda (you can also use battery cleaner from your local auto parts store) around the corroded areas, and then pour a little bit of water on the baking soda to neutralize the corrosion and battery acid.

If the corrosion is stuck, you can use a small wire brush to scrape it off, then use more baking soda and water to dissolve the residual corrosion. Use paper towels to clean and dry the areas, reattach the cables, charge your battery again, and you’re good to ‘mow.’

Loose Battery Cables

If you have a loose connection, then the battery will struggle to keep everything running correctly. In addition, the constant vibrations of the motor over time can cause the bolts to loosen slightly, causing your battery to work overtime to power your weed eater.

How to Fix: Wiggle all the cable connections to see if they are loose. If any need tightening, clamp them down properly, then return to tending your yard.

The Voltage Regulator is Going Bad

If the voltage regulator is going bad, it will cause the battery to drain pretty quickly.

How to Check: You will need your trusty multimeter to check for this problem. Set it to check the voltage, and turn on the weed eater just enough to get a load running through the electrical system. Check the battery terminals with the multimeter.

You are looking for a voltage between 13.8 and 14.5 volts. Below 13.8 means your battery is failing or is not sufficiently charged, and above 14.5 means you have a fault in the voltage regulator that needs to be replaced.

Your Battery is Failing

Another reason your weed eater battery keeps draining could be because it has reached the end of its life cycle and is dying. Weed eater batteries typically have a lifespan between 3 to 5 years with proper care.

Of course, you can get the occasional lemon that doesn’t even tick on that long, but if you can’t find anything else that keeps draining your battery, you might have to consider replacing your old one. The simple fix here is to buy another weed eater battery. Once the battery starts failing, nothing else can be done about it.

Electronic Drain

With all the new advances in everything electronic, your battery could be experiencing a parasitic electronic drain. This happens when the weed eater is turned off, but a small electrical charge is still sucking minute doses of power.

Given time, this could weaken or completely drain the battery. This can be difficult to check for and to fix, but if all other avenues have been exhausted, you may have to check for this. You will need a multimeter for this particular diagnosis.

How to Check: Set your multimeter to ammeter mode, then set the probes on the battery posts when the weed eater is turned off. If you get a reading of more than 1mA, your electrical system is still drawing current off the battery via a relay system or a component in the weed eater with a standby mode.

Check this too: Homelite Weed Eater How to & Troubleshooting Guide

You may have to take it in to get your weed eater serviced to remedy the parasitic drain. You could also disconnect the battery each time to save it from the power-sucking culprit or keep a maintenance charger on the battery when not in use.

How to store Black and Decker lithium batteries for the winter

It is safe to leave your lithium batteries on charge over long periods, but in the case of outdoor usage, you may want to store them away for the winter months. Always top off the charge before storage, then choose a cool, dry place away from direct sunlight.

5 to 25 degrees Celsius or 41 to 77 degrees Fahrenheit is ideal. In addition, lithium batteries will maintain their charge for months at a time, so when the season ramps back up, there is no need to top the batteries off again before using them.