Free a Frozen Parking Brake

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A frozen parking brake (also called a hand brake or emergency brake) is going to cause a delay, but it can be “thawed” easily. Unlike the “regular” (hydraulic) brake system on most vehicles, the parking brake is a purely mechanical system. It is operated by springs and cables inside a sheath. Water can become trapped in the sheath and freeze solid if it is cold enough. This ice prevents the cable from sliding inside the sheath as designed.

Steps

Dislodging Ice

  1. Start the vehicle. Turn the key and start your vehicle. This will start warming up all of the car's components via heat from the engine and exhaust. It usually takes around ten minutes for the engine to warm up, but that does depend on the outside temperature.[1] Revving the engine will speed up the process.
  2. Release and set the parking brake repeatedly. This is the easiest way to dislodge ice from your parking brake.[2] It also has the added benefit of not requiring that you get out in the cold. If you have given your car time to heat up as suggested above, and tried five or ten times to release the brake without success, you should consider trying to tap the ice off of the brake.
  3. Tap the parking brake lightly. Consult your service manual to see which wheels the parking brake holds. Try gently tapping the brake drum or caliper with a hammer or mallet to dislodge any ice. You can put cardboard or a block of wood between the hammer and your bake components, though this is not necessary. You can also try gently wiggling the brake cable in an attempt to dislodge ice.

Melting Ice

  1. Locate an appropriate heat source. A heat gun or hair dryer will usually work, but you may have to run an extension cord out to your vehicle. Another option is to use hot water, but be conscious of the current temperature. If it is still below freezing, you should not use water as it may refreeze.
  2. Apply heat to the brake components. Look at your service manual to see which wheels the parking brake holds. Then use your heat source to apply heat to the brake cable and the calipers/drums at that wheel. You should apply the heat long enough for the brake components to be warm to the touch. The amount of time this takes will vary based on how cold it is outside.
    • This will have to be done from underneath the vehicle so you may need to lift your car.
    • For safety reasons, you should turn off your engine and chock your wheels before getting under the car.
  3. Try to release your brake. After applying heat to the brake system, immediately try to release the brake. Do not give the braking components time to refreeze.

Melting Ice with Engine Heat

  1. Roll all of your windows down. You will be blocking off the spaces under the car, and running the risk of putting excess carbon monoxide into your car. You should roll your windows down and turn your fan on high to allow circulation.
  2. Create a “tunnel” underneath the car. Shovel Snow or arrange other materials along the sides of the vehicle to block as much of the open space between the ground and sides of the vehicle as possible. The objective is to give the heat created by the engine a path to the rear of the vehicle where most of the parking brake components are located.
  3. Allow the vehicle to warm up. Wait outside the vehicle while it is running. You want to allow the engine time to warm up and produce the heat necessary to melt any ice underneath the car.
  4. Attempt to release the brake again. If still frozen, allow more time for thawing and/or block open spaces at the front and rear of the vehicle, too (this is particularly helpful if it is gusty or windy). Pushing down the accelerator slightly will increase heat by working the engine harder.
    • Leave your door open while pressing the accelerator and then get back out of the car. If you have any exhaust issues at all, or have the exhaust blocked off, you run the risk of filling the car with carbon monoxide. This can be deadly.
  5. Take down your “tunnel." Once the ice has thawed, you can remove the walls that you created to block the underside the car.
  6. Allow the cab to ventilate before driving. Leave your windows down and your fan on high and allow the cab to displace any possible carbon monoxide buildup before sitting in the cab or driving. Again, carbon monoxide is deadly.

Preparing to Replace a Defective Brake Cable

  1. Purchase a replacement cable from a local parts dealer. Park brake cables sometimes become corroded or get dirt and grim in them. If this happens, it can cause your brake to get stuck and not function properly. Your best option is to replace the cable.
  2. Pull the car onto level, solid ground. It is important that your car does not sink or roll away while resting on a jack or on jack stands.
  3. Remove hubcaps from the wheels you will be working on. Consult your service manual to see which wheels are held by the park brake. If any of the wheels you will be working on has hubcaps, use a wrench or screwdriver to remove them.
  4. Loosen the lug nuts with a lug wrench (tire iron) or impact wrench. It is important to remember to loosen, or break, the lug nuts before you jack up the vehicle. This way the weight of the vehicle is still on the wheels and it prevents them from spinning dangerously while you turn the lugs.
  5. Jack up the car. Once the lugs have been loosened, it will be necessary to jack the car up so that the wheels can be removed. As mentioned above, this should be done on level concrete or some other hard, level surface. Some important things to remember when jacking up the car are:
    • Your owner’s manual will recommend jacking points
    • The most common way to elevate the car is a floor jack or trolley jack.
    • You should use jack stands to stabilize the car.
    • If you have access to a hydraulic lift, it will save you time.
  6. Remove the wheels. At this point, the lugs may be loose enough to remove by hand. If not, finish removing the lugs with the lug wrench or impact wrench. Once the lugs are removed, pull the wheel off of the wheelbase. Place wheels under the car as back-up protection in case the jack stands fail.
  7. Remove the grease dust cap. This cap will be in the center of the hub and can be removed by simply prying away from the hub. This will expose the retaining nut.[3]
  8. Pull out the cotter pin. There will be a pin in front of the retaining nut that prevents the nut from loosening (referred to as a cotter pin). Remove it by straightening the bent end of the pin and prying it out of its hole with pliers or a screwdriver.[4]
  9. Remove the retaining nut. Using a wrench or ratchet, turn the nut counter-clockwise (to the left) to loosen it. If the nut is stuck, lubricate it with WD-40 or similar lubricant.
  10. Inspect the drum. Some drums have small bolts holding them to the hub. If this is the case, you will need to remove those bolts. [5]
  11. Attempt remove the drum. Pull the drum straight off of the hub. You may have to wiggle a little to get it started. If the drum appears stuck and will not pull off, you should:
    • Check to make sure all bolts holding the drum to the hub are removed.
    • Check to see if the drum is getting caught on the brake shoes.[6]
  12. Retract the brake shoes. This step is only necessary if your drum is getting caught on the brake shoes. You will need to look on the back side of the backing plate (the steel plate on which the brake components are mounted) for a small rubber plug. Removing this plug will provide access to the brake shoe adjuster. Use a flat head screwdriver or a brake adjuster bar to retract the brake shoes.
    • The adjuster is designed to self-adjust the shoes into a tightened position, so loosening them may be tricky. If the drum gets harder to turn as you adjust, you are going in the wrong direction.
    • Once the shoes are retracted, you can remove the drum and continue.

Removing the Cable

  1. Remove the return springs. These springs attach to the brake shoe and the shoe anchor and hold tension on the brake shoe. Once the brake pedal is released, they return the brake shoe to its original position. To remove them, use the round part of the brake tool with a little notch. Place the round part on the anchor pin (the nob that the springs are hooked to) and turn it until the notch catches the spring, and then twist and pull to remove the spring.[7]
  2. Remove the retaining rings that hold the brake shoes in place. To do this, lightly grip the outside of the retaining ring with pliers, push in, and twist until the ring comes off.[8]
  3. Pull the brake shoe off. At this point the shoe should easily pull away from the backing plate. There will be another spring attached at the bottom of the shoe, but it will no longer be tensioned so you can just slide it off of the shoe.
  4. Remove the emergency brake line. One of the brake shoes will be connected to an emergency brake line. To remove it, pull the spring cover back and slide the cable sideways away from the shoe.[9]
  5. Slide the emergency brake line out of the backing plate. There will be a hole in the backing plate where the emergency brake line comes in from under the car. Use a flat screwdriver to depress the tabs on the brake cable that hold it in the backing plate and then pull it through the hole.
  6. Follow the length of the cable back to the brake lever. Whether your brake is operated by a hand lever or a foot pedal, it will connect to the brake cable. Once you find this connection, use a flathead screwdriver to release the cable from its clip. Now that the cable is loose on both ends, you are ready to install your new cable.

Installing the New Cable

  1. Grease the new cable. It is important to lubricate the cable before installation to ensure that it works properly.
  2. Connect the new cable to the park brake lever. Connect the front end of your new cable to the lever assembly by sliding it into the same clip that held the old cable.
  3. Run the cable to the backing plate. Be sure to fasten the cable to the body of the vehicle whenever called for in your service manual. You want to keep the correct amount of tension on the cable at all times to ensure that it functions properly. Slide the cable into the hole in your backing plate.
  4. Connect the new brake line to your brake shoes. Fasten the emergency brake cable to the brake shoe on the same side you removed it. To do this, pull up the cover and slide the cable into the proper slot on the shoe (it will look the same as the one you removed from it).[10]
  5. Grease the backing plate. You want to avoid squeaking and rubbing of the brake shoes. For this reason, you should grease any bare or rubbed spots on the backing plate.[11]
  6. Slide the bottom spring onto the brake shoe. There will be a hook at the end of the spring and a slot in the bottom of the brake shoe. Hook the spring into that slot.
  7. Slide the shoe into place against the backing plate. Now it is time to put the first brake shoe back into place. Once you get it lined up, hold it there until you can replace the retaining ring.

Putting it All Back Together

  1. Replace the retaining ring for the first shoe. Put the spring that goes with the retaining ring in place over the small rod that protrudes from behind the brake shoe. Place the ring over the spring, press in and twist until the ring slides over the rod and locks into place.
  2. Slide the bottom spring onto the second brake shoe. Now, it is time to begin installing the second brake shoe. Again, you are going to start with the bottom spring.
  3. Put the brake shoe into its proper place against the backing plate. You will need to line it up with the adjusting spring lever.
  4. Fasten the adjusting spring onto the second brake shoe. Use the flat end of your brake spring tool to pry the spring into place and hook it at the top of the second brake shoe. This will connect the two brake shoes.
  5. Replace the retaining ring for the second shoe. Follow the same procedure as you did with the first retaining ring. Place the spring first, then push and twist the ring into place.
  6. Use two screwdrivers to set the adjusting screw. This screw changes the position of the adjusting spring, which in turn changes the position of the brake shoes. Since the new shoes are thicker than the old ones, you will need to set the adjusting screw to account for that. Use one screwdriver to push the automatic adjuster assembly down and the other to twist the cog that loosens the adjuster.
  7. Put the drum back on. Slide the drum back onto the hub. You will want to spin it and make sure that it has just a little drag. If the drum does not spin then your shoes are too tight and you need to loosen them (using the adjusting screw). If the drum spins freely with no drag at all then your shoes are too loose and you will need to tighten them (using the adjusting screw).
  8. Replace any bolts that hold the drum to the hub. You may or may not have bolts to fasten your drum to the hub. If you do, they should be reinstalled now.
  9. Reinstall the retaining nut and cotter pin. You want to tighten the retaining nut that holds the drum in place, and also put the cotter pin back through the hole to keep the nut from loosening.
  10. Put the dust cap back on. The dust cap should push right back into place. Make sure that it is snapped back into place tightly.
  11. Re-install the wheels. You should slide the wheels back onto the wheelbase and thread the lug nuts on tight enough to hold wheels in place while the car is still on the jack stands.
  12. Remove the jack stands and lower the vehicle to the ground using the floor jack. Do this slowly and carefully. You do not want the vehicle to drop suddenly.
  13. Tighten the lugs to the specified torque. Once the weight is back on the wheels, use a lug wrench or impact wrench to tighten the lugs to the proper torque specifications in your service manual.
  14. Add brake fluid if needed. You should check your brake fluid and add more if needed anytime you do brake work.
  15. Test the brake. Before you drive or park your car, you want to be sure that your park brake is working properly. Set the park brake and put the car into drive. The brake should hold the car still, or at the very least provide resistance. Release the brake and make sure that the resistance is gone.

Tips

  • If the temperature is going to be below 32°F (0°C) for extended periods of time, it may be advisable to avoid using the parking brake if this can be done safely.
  • When parking the vehicle, leave a standard transmission in gear and an automatic transmission in park.
  • Turn wheels towards the curb if parked pointing downhill or away from the curb if pointing uphill so that the car’s front wheel rests against the curb.

Warnings

  • Minimize time spent inside the car while running. With the spaces under the vehicle blocked off, any exhaust leaks in the engine compartment or along the exhaust system can more easily work their way into the cabin—potentially causing carbon monoxide poisoning. Before entering the car, after it has been idle for several minutes, make sure that the cabin is ventilated to remove any build-up of exhaust fumes. Carbon monoxide is colorless and odorless, and inhaling it can be fatal.
  • Make sure that the end of the exhaust pipe is not obstructed in any way, and that the exhaust gases from it cannot become trapped under the vehicle.

Related Articles

Sources and Citations

  1. ↑ http://www.popularmechanics.com/cars/a19086/warming-up-your-car-in-the-cold-just-harms-engine/
  2. ↑ http://www.dbausa.com/whats-that-noise/
  3. ↑ http://www.allpar.com/fix/brake-drums.html
  4. ↑ http://www.allpar.com/fix/brake-drums.html
  5. ↑ http://www.allpar.com/fix/brake-drums.html
  6. ↑ http://www.allpar.com/fix/brake-drums.html
  7. ↑ https://www.youtube.com/watch?v=MIyESaecC2s
  8. ↑ https://www.youtube.com/watch?v=aaJ6X-uxMGM
  9. ↑ https://www.youtube.com/watch?v=aaJ6X-uxMGM
  10. ↑ https://www.youtube.com/watch?v=aaJ6X-uxMGM
  11. ↑ https://www.youtube.com/watch?v=aaJ6X-uxMGM
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