How to Find Your Engine's Top Dead Center (TDC)
Disconnect the battery., Disconnect the plug wire from cylinder one., Remove the spark plug from cylinder number one., Install the piston stop tool into cylinder number one.
Step-by-Step Guide
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Step 1: Disconnect the battery.
Before beginning the project, use a hand or socket wrench to loosen the nut holding the black “ground” cable on the negative terminal of the battery.
Pull the cable up off of the terminal and tuck it to the side of the battery to prevent it from coming back into contact with the terminal until you’re done.Disconnecting the battery will prevent you from shocking yourself or causing any blown fuses while you work.
The car will not be able to start with the battery disconnected. -
Step 2: Disconnect the plug wire from cylinder one.
Refer to your vehicle’s service manual for help identifying which spark plug coincides with cylinder one.
Once you’ve found it, grip the spark plug wire at the base where it connects to the spark plug and pull it backward to remove it.Make sure you check the service manual for your specific year, make and model vehicle.
Do not pull on the spark plug wire itself, but rather from its base, when removing spark plug wires. , Use a spark plug socket and a long extension on your wrench to remove the spark plug in the cylinder one position of your vehicle.
Rotate the plug counter clockwise to unthread it before pulling it out.The spark plug will stick in the spark plug socket thanks to a rubber ring inside it.
Check the spark plug for any signs of damage, then set it aside someplace safe. , Take your piston stop tool and insert it into the spark plug socket you used to remove the spark plug.
Lower it into the same hole you removed the spark plug from, and thread it into place carefully by turning it in a clockwise direction.Be extremely careful not to allow any debris to fall into the spark plug hole as you switch it out for the piston stop tool.
You can purchase a piston stop tool and most auto parts stores.
The piston stop tool doesn’t have to be too tight.
Simply make it snug by hand. -
Step 3: Remove the spark plug from cylinder number one.
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Step 4: Install the piston stop tool into cylinder number one.
Detailed Guide
Before beginning the project, use a hand or socket wrench to loosen the nut holding the black “ground” cable on the negative terminal of the battery.
Pull the cable up off of the terminal and tuck it to the side of the battery to prevent it from coming back into contact with the terminal until you’re done.Disconnecting the battery will prevent you from shocking yourself or causing any blown fuses while you work.
The car will not be able to start with the battery disconnected.
Refer to your vehicle’s service manual for help identifying which spark plug coincides with cylinder one.
Once you’ve found it, grip the spark plug wire at the base where it connects to the spark plug and pull it backward to remove it.Make sure you check the service manual for your specific year, make and model vehicle.
Do not pull on the spark plug wire itself, but rather from its base, when removing spark plug wires. , Use a spark plug socket and a long extension on your wrench to remove the spark plug in the cylinder one position of your vehicle.
Rotate the plug counter clockwise to unthread it before pulling it out.The spark plug will stick in the spark plug socket thanks to a rubber ring inside it.
Check the spark plug for any signs of damage, then set it aside someplace safe. , Take your piston stop tool and insert it into the spark plug socket you used to remove the spark plug.
Lower it into the same hole you removed the spark plug from, and thread it into place carefully by turning it in a clockwise direction.Be extremely careful not to allow any debris to fall into the spark plug hole as you switch it out for the piston stop tool.
You can purchase a piston stop tool and most auto parts stores.
The piston stop tool doesn’t have to be too tight.
Simply make it snug by hand.
About the Author
Heather Hughes
Heather Hughes has dedicated 3 years to mastering lifestyle and practical guides. As a content creator, Heather focuses on providing actionable tips and step-by-step guides.
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