Dwell is the amount of time a spark plug’s points are closed, allowing current to flow through the coil and generate a spark. Dwell is measured in degrees of crankshaft rotation and is typically between 25 and 45 degrees. Checking dwell is important because it can help you identify problems with your ignition system, such as a weak coil or faulty points.
The importance of dwell cannot be overstated. A properly set dwell will ensure that your engine runs smoothly and efficiently. If the dwell is too short, the spark will be weak and the engine will misfire. If the dwell is too long, the coil will overheat and the points will burn out.
There are two main ways to check dwell: with a dwell meter or with a timing light. Using a dwell meter is the most accurate method, but it can be more difficult to use. Using a timing light is easier, but it is less accurate.
1. Tools
A dwell meter or timing light is an essential tool for checking the dwell angle because it allows you to measure the amount of time that the points in the distributor are closed. This is important because the dwell angle affects the strength of the spark and the timing of the ignition. If the dwell angle is too short, the spark will be weak and the engine will misfire. If the dwell angle is too long, the coil will overheat and the points will burn out.
Using a dwell meter or timing light to check the dwell angle is a relatively simple procedure. However, it is important to follow the instructions in your vehicle’s service manual carefully.
Checking the dwell angle is an important part of maintaining your vehicle’s ignition system. By ensuring that the dwell angle is set correctly, you can help to prevent engine problems and keep your vehicle running smoothly.
2. Safety
This safety precaution is crucial when checking the dwell because the ignition system is powered by the battery. If the negative terminal of the battery is not disconnected, there is a risk of electrical shock or fire. This is because the dwell meter or timing light that is used to check the dwell creates a circuit between the battery and the ignition system. If the negative terminal of the battery is not disconnected, this circuit can be completed through the body of the person performing the test, resulting in an electrical shock.
In addition to the risk of electrical shock, there is also a risk of fire if the negative terminal of the battery is not disconnected. This is because the dwell meter or timing light can create a spark that could ignite flammable materials in the engine compartment. Therefore, it is important to always disconnect the negative terminal of the battery before working on the ignition system, including when checking the dwell.
By following this safety precaution, you can help to prevent accidents and injuries when working on your vehicle’s ignition system.
3. Procedure
Checking the dwell is a relatively simple procedure, but it is important to follow the instructions in your vehicle’s service manual carefully. The service manual will provide you with specific instructions on how to connect the dwell meter or timing light, and how to interpret the results. By following the instructions in the service manual, you can ensure that you are checking the dwell correctly and that you are getting accurate results.
- Using the correct tools: The first step in checking the dwell is to make sure that you are using the correct tools. You will need a dwell meter or a timing light, and you will also need to consult your vehicle’s service manual to determine which type of tool is required.
- Connecting the dwell meter or timing light: Once you have the correct tools, you will need to connect them to your vehicle’s ignition system. The dwell meter or timing light will typically have two leads, one that is connected to the negative terminal of the battery and one that is connected to the ignition coil.
- Interpreting the results: Once the dwell meter or timing light is connected, you can start the engine and check the dwell. The dwell meter will display the dwell angle in degrees, while the timing light will flash at the moment that the points open. By comparing the dwell angle to the specifications in your vehicle’s service manual, you can determine if the dwell is set correctly.
Checking the dwell is an important part of maintaining your vehicle’s ignition system. By following the instructions in your vehicle’s service manual, you can ensure that the dwell is set correctly and that your vehicle is running smoothly.
FAQs about How to Check Dwell
Here are some frequently asked questions about how to check dwell, along with their answers:
Question 1: What is dwell?
Answer: Dwell is the amount of time that the points in a distributor are closed, allowing current to flow through the coil and create a spark.
Question 2: Why is it important to check dwell?
Answer: Checking dwell is important because it can help you identify problems with your ignition system, such as a weak coil or faulty points.
Question 3: What tools do I need to check dwell?
Answer: You will need a dwell meter or a timing light to check the dwell.
Question 4: How do I check dwell?
Answer: Follow the instructions in your vehicle’s service manual to check the dwell.
Question 5: I don’t have a dwell meter or a timing light. Can I still check dwell?
Answer: You can estimate the dwell by using a voltmeter to measure the voltage at the coil. The voltage should be between 6 and 12 volts when the points are closed.
Question 6: What should I do if the dwell is not set correctly?
Answer: If the dwell is not set correctly, you should adjust the points or replace the coil.
Checking dwell is a simple procedure that can help you keep your engine running smoothly. By following the steps in this FAQ, you can ensure that your dwell is set correctly and that your vehicle is running at its best.
Moving on to the next article section…
Tips for Checking Dwell
Checking dwell is a simple procedure that can help you keep your engine running smoothly. By following these tips, you can ensure that you are getting the most accurate results and that your vehicle is running at its best.
Tip 1: Use the correct tools.
The first step in checking the dwell is to make sure that you are using the correct tools. You will need a dwell meter or a timing light. Consult your vehicle’s service manual to determine which type of tool is required.
Tip 2: Follow the instructions in your vehicle’s service manual.
Each vehicle is different, so it is important to follow the instructions in your vehicle’s service manual when checking the dwell. The service manual will provide you with specific instructions on how to connect the dwell meter or timing light, and how to interpret the results.
Tip 3: Make sure that the engine is running smoothly.
The dwell should be checked with the engine running at idle speed. If the engine is not running smoothly, the dwell reading may be inaccurate.
Tip 4: Check the dwell at both high and low RPMs.
The dwell should be checked at both high and low RPMs to ensure that it is set correctly across the entire RPM range.
Tip 5: If the dwell is not set correctly, adjust the points or replace the coil.
If the dwell is not set correctly, you should adjust the points or replace the coil. Consult your vehicle’s service manual for specific instructions on how to do this.
By following these tips, you can ensure that the dwell is set correctly and that your vehicle is running at its best.
Moving on to the article’s conclusion…
In Closing
Checking dwell is a simple but important procedure that can help you keep your engine running smoothly. By following the steps outlined in this article, you can ensure that your dwell is set correctly and that your vehicle is running at its best.
If you have any questions about how to check dwell, please consult your vehicle’s service manual or a qualified mechanic. Checking dwell is a relatively simple procedure, but it is important to follow the instructions carefully to ensure that you get accurate results.
