Harley Davidson Shovelhead engines are known for their distinctive sound and impressive power. These engines were produced from the mid-1960s to the mid-1980s and are still popular among motorcycle enthusiasts. One of the most important aspects of maintaining a Shovelhead engine is ensuring that the timing marks are set correctly.
Timing marks are used to set the ignition timing of the engine. This is crucial for proper engine performance, fuel efficiency, and longevity. Incorrect timing can cause engine damage, poor performance, and even dangerous situations while riding. Harley engines have a unique system for Shovelhead timing marks that can be confusing for those who are not familiar with them.
Understanding Shovelhead timing marks is essential for anyone who owns or works on these engines. This article will highlight the different types of timing marks used on Shovelhead engines and how to set them correctly. Whether you’re an experienced mechanic or a new Shovelhead owner, this information will help you keep your engine running smoothly and reliably.
Understanding the Harley Davidson Shovelhead Timing Marks
Setting the timing on a Shovelhead can be a bit of a daunting task, even more so if you’re not familiar with timing marks. Understanding the Shovelhead timing marks is crucial to ensure that the engine runs smoothly and efficiently. Now, we will discuss the different timing marks on a Shovelhead and how to set the timing correctly.
The engine has two Shovelhead timing marks: one for the front cylinder and one for the rear cylinder. The front cylinder timing mark is a dot, while the rear cylinder timing mark is a line. The dot represents top dead center (TDC) for the front cylinder, while the line represents TDC for the rear cylinder.
It’s important to note that the timing marks can change depending on the year and model of the Shovelhead. Some Shovelheads have double lines or double dots, which can cause confusion when setting the timing. Therefore, it is essential to consult the owner’s manual or a reliable source to determine the correct timing marks for your specific Shovelhead.
To set the timing on a Shovelhead, you will need to locate the timing hole on the engine case. The timing hole is a small hole located on the left side of the engine case, near the base of the cylinders. Once you have located the timing hole, you will need to remove the cover and rotate the engine until you can see the timing marks through the hole.
When setting the timing, it is important to follow the manufacturer’s specifications for the ignition system. For example, if you have a points ignition system, you will need to set the points gap and adjust the timing accordingly. If you have an electronic ignition system, you will need to follow the manufacturer’s instructions for setting the timing.
Overall, understanding the timing marks on a Shovelhead is essential for proper engine performance. By following the manufacturer’s specifications and consulting reliable sources, you can ensure that your Shovelhead runs smoothly and efficiently.
Locating the Timing Marks
Locating the Shovelhead timing marks on a Shovelhead engine is crucial for proper engine performance. The timing marks are used to set the ignition timing, which determines when the spark plugs fire, and the fuel mixture ignites. There are different timing marks on the Shovelhead engine, and it’s important to know which ones to use for proper timing.
The timing marks on a Shovelhead engine are located on the flywheel and the camshaft. The flywheel timing marks indicate the position of the pistons, while the camshaft timing marks indicate the position of the valves. The timing marks are typically located behind a timing hole cover on the engine case.
When locating the timing marks, it’s important to rotate the engine in the correct direction. The Shovelhead engine rotates clockwise when viewed from the right side of the motorcycle. To rotate the engine, use a wrench on the crankshaft bolt or use the Kickstarter on kickstart models.
Once the engine is rotating in the correct direction, locate the timing marks through the timing hole cover. The front cylinder timing mark is typically a dot or a line, while the rear cylinder timing mark is typically a double dot or a double line. Some Shovelhead engines may have different timing marks, so it’s important to consult the manufacturer’s manual or a reputable mechanic for guidance.
Setting the Timing Marks
Setting the Shovelhead timing marks on a Shovelhead engine is a crucial step in ensuring optimal performance. Here are the steps to follow:
- Set the gap of the points to about .018″.
- Bring the front cylinder up on compression by watching for the intake tappet to close.
- Rotate the engine slowly until the advance mark for the front cylinder is visible through the timing hole.
- Continually rotate the engine slowly until the TDC mark is just visible on the back lower edge of the timing hole.
- Rotate the backing plate until the points just begin to open.
- Grasp the point cam in the center of the timing mechanism and twist it counterclockwise until it stops.
- Hold the point cam in that position while moving the points plate counterclockwise until the test lamp lights.
As mentioned previously, the marks on Shovelhead engines can vary; this is due to different years and models. Some models have a double line for the rear cylinder timing mark, while others have a dot. The front cylinder timing mark can also be a dot or a line. We recommend consulting the owner’s manual or a trusted mechanic to ensure proper timing mark identification and adjustment.
Additionally, the timing marks should be checked and adjusted periodically to ensure optimal performance and prevent engine damage. Regular maintenance and inspection are key to keeping your Shovelhead running smoothly.
Common Issues with Harley Davidson Shovelhead Timing Marks
Setting the timing on a Harley Davidson Shovelhead is difficult at the best of times, even for experienced mechanics. We’ve listed out some common issues that can arise when dealing with Shovelhead timing marks:
One of the most common issues is the confusing nature of the marks themselves. In some cases, there may be multiple marks on the flywheel, making it difficult to determine which one to use. Additionally, the marks themselves may be difficult to see or may have faded over time, making them even harder to locate.
Another issue that can arise is incorrect timing. This can happen if the marks are not properly aligned or if the timing is set too far advanced or retarded. Incorrect timing can lead to poor performance, reduced power, and even engine damage.
Over time, the parts that control the timing on a Shovelhead may become worn or damaged. This can lead to inconsistent timing or difficulty in setting the timing properly.
If you come across any of these problems, it is important to address them as quickly as you can to avoid damaging your engine. If you’re stuck, don’t be afraid to go to a mechanic or refer to your Harley Davidson service manual for guidance on setting the timing correctly.
Final Words On Shovelhead Timing Marks
Setting the timing on a Harley Davidson Shovelhead engine can be a bit confusing, especially with the variety of marks and dots used throughout the years. With your new-found knowledge and some patience, you will be able to easily set the Shovelhead timing marks.
When setting the timing on a Shovelhead engine, it is important to use the correct timing mark for the specific year and model of the engine. As we have seen, the Shovelhead timing marks varied throughout the years, with some engines using dots and others using lines to indicate TDC and advance.
It is also important to use the correct ignition system when setting the timing. Different ignition systems may require different timing marks to be used, so it is important to consult the manufacturer’s instructions when installing a new ignition system.
Finally, it is important to take your time when setting the timing on a Shovelhead engine. Rushing the process or using the wrong Shovelhead timing marks can result in poor performance or even engine damage. By following the correct procedures and using the correct Shovelhead timing marks, you can ensure that your Shovelhead engine runs smoothly and reliably for years to come.