How To Time A D16 Cam

Timing a D16 cam is a critical step in ensuring optimal performance and longevity of your engine. The D16 cam, found in Honda D-series engines, is responsible for controlling the opening and closing of the intake and exhaust valves. Proper timing of the cam ensures that the valves open and close at the correct time, allowing the engine to breathe efficiently and produce maximum power. Neglecting to time the cam accurately can lead to a range of engine problems, including reduced performance, increased fuel consumption, and even engine damage.

The process of timing a D16 cam requires precision and attention to detail. It involves setting the camshaft to the correct position in relation to the crankshaft, ensuring that the valves open and close at the desired moments in the engine’s combustion cycle. To achieve accurate timing, it is essential to use the correct tools and follow the manufacturer’s specifications carefully. This article will guide you through the steps involved in timing a D16 cam, providing detailed instructions and helpful tips to ensure a successful outcome.

Before embarking on the timing procedure, it is important to gather the necessary tools and materials. These include a timing light, a dial indicator, a socket wrench set, a torque wrench, and a new camshaft timing belt. Additionally, it is recommended to have a helper assist you during the process to ensure accuracy and safety. With the proper preparation and careful execution, timing a D16 cam is a manageable task that can significantly enhance the performance and reliability of your engine.

Locating Timing Marks

Before you can begin timing a D16 cam, you need to locate the timing marks on the camshaft and the cylinder head.

Camshaft Timing Mark: The camshaft timing mark is typically a small notch or dot on the end of the camshaft. It is used to align the camshaft with the crankshaft.
Cylinder Head Timing Mark: The cylinder head timing mark is usually a small arrow or triangle on the top of the cylinder head. It is used to align the cylinder head with the camshaft.
Crankshaft Timing Mark: The crankshaft timing mark is a small notch or dot on the crankshaft pulley. It is used to align the crankshaft with the camshaft and cylinder head.

Once you have located all of the timing marks, you can begin the process of timing the camshaft.

Setting the Crankshaft

To accurately time a D16 camshaft, it’s crucial to begin by setting the crankshaft at Top Dead Center (TDC) of the compression stroke. This ensures that the piston is at its highest point in the cylinder and the valves are in the correct position for camshaft installation.

Locating TDC

1. Remove the distributor cap and rotor.
2. Locate the timing mark on the crankshaft pulley, which is usually a notch or a line.
3. Rotate the crankshaft slowly clockwise until the timing mark aligns with the TDC mark on the engine block or timing scale.

Setting the Piston at TDC

4. Insert a piston stop or long screwdriver into the spark plug hole of the first cylinder.
5. Turn the crankshaft slightly clockwise and counterclockwise until the piston stop makes contact with the piston at the top of the cylinder.
6. Once the piston is at TDC, the crankshaft timing mark should again align with the TDC mark.

Additional Tips

– Ensure that the crankshaft is not at TDC of the exhaust stroke. In this position, the piston will be slightly below the top of the cylinder, and the timing mark will also align.

– If the timing mark is not visible, you may need to remove the crankshaft pulley or timing chain cover for better access.

– Double-check the TDC position by rotating the crankshaft two full revolutions and confirming that the timing mark aligns with TDC each time.

Aligning the Cam Timing

1. Set the Engine to Top Dead Center (TDC)

Locate the TDC mark on the crankshaft pulley or flywheel.
Rotate the crankshaft clockwise until the mark aligns with the pointer on the engine block.

2. Install the Cam Gear

Place the cam gear onto the camshaft.
Align the timing mark on the cam gear with the mark on the camshaft.
Tighten the cam gear bolt to the specified torque.

3. Install the Cam Chain

Route the cam chain around the cam gear and crankshaft sprocket.
Ensure that the chain is tensioned properly by using a cam chain tensioner or sprocket.

4. Adjust the Cam Timing

Loosen the cam gear bolts slightly.
Rotate the cam gear to align the timing marks on the cam gear and camshaft.
Tighten the cam gear bolts to the specified torque.

5. Install the Timing Cover

Place the timing cover over the cam gears and chain.
Install the timing cover bolts and tighten them to the specified torque.
Double-check that the timing marks are still aligned.

Checking the Timing Marks

Once the timing cover is installed, ensure that the timing marks are still aligned by:
- Using a dial indicator to measure the lift of the valves at TDC.
- Inserting a feeler gauge between the valve and the rocker arm.
- Observing the position of the piston at TDC through the spark plug hole.

Method	Result
Dial indicator	Valve lift should be at the specified value for TDC.
Feeler gauge	Feeler gauge should fit between the valve and rocker arm with no or minimal clearance.
Spark plug hole	Piston should be at the top of its stroke.

Tightening the Cam Bolts

Tightening the cam bolts is a crucial step in timing the D16 cam correctly. A torque wrench is required for this step. Here are the detailed instructions:

1. Insert Cam Bolts

Insert the four cam bolts into their corresponding holes on the cam gear. Ensure they are oriented correctly.

2. Apply Thread Locker

Apply a small amount of thread locker to the threads of the cam bolts. This will help prevent them from loosening due to vibration.

3. Tighten Bolts to Specified Torque

Using a torque wrench, tighten the cam bolts to the specified torque. The torque value for the D16 cam bolts is typically 65-72 ft-lb (88-98 Nm). Refer to the table below for cam bolt torque specifications:

Cam Bolt Size	Torque
10 x 1.25 mm	65-72 ft-lb (88-98 Nm)

4. Retighten Bolts After 500 Miles

Once the engine has been running for approximately 500 miles, recheck the torque on the cam bolts. This is to ensure they have not loosened over time.

Rechecking the Timing

With the timing set, crank the engine over by hand several times to make sure the valves are not hitting the pistons. To do this, remove the spark plugs and insert a long screwdriver or other suitable tool into each cylinder. As you crank the engine, watch the tool; if it moves, the valve is hitting the piston. If this happens, readjust the timing until the valves clear the pistons.

Once you are satisfied that the timing is correct, start the engine and let it idle for a few minutes. Check for any unusual noises or vibrations. If there are any problems, stop the engine and recheck the timing.

Valve Clearance

When you are timing the cam, it is also a good time to check the valve clearance. The valve clearance is the amount of space between the valve stem and the rocker arm. If the valve clearance is too small, the valve will not open fully and the engine will not run properly. If the valve clearance is too large, the valve will make noise and may eventually burn out.

The correct valve clearance for a D16 cam is 0.004 to 0.006 inches. To check the valve clearance, you will need a feeler gauge. Insert the feeler gauge between the valve stem and the rocker arm. There should be a slight drag on the feeler gauge as you move it back and forth. If there is no drag, the valve clearance is too small. If the feeler gauge moves too easily, the valve clearance is too large.

To adjust the valve clearance, you will need to loosen the locknut on the rocker arm and turn the adjusting screw. Turning the adjusting screw clockwise will decrease the valve clearance, while turning it counterclockwise will increase the valve clearance.

Valve	Clearance
Intake	0.004 to 0.006 inches
Exhaust	0.004 to 0.006 inches

Once you have adjusted the valve clearance, tighten the locknut and recheck the clearance. Repeat this process for all of the valves.

Reassembly and Final Adjustments

Lubrication

Generously lubricate the camshaft journals, lobes, valve lifters, and pushrods with engine assembly lubricant. Coat all surfaces where there is metal-to-metal contact.

Valve Covers

Install the valve covers with new gaskets. Torque the bolts to the manufacturer’s specifications. Tighten them evenly in a crisscross pattern to prevent warpage.

Intake and Exhaust Manifolds

Align the intake and exhaust manifolds with the cylinder heads. Install new gaskets and tighten the bolts to the manufacturer’s specifications.

Timing Cover

Clean the mating surfaces of the timing cover and engine block. Apply a thin layer of silicone sealant to the gasket and install the timing cover. Tighten the bolts to the manufacturer’s specifications.

Gasket Removal Tool

Use a gasket removal tool to carefully scrape off any excess silicone sealant from the mating surfaces.

Distributor

Install the distributor with a new O-ring. Rotate the engine until the timing mark on the distributor shaft is aligned with the mark on the engine block.

Ignition Timing

Adjust the ignition timing to the manufacturer’s specifications using a timing light. Connect the timing light to the engine and ground, and align the light’s timing mark with the timing mark on the crankshaft pulley. Start the engine and adjust the distributor until the timing mark on the crankshaft pulley aligns with the specified mark on the timing scale.

Final Adjustments

After running the engine for a short period, recheck the torque on all bolts and connections. Inspect for any leaks or unusual noises. Adjust the valve clearances, if necessary, as per the manufacturer’s specifications.

Post-Timing Verification

Once the camshaft has been installed, it’s crucial to verify the timing. This process ensures that the camshaft is correctly synchronized with the crankshaft. Here are the steps to perform post-timing verification:

1. Remove the Distributor Cap

Locate the distributor cap and carefully remove it to expose the rotor and distributor contacts.

2. Find the Timing Mark

Identify the timing mark on the crankshaft pulley or flywheel. It’s generally a notch or raised line.

3. Align the Timing Mark

Crank the engine manually using a wrench or breaker bar until the timing mark is aligned with the reference point on the engine.

4. Check Rotor Position

With the timing mark aligned, inspect the position of the rotor. It should be pointing directly at the contact for the cylinder that’s at top dead center (TDC) on the compression stroke.

5. Verify Firing Order

Follow the distributor cap wiring to ensure that the firing order is correct. The spark plug wires should connect to the contacts in the firing order sequence, as per the engine manufacturer’s specifications.

6. Check Ignition Timing

Using a timing light, connect it to the cylinder that’s at TDC and aim it at the timing mark. Turn on the engine and adjust the distributor until the timing light flashes at the correct advance setting specified for your engine.

7. Reinstall Distributor Cap

After confirming the timing, reinstall the distributor cap and tighten it securely.

8. Double-Check

Crank the engine manually again to double-check the timing. Ensure that the timing mark is still aligned and the rotor is pointing at the correct contact.

9. Advanced Timing Inspection

For engines with variable valve timing (VVT) systems, it’s essential to verify the advanced timing settings. This requires advanced diagnostic equipment, such as a scan tool. Refer to the vehicle manufacturer’s service manual for specific instructions on VVT timing inspection.

Ignition Timing Setting	Description
0° BTDC	Default setting for most engines
5-10° BTDC	Performance engines with higher compression ratios
15° BTDC or more	Racing or modified engines

1. Finding TDC

Before you can time your D16 cam, you need to find TDC (top dead center). This is the point at which the piston is at the highest point in its travel. TDC is measured in degrees before or after top dead center (BTDC or ATDC). To find TDC, you will need to remove the spark plugs and insert a dial indicator into the spark plug hole.

2. Setting the Timing Belt

Once you have found TDC, you can set the timing belt. The timing belt is a belt that connects the crankshaft to the camshaft.

3. Adjusting the Cam Phaser

The cam phaser is a device that adjusts the timing of the camshaft. The cam phaser is controlled by the engine’s computer.

Troubleshooting Common Timing Issues

1. The engine is running rough

If the engine is running rough, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly.

2. The engine is not starting

If the engine is not starting, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly.

3. The engine is overheating

If the engine is overheating, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly.

4. The engine is knocking

If the engine is knocking, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly.

5. The engine is idling too high or too low

If the engine is idling too high or too low, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly.

6. The engine is backfiring

If the engine is backfiring, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly.

7. The engine is losing power

If the engine is losing power, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly.

8. The engine is running on only one cylinder

If the engine is running on only one cylinder, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly.

9. The engine is making a strange noise

If the engine is making a strange noise, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly.

10. The engine is consuming too much fuel

If the engine is consuming too much fuel, it could be a sign that the timing is off. Check the timing belt and cam phaser to make sure they are set correctly. The timing is also important for fuel economy. The fuel consumption is different depend on degree of camshaft timing.

Degree of timing	Fuel consumption (mpg)
0 degree	25
5 degree	24
10 degree	23
15 degree	22

When the degree of camshaft timing bigger, the fuel consumption is bigger.

How to Time a D16 Cam

Timing a D16 cam is an important step in ensuring that your engine is running properly. The camshaft is responsible for opening and closing the valves in the engine, and if it is not timed correctly, the engine will not run smoothly or efficiently. There are a few different ways to time a D16 cam, but the most common method is to use a timing belt.

To time a D16 cam using a timing belt, you will need the following tools:

A timing belt
A camshaft sprocket
A crankshaft sprocket
A timing belt tensioner
A wrench
A socket set
A torque wrench

Once you have gathered your tools, you can begin the process of timing the cam. First, remove the old timing belt from the engine. Then, install the new timing belt on the crankshaft sprocket, and then on the camshaft sprocket. Make sure that the timing marks on the belt are aligned with the timing marks on the sprockets.

Next, install the timing belt tensioner. The tensioner will help to keep the timing belt tight, and it is important to make sure that it is installed correctly. Once the tensioner is installed, you can torque the bolts that hold the sprockets in place.

Finally, check the timing of the cam. To do this, use a timing light to shine a light on the timing marks on the crankshaft and camshaft sprockets. The timing marks should be aligned with each other. If they are not, you will need to adjust the timing of the cam.