Timing E30/E36 Camshafts and Installing VANOS: A Step-by-Step Guide

Step 1: Set Engine to Top Dead Center (TDC)

• Ensure the engine is at TDC.
• Install the TDC pin into the locking position to hold the flywheel steady.
• Lock the camshafts using the camshaft locking tool for proper alignment and timing of the camshafts and VANOS.

Step 2: Inspect Exhaust Camshaft Sprocket

• Check the sprocket for wear or damage, especially on the gear teeth and inner mounting slots.

Step 3: Install the Exhaust Camshaft Sprocket

• Mount the sprocket onto the exhaust camshaft.
• Ensure the mounting holes on the camshaft flange are visible through the sprocket slots.
• Position the holes toward the left side of the slots.
• Adjust the sprocket as needed, as it may take multiple attempts to get the correct alignment.

Step 4: Replace the Lower Chain Tensioner

• Locate the lower chain tensioner on the lower right side of the engine block.
• Remove the tensioner and replace it with a tensioner tool to keep the chain tight while timing the cams.

Step 5: Install the Tensioner Tool

• Replace the spring-loaded tensioner with the tensioner tool. This tool provides the proper tension needed for accurate camshaft timing. Hand-tighten the tool for now.

Step 6: Remove the Old Chain Tensioner

• Use a socket to remove the tensioner. Be aware that it is spring-loaded and will pop out when released.

Step 7: Inspect the Tensioner Assembly

• The tensioner assembly consists of a plunger, spring, cap, and sealing ring. Remove and inspect all parts.

Step 8: Install the Chain Guide

• Install the center plastic chain guide.
• Torque the bolts to 10 Nm. Avoid over-torquing as it could break the bolts.

Step 9: Reinstall the Top Chain Tensioner

• Reinstall the top chain tensioner and tighten the bolts to 10 Nm. Replace the tensioner if your engine has more than 80,000 miles.

Step 10: Install the Camshaft Sensor Cap

• Place the camshaft sensor cap onto the intake camshaft. This cap triggers the camshaft position sensor.

Step 11: Install the Thrust Washer on the Intake Camshaft

• Install the thrust washer onto the intake camshaft using the special studs.
• Torque the studs to 20 Nm.

Step 12: Attach the Intake Sprockets and Chain

• Attach both intake sprockets and the chain.
• Ensure the exhaust sprocket’s cup faces outwards and the intake sprocket’s cup faces inwards. Both sprockets should be mounted flush.

Step 13: Install the Sprocket and Thrust Washer

• Tighten the nuts on the intake camshaft to 10 Nm. Verify that the inside sprocket rotates freely by about 20 degrees.

Step 14: Secure the Exhaust Camshaft Sprocket

• Hand-tighten the screws onto the exhaust camshaft sprocket for now.

Step 15: Prepare for VANOS Installation

• Ensure the camshafts, chain, and sprockets are installed properly before installing the VANOS unit.

Step 16: Test the VANOS Unit

• Pull out the gear plunger of the VANOS unit. It should extend smoothly and retract without resistance.

Step 17: Apply Sealant to VANOS Mounting Points

• Apply silicone sealant around the alignment pins for the front VANOS seal on both sides of the engine.

Step 18: Install the VANOS Unit

• Install a new seal onto the front of the cylinder head.
• Rotate the front sprocket/chain assembly clockwise and ensure the VANOS plunger is fully retracted before placing the VANOS unit onto the cylinder head.

Step 19: Engage the VANOS Gear

• Rotate the spline shaft on the VANOS unit until the gears engage with the sprocket.
• Rotate the sprocket/chain assembly counterclockwise while pushing the VANOS unit onto the cylinder head.

Step 20: Secure the VANOS Unit

• Reinstall the main mounting bolt and engine lift ring.
• Tighten the VANOS housing and clean off any excess sealant.

Step 21: Adjust Chain Tension

• Pull out the retaining pins and reapply tension to the chain.
• If the tensioner is sluggish, replace it.

Step 22: Tighten the Chain and Sprockets

• Tighten the tensioner tool to 1.3 Nm to remove slack from the chain.
• With the tool still in place, tighten the four nuts on the exhaust sprocket to 15 Nm.

Step 23: Replace the Tensioner Tool

• Remove the tensioner tool and install the real chain tensioner, ensuring correct alignment with the ramp inside the engine.

Step 24: Final Adjustments

• Remove the camshaft holding tool and the flywheel locking tool.

Step 25: Complete the Installation

• Connect the VANOS oil line and electrical control line.
• Reinstall the valve cover with a new seal and reinstall the ignition coils.

Your camshafts are now timed, and the VANOS unit is installed correctly!