Essential Car Engine Cam Timing Locking Tool Set for N55 Engines

Timing your N55 engine’s camshafts can be a daunting task. This comprehensive guide, along with the right Car Engine Cam Timing Locking Tool Set, will provide the steps and insights needed for a successful timing job. This process requires precision and attention to detail, so having the correct tools is paramount. A quality locking tool set ensures accurate camshaft alignment and prevents costly engine damage.

Understanding N55 Cam Timing Basics

Before diving into the procedure, let’s clarify some critical points regarding N55 camshaft sprockets:

• Sprocket Identification: Intake VANOS sprockets are marked with “EIN” and exhaust sprockets with “AUS.” These are not interchangeable.

• Timing Disc Interchangeability: While intake and exhaust sprockets are unique, their timing discs are interchangeable.

• Avoid Generic Tool Sets: Cheap, universal car engine cam timing locking tool sets often advertised for multiple BMW engines are not recommended. N55 sprockets have specific operating angles (50-70 degrees crank angle for intake, 45-55 degrees for exhaust) that differ from other N-series engines. Using incorrect sprockets can negatively impact ECU performance and engine efficiency. Always opt for a tool set specifically designed for the N55.

  (Alt: An N55 engine with the camshaft timing tools and chain installed)

Essential Tools and Preparation

• Car Engine Cam Timing Locking Tool Set: This specialized kit ensures accurate camshaft alignment.
• Torque Wrench: Precise torque application is critical for TTY bolts.
• New Sprocket Bolts: These are Torque-To-Yield (TTY) bolts and must be replaced. Reusing old bolts can lead to insufficient clamping force and potential timing chain failure. TTY bolts stretch within a specific range to provide optimal clamping force. Once removed, they lose this property and cannot be reliably reused.
• TDC Locking Pin: This tool locates and secures the crankshaft at Top Dead Center (TDC).
• Dummy Timing Chain Tensioner: This tool maintains chain tension during the timing process.
• Spark Plug Socket and Wrench: Removing spark plugs eases crankshaft rotation.
• Optional: Long Zip-Tie or 1/4″ Drive Extension: Helps visually confirm TDC on piston #1.

(Alt: Close up view of the camshaft alignment tool inserted into the camshaft)

Step-by-Step N55 Cam Timing Procedure

1. Pre-Positioning: Roughly align the crankshaft and camshafts to their TDC positions without using locking tools. Ensure intake and exhaust camshaft Upper Position Covers (UPCs) are facing upward. The timing chain should be off at this stage. While carefully rotating the exhaust camshaft is generally safe, it’s best practice to pre-position the crankshaft near TDC to minimize risk.

2. Camshaft Locking: Install the car engine cam timing locking tool set onto the camshafts first. Ensure a snug fit and square alignment of the tool before fully tightening the allen bolts. This establishes a fixed reference point for subsequent steps.

3. Sprocket and Chain Installation: Mount the VANOS sprockets with the timing chain onto the camshafts. Hand-tighten the sprocket bolts, ensuring the timing discs are in place. Use oil if needed to facilitate installation. Aligning a notch mark on the sprocket teeth with the UPC position can provide additional accuracy, although not explicitly mandated.

(Alt: The timing chain installed on the sprockets with the engine at TDC)

4. Crankshaft TDC Alignment: With the sprockets and chain loosely in place, insert the TDC locking pin into the flywheel/flex plate. Ensure you are using the correct hole. There might be slight play; positioning the crankshaft on the backward side of this play biases towards the “advance” side of TDC.

5. Timing Disc Locking: Secure the timing discs to the sprockets using their dowel pins and bolts. Ensure a flush and square fit.

6. Dummy Tensioner Installation: Install the dummy timing chain tensioner and torque to 1-2 Nm. This ensures proper chain tension for accurate timing.

7. Verification: Torque the camshaft sprocket bolts to 20 Nm. With the dummy tensioner in place, remove all timing tools and the TDC pin. Rotate the crankshaft several times by hand, returning to TDC each time to verify that all tools re-engage freely. Repeat this verification process at least three times.

8. Final Torque: With the camshaft and disc locking tools in place, apply the 180-degree TTY turn to both VANOS sprocket bolts. Use a long breaker bar for smooth and controlled torque application. Minimize the number of attempts to reach the 180-degree mark to preserve the bolt’s TTY characteristics.

9. Tensioner Replacement: Remove the dummy tensioner and install the new tensioner.

10. Completion: Remove all remaining timing tools and reassemble the engine components.

Conclusion

Successfully timing your N55 engine requires a methodical approach and the correct car engine cam timing locking tool set. By following these steps and paying close attention to detail, you can ensure accurate camshaft timing and optimal engine performance. Remember to consult your vehicle’s specific repair manual for detailed torque specifications and procedures.