Introduction

This guide provides a detailed walkthrough on how to time an BMW N52 engine, including reassembling the Vanos system, based on a comprehensive video tutorial. Follow these steps carefully to ensure accurate timing and engine performance. ***Disclaimer: The following instructions should be used as an educational guide since the specific steps may differ from vehicle to vehicle. Please be extra careful when timing an engine because if you get it wrong, the result can be catastrophic.***

What Tools Do You Need?

You will need a N52 Timing Tool Kit in order to lock the camshafts in place and can purchase a good quality one on Amazon or Ebay. Please be careful when buying the cheap tools, they are cheap for a reason and normally dont fit properly. I have had good results with the following N52 Timing Gear Set. Note: As an Amazon Associate I earn from qualifying purchases and I would greatly appreciate if you could use the following links to tools and other gear as it helps me fund this blog and my youtube channel.

DPTOOL Master Engine Timing Vanos Cam Camshaft Locking Tool Compatible for BMW 2.5 3.0 N51 N52 N53 N54 N55 S55

• Compatible Vehicles : Applicable to BMW N51;N52 ;N53; N54; N55; S55 Engiens
• Package: 1x Camshaft Crankshaft Timing Locking Tool Kit, 1x blow molding case

Buy on Amazon

Step-by-Step Instructions

1. Finding Top Dead Center (TDC)
   
   • Rotate the crankshaft using a long tool (screwdriver or magnet pickup), observing the piston’s movement [00:43].
   • Confirm the engine is at TDC when the QR codes on top of the camshafts are visible and facing upwards [01:29]
2. Locking Components at TDC
   
   • Cams: Use a specialized tool to lock the camshafts in place once TDC is found [01:50].
   • Flywheel/Flex Plate:
     • Normally, a tool is pushed into the flex plate to lock it [02:00].
     • Set up the flywheel so a small pin can be inserted to lock it at TDC [03:30].
     • If the pin doesn’t fit, clean the hole and use WD-40. Rotate the flywheel slowly until the hole aligns [05:57].
3. Installing Timing Components
   
   • Camshafts: Ensure the QR codes on the camshafts face up when the engine is at TDC [02:20].
   • Vanos Units:
     • Identify the “in” (intake) and “aus” or “ous” (exhaust) markings on the Vanos units [08:10].
     • Install the intake Vanos unit on the intake side and the exhaust unit on the exhaust side [08:25].
     • Ensure the timing chain is properly seated in its guide before placing the Vanos units [08:49].
     • Address any issues with the timing chain being too tight or tangled to ensure proper slack [10:02].
4. Setting the Timing and Tensioning
   
   • Vanos Timing Tool: Use a specific tool to set the Vanos timing once the engine is locked at TDC and the cams are locked [12:44]. Fit the tool’s tabs into the corresponding holes on the Vanos units [13:08].
   • Chain Tensioner: Insert the tensioner tool to apply tension to the chain [13:21]. Tighten it until snug, without a specific torque spec [14:05].
5. Torquing Vanos Bolts
   
   • Torque the Vanos bolts in two stages:
     • Initially to 20 foot-pounds [15:03].
     • Then, add an additional 180-degree turn using a breaker bar [15:46].
6. Final Checks
   
   • After timing, remove the flywheel lock and place the engine back on the stand [17:06].
   • Reinstall the original chain tensioner [19:26].
   • Note any unusual sounds, such as clicking, and investigate if necessary [18:56].

Conclusion:

With the engine now timed, it’s ready for the next steps in the engine swap process [17:06]. Remember to consult the video and a professional mechanic if you encounter any difficulties or are unsure about any steps.