Recheck basic engine timing with BMW special tools rather than timing marks alone. Lock the crankshaft at TDC with tool 11 2 300 and align the camshafts with tool 11 3 240 so the cylinder 1 cam peaks face each other and the sprocket arrows point up. If cam correction would move valves on cylinders 1 and 4, first turn the crank about 90 degrees from TDC in the direction of rotation to avoid valve-to-piston contact. Install and unlock the chain tensioner, press it against the chain, recheck cam adjustment, and remove the locking tools before cranking or running the engine.
The owner of a 1992 BMW 318i coupe replaced the timing chain and guide, then found the engine cranks but will not start. The expert explained that BMW timing must be set by locking the crankshaft and camshafts with special tools, not by marks alone, and outlined the alignment procedure with warnings about possible cam or valve damage if timing is incorrect.
