Weird S54 Rattle/Tick Noise

[Sid_E46]

My friend recently purchased an E46 M3 which has a strange ticking/rattle noise emanating from the motor. It's no secret that the S54 is a noisy motor but is this sound anything to worry about or is it just normal. The car recently had the rod bearings replaced, valve shims checked, and Beisan chain guide and oil pump disk installed.

https://www.youtube.com/watch?v=XsfZeA0B0lI&ab_channel=ReflexGS

[heinzboehmer]

The higher frequency "click" sounds like a good ol S54 to me. As you said, these engines are noisy.

The lower frequency "thump" is not normal. Maybe a heat shield or plastic piece rattling somewhere? Hard to tell with a short video clip.

[Xmetal]

Sheared VANOS bolts? I don't know - sounds a lot like this car => https://www.zpost.com/forums/showthread.php?t=1808145

[lemoose]

sounds just like what xmetal posted. relatively 'lucky'

[/M3]

Sheared VANOS bolts? I don't know - sounds a lot like this car => https://www.zpost.com/forums/showthread.php?t=1808145

Wow, sounds exactly like my car in the first post, but mine is not as loud.

So far done within the last 8,000 miles:

- BMW's updated VANOS cam bolts (4 out of 6 bolts were split in half)
- Beisan VANOS oil pump disk (had some wear)
- Beisan entire sealing kit
- Beisan timing chain guide (was split in half)
- Rod bearings (lots of copper)
- Valve adjustment (90% of the valves were out of spec)
- Engine mounts
- Guibo/flex disc
- Center driver shaft support
- Every drop of fluid replaced

The car sits at 108,000 miles and pulls very healthy and once the oil reaches to the operating temperature the sound goes away. But I know that this is not one of those usual S54 symphonies. It just doesn't sound right.

[Sid_E46]

Sheared VANOS bolts? I don't know - sounds a lot like this car => https://www.zpost.com/forums/showthread.php?t=1808145

This car did have quite a few sheared cam bolts but they have all been replaced with updated hardware.

[Arith2]

Could be an oiling issue because of the oil disk. There was a thread on using another oil disk from a different Vanos. The pistons in the oil disk could sticking. That was another mention in the thread. Was the vanos filter replaced?

[/M3]

Just wanted to give an update in case anyone comes across a rare occurrence as this one.

As noted above, the VANOS was rebuilt with the genuine BMW updated cam bolts, Beisan oil pump disk, viton rings etc. We went in again, this time to install the 272/280 cams that I bought on betr a while ago and realized the intake side cam bolts that we had just replaced 12K miles ago have failed again. So with all the honesty, we would have never thought of inspecting the cam bolts if it wasn’t for the cam upgrade. Not sure if this was an install error on our end or something got damaged when the original 4 out of 6 intake side cam bolts failed. But this time we installed Lang Racing cam bolts with super care.

Either way, the rattle is gone and the motor sounds super happy. Will be on the dyno for a live tune in hopefully a few weeks.

[jet_dogg]

By failed you mean sheared?

Thanks for providing an update for future users to reference even though you weren't the original poster.

[/M3]

Sheared, correct. I am not the OP, but the original post was about my car.

[sapote]

and realized the intake side cam bolts that we had just replaced 12K miles ago have failed again..

Weird. What torque these bolts were tighten to, and if Loctite was used on the cleaned cam threaded holes?

[/M3]

Weird. What torque these bolts were tighten to, and if Loctite was used on the cleaned cam threaded holes?

To factory torque specs with Loctite. We may have not cleaned the oil in the cam holes good enough, which could have cancelled out the Loctite. Really not sure. But my friend who helped me done this quite a few times. This whole thing is still a mystery to us.

[sapote]

I cleaned the threaded holes really good, then again with alcohol with Qtip before install the bolts