rod knock, vanos, or normal ?

[Moi]

UPDATE!!!

all of the vanos cam bolts were loose and one completely sheered off , luckily doesnt look like there is any other damage

GET YOUR VANOS SERVICED FOLKS!

thanks for all your help

[eacmen]

UPDATE!!!

all of the vanos cam bolts were loose and one completely sheered off , luckily doesnt look like there is any other damage

GET YOUR VANOS SERVICED FOLKS!

thanks for all your help

Whew! Crisis averted!

[sapote]

UPDATE!!!

all of the vanos cam bolts were loose and one completely sheered off , luckily doesnt look like there is any other damage

GET YOUR VANOS SERVICED FOLKS!

thanks for all your help

So the car had no knocking noise when bought 2 weeks ago and now both cams have loosen bolts?
I always suggest people to check and add Loctite to these bolts if the car is new to them.

[eacmen]

UPDATE!!!

all of the vanos cam bolts were loose and one completely sheered off , luckily doesnt look like there is any other damage

GET YOUR VANOS SERVICED FOLKS!

thanks for all your help

If you wanted to be extra careful you should check timing to make sure one of those sheared bolts didn't make the chain jump. Could also do compression test. If you don't have history on when rod bearings were done i would budget for that as well at some point.

[sapote]

The process of changing the cam sleeve bolts must have the vanos timing reset, as the hubs must be removed.

[Moi]

So the car had no knocking noise when bought 2 weeks ago and now both cams have loosen bolts?
I always suggest people to check and add Loctite to these bolts if the car is new to them.

i dont believe it had any knocking noise, it most definitely wasnt as loud.

[Moi]

If you wanted to be extra careful you should check timing to make sure one of those sheared bolts didn't make the chain jump. Could also do compression test. If you don't have history on when rod bearings were done i would budget for that as well at some point.

the car is at a bmw specialty shop , rod bearings are being done as well

[sapote]

i dont believe it had any knocking noise, it most definitely wasnt as loud.

You did great job of researching the noise due to loose cam bolts and avoid bent valves.

[Moi]

So the car had no knocking noise when bought 2 weeks ago and now both cams have loosen bolts?
I always suggest people to check and add Loctite to these bolts if the car is new to them.

not sure loctite wouldhave helped me. the bolt broke right under the head of the bolt.

heres a video

https://www.youtube.com/watch?v=zPLBspksklQ

[heinzboehmer]

not sure loctite wouldhave helped me. the bolt broke right under the head of the bolt.

heres a video

https://www.youtube.com/watch?v=zPLBspksklQ

The theory is that the bolts back out over time and the fatigue of the sprocket hammering into them causes failure. Loctite helps avoid the initial backing out.

[SG/IRM3]

i dont believe it had any knocking noise, it most definitely wasnt as loud.

In 2017 at 47K miles I found five cam bolts on the intake cam cut completely in half and the remaining bolt cut halfway through. I had no knocking noise or loud/unusual noise of any kind. The noise that got my attention was a whirring/humming noise that was audible only stopped at idle with the windows down. I noticed it the day after a three day track event when I pulled up to a stop sign. Doubt anyone not familiar with the car would have noticed it. I really didn't think it was the cam bolts but was aware of the problem so took it apart to check and very fortunate that I did. Did the full Beisan repair myself and six years and 19K miles later car runs great. Don't assume a loud knocking or rattling noise will be associated with this failure. OP - glad you caught it in time!

[SG/IRM3]

And I used Logitech on the new bolts...

[SG/IRM3]

Loctite !

[digger]

I'm not surprised this wasn't rod knock because of the rpm thing so probably as good a result as could be expected from those kinds of sounds

[Moi]

The theory is that the bolts back out over time and the fatigue of the sprocket hammering into them causes failure. Loctite helps avoid the initial backing out.

Yes your right!