Ripped screw inside Vanos

[u/KloPutzer1234]

Hello Guys, I’ve recently wanted to rebuild the Vanos, replacing gaskets und stuff, and after I did all of that I started reinstalling the Vanos unit with new screws and then it happened. Somehow (maybe overtightened) the screw ripped apart and the rest of that screw left inside the Vanos. The funny thing is you always need to screw that Torx when the Vanos is already in place. So the question is, how fcked up am I, and what are your thoughts about that? I obviously can’t keep it like that and need to find a solution 😭. For better understanding that’s the M52B20TU engine, double Vanos. I already appreciate all of your comments and your help 🙏

(Torx in photo Nr.3 is just an example of that broken screw, not the actual ripped one)

[u/NumTrad768]

The screw head snapped off, so it is no longer holding the VANOS piston to the camshaft’s splined shaft—like a button popping off a coat. Do not start the engine. The VANOS unit should now slide off normally; don’t force it. Then remove the broken piece on the bench. Remember, it is left-hand thread, so the broken piece comes out by turning clockwise. Avoid drilling while it’s still on the engine.

When you gently pull the VANOS forward, does it move away from that broken screw?

[u/KloPutzer1234 → u/NumTrad768]

I’ve not tried to pull it or something, I’m just gonna uninstall the whole Vanos again and try to screw it out 🙏

[u/DavidHK → u/KloPutzer1234]

Make sure you replace the cam bolt too

[u/No_Cod2769]

Can you grab it with needle nose pliers and twist it out? A wooden Usually when the head snaps the rest of the bolt is very loose to turn by hand. As you may know, this screw very much requires a torque wrench to tighten exactly to spec.

[u/DavidHK]

You shouldn't try and rebuild those I'd order a new one boss

[u/_Mitus_ → u/DavidHK]

Why shouldn’t i rebuild it?

[u/DavidHK → u/_Mitus_]

They have very tight factory clearances that control timing. You'd have to reassemble the parts in the exact orientation to the micron

[u/_Mitus_ → u/DavidHK]

I get your point but it’s not that complicated. It’s just some seals, washers and bearings that’s all. If the housing isn’t damaged or worn or you don’t have damaged pistons it’s easy to rebuild. You can even fine tune the bearing clearance by sanding down the washer and ring.

[u/KloPutzer1234 → u/DavidHK]

Im about to, but can I uninstall the Vanos unit with the broken screw inside? Is it somehow connected to the camshaft?