Snapped Cam Bolt Removal

[Sid_E46]

My friend started rebuilding his VANOS today to find 4 of his 6 intake cam bolts snapped. We have no idea have to remove the remaining part of the bolt stuck in the cam without damaging the threads or having the piece falling into the engine. Does anyone know of a way to remove snapped bolts?

Thank You

[SG/IRM3]

I encountered this problem four years ago when I found five snapped cam bolts on the intake cam. I initially tried small screw extractors with limited success due in part to the relatively tight access for a drill. What the extractors did do was rough up the surface of the remaining broken bolt enough to use a variety of small picks to fairly easily work them out by slowly unscrewing them using the tip of the pick.

[eacmen]

Might be worth the time to take the front end off so you can get more room to work.

I've never had to do this myself, but I imagine you will probably want you get a reverse drill bit in there.

The pick is a good idea, but seems like it would be very tedious to do for 4 bolts.

If it was a larger fastener then I would probably be trying to hammer a slot into the end of it and use a flathead screwdriver. But I am not sure using a hammer on the cam bolts is a good idea.

If you choose to use a bolt extractor just be careful, they are hardened metal but brittle and can snap easily. If you break off a bolt extractor then it will have to go to a machine shop for removal.

If it was my car I would be using a reverse drill and hoping the drill bit backed it out. If it didn't, then I would try tapping a torx driver into the drilled hole and trying to get it out that way.


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[Arith2]

First off, you're welcome.

Second, I have some spare cams

You can take a dremel, drill a pilot hole, and stick an extractor in. They're not going to be tight if they backed out and sheared off.

[sapote]

If no Loctite were used on those bolts then it should be easy to remove the broken parts. Use an impact driver and hammer with flat screwdriver bit to turn it CW and it should move to the #1 cam lobe.

I don't think they were Loctited bc them they should not came loose and snapped off.

Lucky that this was detected on time. The noise got you guys attention?

[maupineda]

Whatever you do, make sure you protect from any debris going down into the engine, especially if you start filing or dremmeling!

[Arith2]

Whatever you do, make sure you protect from any debris going down into the engine, especially if you start filing or dremmeling!

+1

[Obioban]

It’s so little extra work that I’d pull the cam and go after it outside of the car.

[eacmen]

It’s so little extra work that I’d pull the cam and go after it outside of the car.

Special tools required for that correct?


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[Obioban]

Special tools required for that correct?


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Nope. Just a friend to hold the cam angle while you remove it.

https://m3support.net/thread/186/e46-m3-cams-diy?page=1

[Sid_E46]

Thanks for the replies everyone, I ended up using a small harbor freight pick and slowly spun out each snapped bolt. Took a while but definitely beats having to remove the whole camshaft.