Snapped exhaust mani stud...

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Ziggy
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Post Sat Apr 15, 2006 8:14 pm

Well taking my exhaust manifold off went quite well, didn't break any studs, but I did discover that one of them was already broken :cry:

It's (of course) the one closest to the bulkhead (bottom left), and has broken off about 1mm inside the head.

So what's best to do about it? I could try and get a drill / easyout on it but I think I'll struggle due to where it is...
What'll happen if the mani's just held on with 11 studs? Didn't seem to be a problem before (that wasn't the reason for taking it off!)...

Cheers :thumb:
E30 in need of wiring loom smoke since April '11...
wildeian
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Post Sat Apr 15, 2006 8:25 pm

I had the same problem, but it was the top right stud so bit easier. Got a right angled drill bit and easy-out in there - f*ckin' easy-out twisted and bent on me!!! I was gonna take the head off to drill it out, then along came another engine, so I took the lot out!!

Being in such an difficult place I would say you're gonna be hard pushed to do it in situ.

I knew about my stud snapping and ran it for about a year with a little bit of exhaust paste, and no apparent problems.

Good luck!
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Brianmoooore
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Post Sat Apr 15, 2006 9:29 pm

You'll never do it in situ. Hard enough with the engine out, and easyouts NEVER work.
If the broken end can't be welded to. I drill the stud slightly off centre, starting with a small drill, then working up untill I reach a size where the drill just breaks into the threads at one point. Then, with the help of a small pointed chisel, you can collapse the remains inwards slightly and then tease them anticlockwise to extract them.
This gives a bit of damage to the head on one side of the hole, but causes no problems in practice.
jmc330i
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Post Tue Apr 25, 2006 12:17 pm

I had the top right stud snap on my M20 when the engine was in the car - I ran it for about a year with 11 studs and didnt have any probs - it didnt even blow.

Ive now got 3 snapped manifold studs (long story) on my M20 so Im going to be getting them out soon. All 3 are flush or just below the level of the head :cry:
The one thing on my side is that the engine is on my garage floor.

When you say 'easyouts', is that those things where you drill a hole into the stud and then hammer the 'easyout' into the stud?

Ive also heard of the left hand drill bit method. Anybody tried it??
James
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'93 318i touring 16v
boomer
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Post Tue Apr 25, 2006 12:25 pm

Ziggy wrote:Well taking my exhaust manifold off went quite well, didn't break any studs, but I did discover that one of them was already broken :cry:

It's (of course) the one closest to the bulkhead (bottom left), and has broken off about 1mm inside the head.

So what's best to do about it? I could try and get a drill / easyout on it but I think I'll struggle due to where it is...
What'll happen if the mani's just held on with 11 studs? Didn't seem to be a problem before (that wasn't the reason for taking it off!)...

Cheers :thumb:
Dr. Holts fabulous Gun Gum is the answer - a squeeze either side of the gasket before replacing manifold, torque remaining bolts correctly, leave overnight and voila.......no blow.

Well it's worked for me - 2 snapped, bottom left nearest bulkhead and top right nearest rad.