Broken Exhaust Header Bolts

I have two sheared-off exhaust header bolts. I expect that they will have to be drilled out and re-tapped or helicoiled. This isn't something I'd be prepared to attempt myself, so I'm looking for recommendations for experts in this field.

9Excellence can do it and I guess most other Indies too.

Did the rest of the exhaust manifold bolts come out? If so you did well! A special jig and patience is required, as mentioned above most indies should have sure a tool, be very wary of anyone who says they can drill it out by hand!

Should you want to know what the task involves, it might be worth beaming up this vid which may give you an idea if indeed it is a task you could take on or not...? https://youtu.be/SXTSIsi4IJ4

Broken exhaust header bolt Brilliant video. Mine will need doing at some stage, but I think all the bolts will shear. If they do all shear can the Stromski kit still be used as there will be no tapped holes to secure it to the cylinder head?

Where are you based? Ben from String Theory Garage in Warwick has all the jigs and the minerals to undertake such a job. He also has some excellent replacement studs in titanium, I would strongly recommend using such a kit prevent any future issues with galvanic corrosion. I used one of his stud kits with copper flange nuts and a liberal coating of Permatex anti-seize coating.

I think there's a forum member, TheFinn maybe?, who rents the jig out. My headers are going to need replacing soon so I've bought some titanium studs in readiness. Good luck

The stomski jig has two threaded sleeve nuts so providing you have a couple of the snapped studs protruding with useable thread you should get it on. My thinking is that if the first 4 snap I'll power file the heads of the last two to maximise useable threads!

Details on using the Stomski jig here. I do lend it out, but it isout at the moment. MC

broken exhaust header bolts. OK, I did not realise that, removing what is left of the bolt head should not be too much of a problem, which hopefully will leave some usable thread protruding from the cylinder head. Many thanks.

Titanium and Ally knit together as they're at opposite ends of the Galvanic scale. My mate works in Aerospace and claims its a big no-no. My 7 year old stainless bolts wound straight out the other week no problem.

:wave: I have one if you need it let me know. One of the comments says the Stomski jig has sleeved nuts to screw the jig onto but the Stomski kit doesn't have these only guides that have a slight recess so if there is some old bolt sticking out you can still get the guide on without grinding flush. That said a very kind forum member who had my jig did have the problem where all bolts snapped and he did make some sleeves / guides that you can screw onto any thread left to hold the jig in place, which I now send out as part of my kit.

The kit already has them - you unscrew the gold part off the fixing bolts and it is threaded inside.....

Hmmm now I'm confused (not hard to do I guess) but I "assumed" titanium was the "go to" for non seizing materials for exhaust studs based almost entirely on this thread? http://911uk.com/viewtopic.php?t=110603&start=0&postdays=0&postorder=asc&highlight=studs I could easily be wrong as I have no experience in this area.

In a bid to reduce your confusion, I too have stainless bolts through mild steel exh manifold flanges that have been on my V8 alloy engine for at least twenty years that I know of, and which had not been touched in that time other than the last time this question arose on this forum not so long ago, and as the result I took a spanner to a couple... and they came loose without issue.. Having typed that I liked the look of the pic posted with SS studs and copper (?) nuts, interesting. I have memories of a time when standard exh manifold fixings were long brass nuts on generally corroded steel studs.. I would be happy to swap the fixings on my 2012 991`s manifolds, if I thought they would come out without issue and replace them with SS studs and nuts in the hope that the threads in the heads would never need to be disturbed at any future time, in that nuts could be removed by one means or another if required. The main issue being how likely is it that the manifold fixings on my 2012 40k mile 991 might shear too, given a pal sheared quite a few on his 26k mile 997... requiring him to involve the Stormsky processes, but then he was fitting a new stainless exh system just to tidy things up.. Me.. ? I would just be seeking to tidy things up a bit as an investment in preventative maintenance and self satisfaction... Perhaps another example of Nuts or what.. :?: :grin: