Sheared water flange bolt removal

The 3 bolts holding the leaking water flange to the front of my KR block had corroded or rounded off to the point where Allen keys just spun.

I bought an Irwin Bolt remover kit and as you might guess, they sheared, even after plus gas (2nd bolt).

3rd one is still in but I need to remove the inlet manifold to get a better grip with the irwin.

Question 1 for now is: would you dremmel a slot in and turn it out, or punch/drill the centre then use an extractor tool?

I have a dremmel but no extractor.

Cheers

Pic:

 

I think your best option is to try drilling into it and then using a screw type extractor as you suggest. I've had those exact bolts snap on me too, and I admit I gratefully left them to the machine shop to sort - though I was fortunate in that the head was off for work anyway. My personal experience with using extractors myself has always been an abysmal failure. But that's possibly because I've used cheap ones (e.g. Draper) or haven't drilled and wound them in far enough, leading them to snap - giving a bigger problem.

 

Eish! Left yourself with a right job now!

I think I read somewhere on here about removing sheared bolts, like yours have done. Could well be a MUSHY tip!

I know the idea of removing corroded bolts with heat would be the go to method if all else fails. Problem here is you have an oxidized section of a mild steel bolt. The best section of it is in the casting. The idea is to heat the area of the casting where the threads are & not the bolt itself.

If you have access to a mig welder, this might work. Take a washer (presume 6mm), pop it over the stud and tack it proper. Then take a nut, hold it on the washer & weld nut to washer through middle of nut. Sufficient heat would have been transferred to the area required and you also have a hex head to use a spanner on. Same for the stud that has a bit sticking out. For the bolt still in tact, find a torx bit you can drift into the what was a hex, an adaptor and a wobble extension. First heat the area below the leftover sandwiched flange, nice and easy! Have the torx bit in the adaptor, ready for driving it into the hex, with a plan on how. Heat and inertia are playing the part here. Hopefully that should be enough. By the time you have the wobble extension on the adaptor, you should be able to wind it out by hand.

I'd be all for replacing those bolts with a stainless equivalent using a spring & flat washer. Grease the threads too & don't overtighten it

 

The guy who rebuilt turbos for us, for years was a real old school engineer. And obviously had to deal with a lot of seized and corroded studs, sheared off. He maintained the best method was heating the offending item up til it was red hot, then rapidly cooling it with water. Thermal shock treatment.

 

And buy yourself a set of these asap. Ball headed long hex metrics, you need to remove the intake too and be mindfull its the fuel side of the block!

 

Thanks for the replies. I have been thinking of buying a MIG welder for ares of rust, this is another reason to get one, but might be too tough of a first job for me. This route sounds like a good idea though otherwise.

I'm also worried about heat as I'm a novice at 'proper' mechanics. I'll Google the best way and safety procedures.

I also tend to go for cheap tools, so thanks for pointing out that now is the time to not do that.

Gonna think this through for a while. Determined to at least try one option myself. I bought the car to learn these things.

 

I'd weld a nut to the end. Not only does it give you something to grip, it heats the thread enough to crack it loose

 

Is welding a nut on something a novice (with a bit of practice on spare bolts first) could do?
I have never touched one before.

And would I need to shield the fuel lines and injectors?

 

Only if you practice first. !!!

IMO, if you try stud extractors etc, you`ll most likely end up breaking those too. It takes a lot to shear the top off an M6 cap head. That stud will be TIGHT in the hole.

You need a LOT of heat on the stud before even attempting a stud-extractor IME.

 

Seems like the majority agree on heat. Think I'll SORN the golf and buy a welder and practice (want to learn anyway).
I'm tempted to still try cutting a groove in and try turning, but might be less stud to weld to when that doesn't work.

Thanks again for help

 

Holy shizzle, what a nightmare!

I tried the welding a nut on technique. Admittedly it is the first time I have ever welded, but each time the stud just twisted and gave in. I then tried the slot technique, not a chance, like cheese. I then drilled a hole in them but didn't want to drill all the way incase it ruined the head, so bought stud extractors, which was a big mistake.

Many people warned against them but I thought I'd try it and not put too much force on it. Well, it snapped first time with hardly any force. It took days (couple of hours each evening I mean) to drill around it, dremel through it, but finally got the bugger out.

However, I am left with a whopping big hole. See pic.

What is the next step? Weld it up and drill again? Can a novice do that?

The first 2 need helicoils, could I fit a longer stud and helicoil the lower half of the hole which is the same size as the first 2 at 6mm? (I believe to helicoil I need to drill a 6.3mm hole then tap it.

Need to do this to feel some sense of achievement! Help!

 

Feel better already!
I tried an 8mm stud but there is a metal sleeve in the hole of the plastic flange. I did wonder if it was possible to knock the sleeve out, drill it bigger then bend the sleeve out to size. There would be sturdy plastic 70% around it and a thin bit 30%. Pic attached:

 

Thanks for your help
I think the hole is too big. An M8 bolt goes in 7mm before catching any metal, and there is 1mm or so space around it at the surface. I did see these keenserts, looks like I could use an m6 inside and m10 outside thread one. This sounds ideal. Have you any experience with these?

http://uk.rs-online.com/web/p/thread-repair-inserts/6684667/

I at least got a VW plastic flange not an eBay plastic one lol.

 

http://www.ebay.co.uk/itm/Thread-Ad...hash=item2ee1770068:m:mBWd1kqjGKtseUB-YlQ3QGw

could you use those to have a bigger thread in head and use the std part with nuts ?