Removing a rounded bolt in a threaded hole

timmygobang

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www.todayiboughtaboat.eu
Long story cut short I have a bolt I bold thats rounded. I was going to take a dremel and lop the top off and hammer it through, but turns out the bracket is threaded and even pliers wont turn the bolt. Is there any special tool or technique I can use to get the ruddy thing off?

Typically its in a very confined space thats hard to get to. Shall i just destroy the bracket? it connects the exhaust outlet to the webasto heating box.

The exhaust pipe came loose on a trip about a month ago, its one of those jobs awkward jobs I keep putting off :(
 
(quick google on surface drive sockets)

This is a better type of socket to prevent rounding bolts in the future?
A decent surface drive socket will remove even a badly rounded bold quite easily. I seem to have a particular problem with 10mm bolt heads, so I use a surface drive socket as a matter of course these days. Halfords sell them individually.
 
I have a stud extractor on board if you are currently anywhere near Shoreham...
The sort with a gert great lump of steel and an eccentric knurled wheel to which one connects an even bigger spanner.

Rather like this: http://www.lawson-his.co.uk/gedore-8010700-stud-extractor-128-2-p71292

You will need at least 3/8" of stud accessible. It's effective enough to snap a half inch dia. stud if it will not budge.

Stillson wrenches are also designed for the job. Furthermore if sized appropriately they actually work.


Also PlusGas it a.s.a.p. and if it will still not move, heat it.
 
Select a slightly smaller socket and hammer it on. Get a good spanner monkey to try to remove bolt. He will be able to detect the onset of yield or breakage and stop before twisting off the head. If not to be found have a go yourself.

Apply heat and PB buster and try again.

NB I used Snap On sockets for jobs like this because they had a no quibble lifetime warranty.
 
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If I read you right this is just the exhaust clamp, they can be a pain, bolt and captive nut on the other side, do not hit with hammer as the alloy exhaust stub it connects to can fracture meaning a new heat exchanger. Cheap and easily available part so if destroying it is the easiest way then go ahead, replace with stainless marine clamp & bolt to avoid recurrence.
 
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I've got a set of these Super Wrench, 4 different sizes to a set & these have removed rounded bolts for me in the past. The harder you pull the more they grip.

View attachment 38197
I have a set also. Seemed most impressive from the guys demonstrating at LIBS a few years ago and I found easy to use. Not yet used in anger against rounded bolts / nuts.
 
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