Threaded bar/bolt removal - cylinder head

[WorkshopChris]

Did they shear while you were disassembling or let go as part of the original failure. Removal methods depend on the cause of failure.

 

[brightspark]

Would be quicker to just flip the reverse switch.

Oh, yes, I forgot - pillar drills don't reverse because there's never a need to, can't think why I rewired mine so I could reverse it...

ohh yes and try getting that casting on your reversible pillar drill and line it up and hold for drilling thats why mine dont reverse

 

[brightspark]

Easy job with a bit of thought - floorstanding drill with a rotating and tilting table, if that's not enough put the casting on an engine stand and clamp that to the table, swung to the side and rotated to an appropriate position.

I couldn't be bothered. no ofence but theres easier ways

 

[CLD]

Good evening gents, thankyou for all your advice.
I went round to my very local engineering shop (on the next street) and they said they had an electro-arc bolt eater that will drive a square rod into the bolt and then will be able to ratchet the rod out.
I will let you know how it goes as it will be ready 11am tomorrow

 

[fixerupper]

Sounds just the thing ...how lucky you are to have local engineering shop ......jeff....

 

[dannyp]

had the broken bolt game with head bolts on a deutz motor. 21 snaped bolts. so plenty of time to experiment

my best results were found by placeing a washer over the remanis to protect the block and stick welding nuts on useing some rods fo rbolt extarcting iirc they wre stainless.
but them not trying to rag the remians out but appling a constant relativly gentel torque and then repeatedly tapping/battering the top of the nut with a hammer.

some of them i was battering for about half an hour with assistant pulling on the spanner and soem of the nuts started to resmbel rivets but eventualy all but 4 of them moved

 

[Wedg1e]

Spark erosion is 'easy'

Ah right, well as you seem to know all about it can I ask you to knock up some reference pieces we have an enquiry for? If I remember it right, 15mm OD 304L rod, 12mm long, bored out to 6mm. Easy so far?
Well now polish that 6mm bore to <0.4 micron and then spark-erode some 'defects' in to it: typically 0.5mm long, 0.1mm wide and 0.1mm deep. Some need to run axially and some circumferentially, and then others have to cross each other in random patterns (called crazy paving). Did I mention the <0.4 micron surface finish inside the bore?
And then once you've made it, kindy measure the resultant 'defects' and provide us with UKAS-traceable certification.

 

[mcostello]

Tig is better than Mig as You can loiter around with the heat for a while,Mig instantly starts depositing metal. 14 got out of 14 in a Mercury Villager van. 3 orr 4 of them took 2-3 tries apeice. Almost used up My treasure chest of useless nuts and washers.

 

[Wedg1e]

You seem to have misunderstood the 'relative' part...

If you're fully set up for spark erosion then it's a damn sight easier using that to remove a broken stud than using a different process that you don't have the tools for.

Or do you disagree?

Well I was being facetious, maybe not enough and ; you might say that laying bricks is easier if you happen to have a trowel rather than a soldering iron

 

[EddyP]

You want a set of left handed drill bits. I had a snapped head bolt in a Volvo T5 engine, used a left handed drill bit and it wound itself out whilst in the process of drilling it.

 

[CLD]

You want a set of left handed drill bits. I had a snapped head bolt in a Volvo T5 engine, used a left handed drill bit and it wound itself out whilst in the process of drilling it.

The job is done now, but thankyou very much.
The result was very clean and like nothing was ever stuck, good to know for the future