Further to my previous thread
www.honestjohn.co.uk/forum/post/index.htm?f=4&t=14...1
The clowns who fitted my engine did not put the air con unit back on properly and consequently one of the bolts has snapped off leaving the whole full of half a bolt.
I have been advised the engine will need to come out and it will have to be dirlled out.
Anyone know of any other remedies at all please?
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If the bolt has broken in the hole, with none of it protruding, then yes, it sounds like it will need to be drilled & a stud extractor used to remove it. Taking the engine out sounds a bit drastic though...
Why don't you get the 'clowns' to sort it for you if it was their fault?
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Depending on the angle you may not have room for a drill/extractor in which case I have heard of a skilled welder, welding another bolt to the broken bolt and using that to "unbolt" the remnant.
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Yes if you can\'t get a drill in then try this. Use a welding rod with a few turns of insulation tape to prevent it arking to the casting. then select a low current setting and tack the welding rod onto the retained length of bolt then unscrew the bolf. I\'ve done this a couple of times just using a car battery but beware as there is no current limit so best to use an arc welder.
Regards Peter
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Why can't it just be unscrewed using some form of grip/wrench - is lack of access the reason ?
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I can remember a work colleague having a stud removed with a spark eroder I do know how bulky or portable this was but I am sure someone on this site will be able to tell you some more about it.
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If it's snapped due to cross threading or bottoming in a blind hole, there isn't a quick fix. It takes a lot of torque to snap a high tensile bolt, and just as much to remove it. Full access, drilling and helicoiling is the answer.
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As far as I can tell it snapped off due to the fact the top bolt on the air con unit wasn't even fitted and the stress of the fan belt caused it to snap off.
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Pros and cons of ideas suggested so far.
Extractor (basically a LH threaded self tapper)
Need space to work to drill a hole in the top of the remaining part of the bolt, then use extractor with wrench to pull out. The problem here is that cheap extractors can snap off, exhasibating the problem.
Weld another smaller bolt on and undo this using appropriate socket.
My brother in law did this on a car he bought, the plonker who sold it to him had cleverly rounded off the hexogan hole in the oil sump. This technique worked for him.
Probably won't need as much room to get a welding rod in there. As suggested, use insulation tape around hole to prevent arching (Where's the Backroom Speelchucker!) onto the surround.
In addition, when you get a good weld, use plenty of WD 40 etc, give a good soaking, then use a gentle 'rocking action' to start to loosen the bolt assembly
Drill out and helicoil
Again, access required to get drill in in the first place, Helicoiling would not be difficult.
'Mill' a slot then use an impact driver (my idea)
Again access for drill but - use a much smaller bit, which may make access easier. Eg, if we're talking an M10 threaded bolt (10mm dia) then use a 3mm bit to drill a series of hols in a straight line to create a slot. Then use an impact driver to budge it - plenty of that WD again and may work with that gentle rocking motion with the flat bit. This worked for me once.
Good luck
****Signature? - Ideas on a postcard please anyone!****
****We never stop learning****
Hugo
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A parallel extractor is a better bet than an easi - out in most circumstances. Hole drilled in stuck bit, hardened fluted extractor hammered full depth into hole, broken bit extracted.
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All the torque disappeared when the head sheared off. Unless the bolt was cross threaded in the first place the remanent should come out ok. The weld idea sounds good, but you could also bond a bolt using araldite. Make sure the ends are degreased though.
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I agree in general with Hugo's posting (apart from the Signatures -- not as irritating as some, but what purpose do they serve?). I'd just like to add the following comments ...
1. If there's room, I prefer to weld a nut rather than a bolt onto a sheared screw/stud. The weld can be done through the hole in the nut, so saving any damage to other parts, and you then have a ready-made hexagon for turning with a socket. Obviously this would be difficult to apply to very small screws/studs, though you could probably get a couple of weld tacks onto the outside of the nut and this should be sufficient. An advantage of welding a nut (or a bolt) onto the broken item is that the heat will help break the bond. As A.Dent said, Araldite might work, but this may also be better with a nut than with a bolt shank as it can be bonded internally AND around the hexagon if the right size nut is chosen.
2. I agree that tapered stud extractors like Easi-outs don't always work. I've had a high quality set for many years but cannot recall a success with them. However I must admit I've resorted to them only after trying out simpler techniques, like hacksawing a slot for turning with a screwdriver -- sometimes with two blades in the hacksaw frame to make a wide enough slot. I haven't come across the parallel extractors mentioned by Carrick - they sound like a good idea.
3. I always prefer a proper penetrating oil to WD40. I think WD40 is a handy 'all-purpose' spray but never as good as using the stuff made for the job.
4. There's also the age-old practice of simply tapping the broken bolt undone with a chisel held at an acute angle. This can sometimes be surprisingly easy if the angle of the chisel and it's sharp enough to get a bite but not so sharp as to take off lumps from the remnants of the bolt.
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I agree in general with Hugo's posting (apart from the Signatures -- not as irritating as some, but what purpose do they serve?).
I suppose they may seem irratating but I'm just having a bit of fun really.
1. If there's room, I prefer to weld a nut rather than a bolt onto a sheared screw/stud. The weld can be done through the hole in the nut, so saving any damage to other parts, and you then have a ready-made hexagon for turning with a socket.
>>An advantage of welding a nut (or abolt) onto the broken item is that the heat will help break the bond. As A.Dent said, Araldite might work, but this may also be better with a nut than with a bolt shank as it can be bonded internally AND around the hexagon if the right size nut is chosen.
Spot on Dizzy - excellent idea!
hacksawing a slot for turning with a screwdriver -- sometimes with two blades in the hacksaw frame to make a wide enough slot.
I suppose if you cut into the casting slightly you wouldn't do any harm, assuming the remaining part of the bolt is flush with the casting
3. I always prefer a proper penetrating oil to WD40. I think WD40 is a handy 'all-purpose' spray but never as good as using the stuff made for the job. 4. There's also the age-old practice of simply tapping the broken bolt undone with a chisel held at an acute angle. This can sometimes be surprisingly easy if the angle of the chisel and it's sharp enough to get a bite but not so sharp as to take off lumps from the remnants of the bolt.
Agree with both these points Dizzy. I'll need to get some penetrating oil. Which is the best to use?
Also, I suppose tapping with the chisel would loosen the bolt and give you a dent to use a driver etc in it.
****Signature? - Ideas on a postcard please anyone!****
****We never stop learning****
Hugo
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Hugo,
I'll ignore the signature(s) ... this time!
In answer to your question, I'm not sure which is the best penetrating oil to use but I find the old favourite Plus Gas to be very good. Except that it is in a can with a rigid spout that (a) won't let you put the stuff where you want it to go in confined areas and (b) lets the stuff run out on the floor when trying to do (a). I've been intending to transfer the Plus Gas can into a small pump-type oil can complete with a flexible spout that I picked up for £1, at a flower show of all places!
As you probably know, diesel fuel is also an excellent penetrating oil. We use it to free steam railway locomotive parts and it is amazing how well it works. If the parts are badly seized we have sometimes left them soaking for weeks. Not a good idea for your everyday car but a railway locomotive can take 10 or even 20 years of work to restore so leaving the parts to soak in a bucket of diesel for a couple of months is of no inconvenience at all!
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Dizzy, like yourself I've never had any luck with Easi-outs.
Snap on tools sell the parallel extractors I mentioned, they're expensive but might save their cost on one job. Agree with Plus gas recommendation, excellent stuff - been about for years.
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Just a couple more points ...
Hugo, I hope you haven't taken my comments about signatures to heart. Yours are not anywhere near as irritating as some and it just happened that, in replying to your posting, I took the opportunity to let my thoughts be known about signatures in general. We have lost a brilliant contributor known as Toad of Toad Hall who kept us informed and entertained in a most enjoyable manner but always ended with a signature that irritated some -- though not myself as it happens!! I think criticisms of his signature helped lose him and I wouldn't want the same to happen to yourself!
Back to the subject: In the absence of Easi-outs or other stud extractors, the tang of a workshop file can be tapped into a hole drilled in a broken screw/stud and will grip quite well for turning. *Warning, utmost care needed when tapping the file as it can shed eye-piercing splinters!*
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As an absolute last resort if nothing else works, and the only alternative is taking the engine out, is it possible to make up a bracket that can bolt on somewhere else?
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Took the car in today finally to have the snapped off air con bolt removed and refitted. When I phoned to enquire was it ready I was told he was having trouble finding the right belt. He also suggested I might want to try Vauxhall!
Anyway on entering premises to collect vehicle he informed me that he had managed to get one from Vauxhall but it won't be there until Wednesday. So hopefully Thursday when I take it fingers crossed!!!
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Hi Daz - have read your Omega posts and sympathise thoroughly. Whilst I can't offer any advice I would just say that I hope you get it sorted once and for all - you seem to have had more than your fair share of problems. Good luck!
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Thanks Volvoman,
Ironic thing is when it goes well it's a lovely car to drive and even to be stuck in traffic in.
However, I am worried about its upcoming MOT and what will go wrong next!
Daz
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Daz...did you sort your autobox out? IIRC your last 'Omega challenge' was that the autobox was 'off' or something bizarre???
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No sadly not yet!
I have tracked down an independent Vaux specialist who I will be commissioning to do a water pump/cambelt/tensioner change plus look at the gbox when funds permit!
Daz
Gbox seems currently OK apart from kick down sometimes does not work but no engine managment light appears!
btw what does IIRC mean!
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IIRC - If I Recall Correctly
H
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Aha, one mystery solved, just the gearbox to go!
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