Dogbone mount bolt not tightening

Silva bullet

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Evening everyone as some off you may know when I upgraded to a 3 inch downpipe and decat recently all is still well with that but today I got under the car to see why my engine was knocking on bends on bumps.

So I tightened all subframe bolts and noticed that the shorter bolt on the dog bone would not tighten so I think I need to heli coil or use an insert or something.
I have ordered both bolts from dealers should be coming tomorrow.
There is a kit on ebay but I don't know which one to buy as I don't know the m something size so if anyone knows I would be 1 happy man lol.
As it stands my s3 is All over the show and it's making me drive like 20mph with no traffic..
Just to add to the pain my 2 of the 4 steering rack bolts have snapped but I have known this for a week or so already got 4 new bolts and bolt extractor just need to get a few steel cutting drill bits first before I commit..
Just when I found a nice b road ((rivington) where generally you only see motorbikes and police there..hey aye rivis will have to wait..
Thanks everyone...Silva bullet
 
Its an M10 bolt.. I think its a 1.5mm pitch

<tuffty/>
Evening tuffty thanks so much mate for the info I have therefore ordered a kit off ebay.
Kit should be with me in 5 days I just have to drive slowly until then..
Your info is always valuable big man so thanks again bud..Silva bullet
 
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Just as a word of warning, if drilling the snapped bolts out is going well, and you've got it started nice and straight and central, I'd just continue drilling and leave the bolt extractors in their box. You can usually drill it out to the point where near enough only the thread is left then break or wind out the rest with an old scribe or sharp punch. I say this because if you're unfortunate enough to snap the extractor in the bolt, you're in a whole world of pain trying to get the remains out.

Extractors can be good if the bolts snapped because of over-torquing or abuse, so the remains are relatively loose in the hole, but if it's snapped because the thread's seized then there's a good chance of the extractor snapping too. You certainly want to make sure to use the largest one you can to reduce the chances of snapping it, but I (and most people I know) have had much better success drilling bolts out, or even better, welding a nut to them, than using extractors. Reverse cutting (counter-clockwise) drill bits are good for loose-ish snapped bolts too, as they tend to wind it out before you get too far in.
 
Just as a word of warning, if drilling the snapped bolts out is going well, and you've got it started nice and straight and central, I'd just continue drilling and leave the bolt extractors in their box. You can usually drill it out to the point where near enough only the thread is left then break or wind out the rest with an old scribe or sharp punch. I say this because if you're unfortunate enough to snap the extractor in the bolt, you're in a whole world of pain trying to get the remains out.

Extractors can be good if the bolts snapped because of over-torquing or abuse, so the remains are relatively loose in the hole, but if it's snapped because the thread's seized then there's a good chance of the extractor snapping too. You certainly want to make sure to use the largest one you can to reduce the chances of snapping it, but I (and most people I know) have had much better success drilling bolts out, or even better, welding a nut to them, than using extractors. Reverse cutting (counter-clockwise) drill bits are good for loose-ish snapped bolts too, as they tend to wind it out before you get too far in.
Hello Robin I see what you mean when you say if drilling is going well don't use the extractor as if that breaks I'm in a whole load more of bother lol..
I thought of taking the car to a welder but I remember when I had a wheel bolt welded to another bolt when I rounded my original bolt..basically the scrapper /welder charged me 65 notes to do the job plus leaving the car with his oily hands over night then I realised he must have had the engine running for good 3 4 hours or so as o had lost off fuel missing.
On my dodbone issue it's a only a new Coul job as the old bot keeps spinning and not tightening at all.
And for the 2 steering rack bolts that have snapped whilst tightening i think it would be easier like a cowboy like me to do lol thanks for your input buddy specially at that hour of the day real gem is what up are..
Will update once my ebay helicoil and cabalt drill bit arrives..thanks again mate silva bullet.
 
Hey everyone I got my heli coils and hss drill bits so gonna crack on with 2 snapped steering rack bolts and the dog bone mount bolt that keeps spinning and not tightening.

Dry fitted the helI coil with o dog done mount bolt and it fits perfectly like a glove.
I will update tomorrow and tell ya how it goes..many thanks silva bullet
 
Hello everyone jus a quick help required please..
Literally getting ready to go to my car gto tools/foods packed up as I'm doing my dog bone mount bolt heli coil jobby.
I received my ebay heli coil kit which includes everything needed apart from a t piece type spanner you put onto the tapping drill bit (which creates the round engravings..
From what the forces required to engrave the new tap I defo wount be able to do it with a adjustable wrench.
There are afew vids on the tube and they all use this t piece type wrench to bore the tap
In does anyone know the name of the tool..thanks everyone
.silva bulle
 

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You need a 'T' type tap wrench really mate,something like this...
Download
Maybe somewhere like Screwfix or Toolstation would have them,or an Ironmongers.I would smear the tap with a little oil and as you are 'cutting the thread you have to keep reversing the tap 1/4-1/2 turn for every full cutting turn.That way it helps clean the thread as you go.

When you're doing it,you will feel the difference in resistance between cutting the thread and then when you reverse and start cutting again,it will feel easy until you reach the part where you're actually cutting the thread again.

I hope that makes sense.
 
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Try and be patient as when I did my camper van exhaust studs they were hardly the straightest. Also when you are drilling don't push too hard, you don't want to do too deep or like I did drilling out a snapped bell housing stud straight through the back and into my push rod tubes, 2 days before getting the MOST and using it for holiday.

Why did you not use those inserts people buy?
 
Evening Stuart b I will be steady as he'll to the point my hand will shake lol.
I have never done anything like drilling metal so it's going to be a learning curve for sure I'm only use to drilling wood.
Thanks for the heads up my man and will update when my tap wrench tool arrives.. thanks mate.. i was advised by a mate to use heli coil as he had always had good results with them..SILVA bullet
 
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Evening tcg so that's the damn things name.
I was googling all sorts but never came up with a picture as you very kindly posted.
I've ordered a set which also includes a couple of m size cutting dies for any future tapping jobs.the set was a fiver and should arrive by Thursday so looks like it's shaky engine until next weekend lol.
Thanks alot mate for your input as I would given up and not ordered anything as I was clueless.
Thanks again mate I will update as I get my set in will also take pics as it's only gona help another member...Silva bullet
 
Hello everyone hope your all cool.
I managed to place a heli coil into the dogbone mount hole. .
Then took me ages to line up subframe holes got all tight ok then put wheels back on and my lungs almost came out my ribcage along with my over pressured heart..
Im not sure 100%but I think I may have snapped the 2 remaining steering rack bolts 2 bolts were already snapped before this but I was able to drive as 1 bolt on each side of the car were snapped this is what leads me to think that 2 remailing ones are now snapped.
This all happened after I done the catch can that went perfect had the car running on axel stands for a hour or so and it all held up well.
I'm so gutted as Im back to work on Wednesday night...silva bullet
 
Morning everyone today it's subframe off job to see why I have to steering connected.

I suspect some more power steering rack bolts have snapped so it's OK weather wise only time will tell.
I really need to get it done today as a must..
 

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Hello mate the bolt in trouble now is the smallest bolt out of the two the bigger one I did a heli job on is holding up well.

Why I asked is because this bolt is smaller so I wanted to just ask as to the length off the dye and the drill bit to drill out..
 
Bolt is shorter as it only goes through a thin plate... Longer bolt goes through the bush and needs a longer bolt... Thread engagement will be similar... Use a screwdriver and poke it in the hole... Measure the depth from that..

<tuffty/>
 
Bolt is shorter as it only goes through a thin plate... Longer bolt goes through the bush and needs a longer bolt... Thread engagement will be similar... Use a screwdriver and poke it in the hole... Measure the depth from that..

<tuffty/>
I need to change the dog bone on my TT, but these issues are a concern. Is these issues from overtightening, corrosion or hitting the road?
 
all of the above... typically its down to animals using air tools to wind a bolt into magnesium alloy when doing clutch changes

<tuffty/>
 
I think these problems are due to mainly overtightening, I replaced mine and it was the original with 118k on it. Bolts came out relatively easy but it had actually corroded itself partly to the subframe. New bolts in and correctly torqued up in 2 minutes.
 
Tuffty thanks for the info mate..ahh I see what you mean now the screwdriver in hole to measure.
That is great then now I think I'll be able to do this myself..thanks again
 
Georges3 your right there over the years have seen dosens of mechanics using a air rathet to loose and to tighten my dogbone mount bolts and they never seen to renew the bolt.
So it had to ground on me..not happy..
Ibe bought a cheapo torque wrench 1/2 from bnq so once I've prepped the new hole I will for the first time torque up to the right spec.. thanks for your help mate..
 
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I've learnt so much but it had to be through time and money.monkey mechanics always taking short cuts but not pay cuts..
Thanks for the reply Stuart b.
 
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