[Closed] Car mechanics - helllpp!

How long is the threaded hole?
Can you see how damaged to thread is? Any chance of cleaning the damaged thread? If you can, you may be able to get the bolt past the damage to some good thread, but depends how deep the hole is.
Further bodge would be to drill out the tapped hole (all the way) and use a longer bolt with a nut on the other side.

You can get a tap and run it through, sounds like I you may have caused damage to the first few threads.

If it's a through hole you could run the bolt in from the other side without the shock in position, just to re-form the thread.

It is a 3-4" long bolt, m12 or so.
Cannot drill and nut as it is disc mount, hub carrier, suspension tie all in one etc
The top hole on this pic.
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If the bolt is 4" long, how deep is the threaded hole? If it's also 4", 4 threads isn't going to make much difference. Clean with a tap and start carefully.

Caveat, I'm not a mechanic and closely fit the STW stereotype 🙂

Sometimes you can find the original thread, so try keeping it straight and screwing in. Tryremoving the whole thing from the car.

Bolt is 4" long, but only 2" in in hole as rest is the end of the shock absorber.

Get a blind hole/bottom tap and tap holder for the thread size

Only do molgrips idea if you want to completely spacker it thats nothin more than luck. - although for odd sizes i have made my own tap out of bolt + bench grinder and saved it that way.

If you don't have a tap to hand, you might be able to try this.

If the threads on the bolt are damaged too then you will need to fix that also. If the bolt is OK and the hole is only a bit damaged molgrips technique might work, but it usually only works on ally not cast iron. A bolt thread gets max strength with only a few threads so unlikely to be a problem once you fix, its shear force on the bolts, so as long as it tightens up OK you are absolutely fine.
If you haven't got/cant get a tap and die, try cleaning up the bolt with a fine file and try molgrips idea carefully, dip in oil first, maybe just maybe.

^mcmoont I think that is what I need - if that does not work, then it is goosed and I will need a new hub carrier... 🙁

Mcmoonter has it - thats sinilar to what i do when i dont have a tap.

Is it your only car and do you need it back on the road for Monday? I have got a tap set but I'm probably about fifty miles away. It should be salvable. Failing that, you should be able to get a tap from Halfords on a Sunday.

If you try and re tap out the hole try and use a 1st tapered tap so it doesn't follow the knackered first few threads. If it does the hub will be scrap. You really need a 1st 2nd then plug tap. I would be surprised if halfords has one of those.I would drill out the first few knackered threads, if there is only 4 cross threaded threads I wouldn't worry.

If you can't save the thread as described above then you may be able to helicoil it?

Not a tapered thread but a tap with a large lead in to get past the damage. Any engineering shop would be able to re tap it or fit a M12 helicoil.

Didnt see it was 2 inch deep. Taper tap for sure ! Youll probably just nesd the taper tap to save it tbh if only the forst threads facked.

I'm failing to see how you trying to carry out a job incorrectly and stripping threads is a duff vw design.
Take the outer spring pan bolt out, remove spring, flex pan down and you will have straight access to the bolt, start the bottom bolt first make sure it looks to be straight and you might just catch an original thread.

You have to be good/lucky to get it right with the spring in place. Wishing you good luck.

Any tool hire shops around?
Tap hole as others have said, use cutting fluid if possible or oil to lube tap. If doing it yourself make sure you work the tap in using small turns back and forth, back and forth. Same with die, don't be tempted to screw all the way in a oner... It may jam and break!!!
Die to clean up bolt = all sorted 😆
Standard fix.
Would not be too keen to use the heli coil idea

Cheers all.
pacerc200 - I tried removing that bottom member / pan, however every bolt is seized tight on both sides. On the other side (that went really simply), the bolt I am referring to I had to soak in release spray, then use a jack to lift end of spanner - it actually lifted car up off the stands before releasing...
Starting to see why all the garages wanted £400+ for the job 🙁

Any tool hire shops around?

First rule of home mechanics.

3 ft long half inch drive breaker bar and face drive sockets.

Spanners wont shift anything thats been in there for a few years on our roads and multi point heads on ring spanners round bolts for fun ( based on my experiance with 26 year old land rover and 14 year old frontera.)

Matt - The Scrwfix in Stirling have a couple of tap and die sets in e.g.

http://www.screwfix.com/p/carbon-steel-tap-die-set-51-piece-set/11449#

They are open 10-4 tomorrow here

http://www.screwfix.com/jsp/tradeCounter/tradeCounterDetailsPage.jsp?id=4000002

Be insanely careful with carbon steel taps

No jerking at all and only small advances.

If you snap that tap in there you will cry.

Or this looks like a better set - http://www.screwfix.com/p/hss-steel-tap-and-die-set-51pc/12834

Or this one from Halfords (also in stock in Stirling) http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_236397_langId_-1_categoryId_165572

3 ft long half inch drive breaker bar and face drive sockets.

At that cost, I would be better to buy a new hub at garage, as chances of c*cking up are high with me it seems..

At that cost, I would be better to buy a new hub at garage,

You must know some cheap garages. 🙂

Nothing wrong with helicoils but they can be tricky to insert. A first tap should be fine. Don't use any oil or cutting fluid you don't need it for cleaning the thread out. It may also affect the bolt torque and you don't want that bolt loosening off. If you have to, put some copper grease on the shoulder of the bolt as that is where it will stick.You really don't need a new hub it will be fine, trust me I have repaired far worse and never had a problem. You are to be commended for having a go. The whole exercise is to save money.

4 threads of a M12 is 7mm out of the 50mm you reckon is in there. Just get a 12mm drill & take the first threads out, a few mm at a time.
And it's a big drill, you don't want the thing spinning at max rpm.
Hold the drill nice & steady, & in line with the hole.
You could grind down a bolt so it's a 90deg quadrant, & pop it down the hole, engage the thread & try working it outwards. Tricky but it's worked before.

Matt, If it the same as the Golf/Scirocco its a metric fine thread. Ive crossed threaded these loads of times on our race cars. When mounted in the car the angle that it is tapped is a lot steeper than you think. The proper bolt has a lead on the end to locate it and make it easier to start. I know it sounds brutal but we just get a bolt with a longer lead and drill out the first few threads. Where are you based..?

I am in Dunblane.
It is at an odd angle to the casting - and yes had a lead. On the other side, i just had to jack up the suspension *slightly*, then hold the new shock compressed and in line - a bit of wiggling, a few 'missed' stars and away....
Nowhere in Stirling has an M14 bolt or tap n die set, so day off tomorrow to sort it out.

20/20 hindsight .... That's the trouble with home mechanicing.... A lost weekend, a days leave a a less than perfect repair. A £400 garage bill starts to look more attractive.

Hope you get it sorted. Should be straightforward once you have the right tools.

Whooooooooop. We're done and on.
Last attempt at clearing start of threads on hub carrier and suddenly a perfect wee coil of metal dropped out, so gave it a go with the cleaner up bolt.
Phew, and still a good few quid saved. We did not have luxury of garage vs weekend. ..

Nice one Matt - those sort of things usually happen to me! Glad you got sorted.

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Good news that matt, saves doh.

I had to resort to the good old universal rotary spanner removing my body mount bolts today they were not for shifting at 15 years undisturbed !

Got the oil sensor changed and the oil + filter and air filter done this morning thought 🙂