Subframe captive bolt damaged

[quicky1980 0]

I have messed up big time!! And dont know what to do.

 

I was in a rush and managed to cross thread and destroy the captive bolts on both sides of the rear engine subframe where the wishbone bolts attatch to.

 

I know this isnt good and Im a pr@t for doing it, but is there any hope? can it be repaired? (beyond tapping) if so whats it going to cost and can a normal garge sort it?

 

argh!!! im so angry!!! :censored:

[quicky1980 0]

has anyone had this happen to them or someone they know? is it saveable?

[Dec 1]

IS it not possible to drill the hole out to a larger size and then tap it for a M10/M12 bolt?

[quicky1980 0]

im not sure as the bolt goes through the wishbone wishbone pivot point. I dont know if a larger bolt would fit through.

[Dec 1]

MAybe get the wishbone removed and properly clamped up so you could accurately increase the size in the front wishbone bushing too? There's quite a thick metal cylindrical section that the orig bolt goes through, so I reckon you could drill that out by a few mm.

[dr_mat 0]

MAybe get the wishbone removed and properly clamped up so you could accurately increase the size in the front wishbone bushing too? There's quite a thick metal cylindrical section that the orig bolt goes through, so I reckon you could drill that out by a few mm.

 

Maybe, but I think you'd be better off getting another subframe..

 

Or I think you can unweld the seams on the subframe and weld a new bolt back in.

 

Or maybe there's room to drill the old bolt, tap it and insert a helicoil?

 

I'd be inclined to get another one though, since due to a certain amount of design stupidity, that's about the only thing really holding the wheel in place. They're not that hard to come by due to low demand and reasonable supply. Question I have to ask though is are all these 2nd hand ones *straight*?

[quicky1980 0]

Its not the subframe unfortunately otherwise I would have replaced it straight away. Its the mounting bolts attatched to the car itself.

[Lee1873 0]

Happened to me a few times now on mk2 gtis......the only fix without removing the subframe & re-tapping or hellicoil....is......cutting open the floor & either drilling through the captive nuts holder or cutting it off & welding in a nut or 2 joined together as i did, back to the floor.....i feel your pain mate its a total nob of a design & was bound to happen as these cars got on a bit with the amount of torque on the bolt your supposed to apply & the frequency of the bushes going

 

HTH

 

Lee

[quicky1980 0]

Cheers Lee, glad to know Im not the only one thats done this. Nice little hint about going through the floor.

Ill let you guys know how it goes, still gutted tbh. more time and money!!

[vdubjb 0]

I was hoping to avoid this yesterday. I jacked the car up and noticed the bolt resting against the sump! Was able to bolt it back down, hope it stays in place...

[flyferrari 0]

Hi Guys,

 

I'm going through this mess at the moment. Before you do anything drastic check out the "official" way of dealing with a stripped thread in one of the captive nuts. As you can see it even includes part numbers for the replacement bolts.

 

Regards

 

Kevin

 

P.s. hope I'm not too late

[quicky1980 0]

Thanks. But, doesnt this just explain on how to retap the captive nut? or am i missing something?

[dr_mat 0]

Thanks. But, doesnt this just explain on how to retap the captive nut? or am i missing something?

 

Yes, but doesn't it also explain what size bolts to use when you've retapped it? I assume, anyway.

[quicky1980 0]

Yes, but doesn't it also explain what size bolts to use when you've retapped it? I assume, anyway.

 

Im not sure as they sound the same as the standard bolt. I could be wrong though.

 

Securing point .........Thread Bolt ............................. Part No.

Front sub-frame........M12 x 1.5 M12 x 1.5 x 100 (10.9)......N 101 418.011)

Rear sub-frame ....... M12 x 1.5 M12 x 1.5 x 100 (10.9).......N 101 418.011)

Sub-frame bracket ..... M10 M10 x 40 (10.9)....................N 100 596.041)

[flyferrari 0]

My understanding is that the captive nut is a blind nut, i.e. has a solid portion above the threaded bit. The doc I posted implies drilling through the solid bit and then tapping it and then fitting a longer bolt (VW part) to secure the subframe. This is what has been done to my car...I hope. If this info is not helpfull then accept my appologies for wasting your time but from your description of the problem this proceedure should help. It beats the hell out of taking an angle grinder to the cabin floor after removing all fuel lines etc. and then welding in a new pair of captive nuts. I would be surprised if you'd get change out of £500 for that!

 

Regards

 

Kevin

[quicky1980 0]

Thanks so much bud, if that is the fact then it will save me a fortune. hopefully!

[quicky1980 0]

many thanks flyferrari. Im going to order the longer bolts now. Glad VW planned for my goofy work skills. thanks again.

[quicky1980 0]

Tried to order the bolts yesterday from VW and they arent able to figure out how to get them for me. I explained what I needed inc item number but still they had no idea. Anyone know how I can get a hold of these bolts? if not looks like ill be going to a shop and buying high tensile bolts to the correct spec.

[bcstudent 0]

I had something similar happen to me on a Mk2 Golf a few years ago, although I managed to break the nut free from its welds. Under the carpet in the car, there's an inspection cover that allows access to the captive nut. It'll likely be a bit fiddly, but I'm sure there's enough room and visibility to retap the nut from the top.