Disco 1 Broken belt pulley bolt - how do I take it out?

300Tdi

Whilst on a drive rev counter stopped working, battery light came on and I lost power steering. Just as I thought the belt had come off, but not for the reason I suspected. This bolt had broken off and now the remaining bit is stuck in the water pump housing, but that's not all: A year ago the threads in the housing had shredded off, probably due to my ignorance, and being nowhere near a hardware store for getting a helicoil, I had to fit the bolt back with some sort of epoxy cement that managed to keep it in place.

A few weeks ago I noticed a screeching from the belt, it seemed that the nut on that stud had come off loose and the pulley was coming away from the housing. I tightened it back by hand a little bit harder, however still trying to be careful so the threads wouldn't shear again, and even tried to check with a torque wrench I have... all I know is it was looser than 30Nm. I tried to look it up in the manual but could not find a torque spec for this.

Anyways, this is where I am. How should I go about taking it out? A drill? Use a grinder on the surface and try to unscrew it with a flathead screwdriver? I'm not prepared to spend 300 pounds on a new housing at the moment.

That seems to have sheared off surprisingly flat.
I'd drill it out, starting with a drill bit the same size as the hole to centre-mark it, i.e. not trying to drill it out with it, then go up the sizes until it comes out.

But once you have got it out you'll still be in the same predicament with the bodged up hole with stripped threads. Can you not get a secondhand one or at least get it properly helicoiled?

Stanleysteamer said:

That seems to have sheared off surprisingly flat.
I'd drill it out, starting with a drill bit the same size as the hole to centre-mark it, i.e. not trying to drill it out with it, then go up the sizes until it comes out.

But once you have got it out you'll still be in the same predicament with the bodged up hole with stripped threads. Can you not get a secondhand one or at least get it properly helicoiled?

Click to expand...

Thanks for the reply.

Once it's out, and if I use a drill to take it out, I can easily drill a 10mm hole and install a helicoil I bought in anticipation...

But I think the radiator will have to come out for me to have room.

P.S.: I just found a thread on another forum saying the correct torque is 45Nm, so mine wasn't so tight. I'm wondering why it would break like that then?

I would kill two birds with one stone, and remove said housing then do cambelt whilst in there, and this way if you cannot repair the thread properly a machine shop will.
Do it properly and it will last forever.

lynall said:

I would kill two birds with one stone, and remove said housing then do cambelt whilst in there, and this way if you cannot repair the thread properly a machine shop will.
Do it properly and it will last forever.

Click to expand...

Hi,

Does the cambelt have to come off to remove the housing? It was just done probably 100 miles ago. I just need to get it back on the road desperately right now and reliably, fingers crossed. It will take at least a week to get the new stud though.

No its only the belt cover plate, might need a new main gasket, dont forget the silly little small round one.

I was lucky enough to find a used water pump housing with good threads for 60 pounds, as I don't have the time or means to remove the broken stud and fix the threads on mine at the moment. Struggling to find a stud here in North-Eastern Europe, but I've heard that some people just use a long enough bolt screwed from behind the bracket? I would prefer to do this as I could have a bit more faith in that tensioner not coming off next time.