[markyinger]

I discovered that the relay pulley stud is broken off. When I pulled the top timing belt cover off I found that the relay pulley (the small one) was simply sitting there at an odd angle and riding against the belt. It had worn a small groove in the belt. It has also worn a hole in the plastic cover. Fortunately I discovered it before the belt gave out.

It looks like a nasty job to get the broken of stud out of the block. I don't see how it could have received enough force to break the stud. Can I simply leave the relay pulley out? Obviously it has run for some time without the relay pulley.

I discovered this because I heard an odd intermittent jiggling noise coming from this area. I have search forums and found nothing about this problem. Weird! Timing belt last replaced by a VW dealer.

 

[FLipped]

Absolutely not! The belt is designed to be a certain length and the tensionser won't be tight. Drill it out and then use an extraction tool. Pics?

 

[chittychittybangbang]

:needpics:

Absolutely change it. The dealer could have overtightened something which led to it snapping.

Count your lucky stars the belt held.

 

[buggy9]

How long have you heard the jiggling noise?

 

[markyinger]

I got the loose relay pulley out with the stud in. It did not brake off it worked its way out and in the process buggered up the threads in the block some. I was surprised at how little of the stud is threaded into the block. The threads on the other end are flatten somewhat, it appears the nut was loose for sometime. Here are some pictures for what they are worth.

Any advise would be appreciated.

 

[markyinger]

I think the dealer did over-torque the nut on the relay pulley and weakened the threads in the block. I am considering drilling it out and installing a helicoil thread insert. The outside diameter of the helicoil tap is about 1/16 inch in diameter bigger than the 8mm stud. Do you think there is enough metal in the block that it would be safe to do this repair of the threads? I really see no option.

 

[chittychittybangbang]

Is that the entire stud? Does the upper part or the lower part go in the block? It looks like the lower part does and there's not much there.

I'm confused - if they overtightened the stud - why would the nut be loose? And how in the world could they overtighten it that much?

I guess it's not possible to clean the threads so if there's no option there's no option.

 

[markyinger]

Yes that is the entire stud. The lower part, the end with fewer threads, goes into the block. I am guessing on the cause being that the nut was overtightened and that stressed and pulled the threads in the block and then eventually everything loosened up and eventually came apart.

As the stud worked further and further out of the block it put more and more stress on the threads in the block. About the outer 1/3 of the threads in the block are very damaged. There is really no way I could start a tap and expect it to meet up nicely with the remaining good threads.

Yep, no option but to drill it out and put the thread insert in. Surely there is enough meet in the block.

 

[Franko6]

stud removal

Here's the good thing about those studs... they aren't in there very tight.

Ther are several ways to remove the stud...

1. Use a center punch or chisel and tap the end of the stud counter-clockwise. Usually there is a bit of the stud still protruding, so that helps.

2. Center-punch, drill and easy-out. Like I said, it doesn't usually take much to remove the part of the stud left in the head.

3. Weld a small nut onto the broken stud. This is the trickiest method, requiring specialized equipment and skills, but it's almost infallible. All you need is a little bit of room to manouver.

 

[markyinger]

This is a wrap up of the relay pulley stud coming out of the block post I started. Thanks for your comments.

The entire stud came out, it did not break off at the block. In the process of working its way out it destroyed the threads and left an slightly ovoid hole. So I drilled the hole in the block out to 27/64" and the threaded it with 12mm x 1.25. Then I installed a Keysert thin-wall steel thread insert. These are made by Alcoa Fastening Systems. They use a mechanical locking system. The keysert is just slightly below the surface of the block so that the relay pulley shoulder contacts the block not the keysert.

I had to buy the relay pulley stud and timing belt covers from the dealer and of course they soaked me for them and were rude in the process. At least this time I was happy that I could just give the parts guy a list of parts numbers.

Why it came out is speculation, but I suspect that during the last timing belt change (done by the dealer) the relay pulley nut was over torqued weakening the threads. In my experience I know when I have over torqued the threads because I can feel it when the threads begin to give, hate that feeling. The 2006 Golf has 203,000 miles on it.