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S3 Valve Cover Bolts Binding, Any Chance of Not Snapping Them Off?

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Old 12-11-2017, 06:38 PM
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zekgb
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Default S3 Valve Cover Bolts Binding, Any Chance of Not Snapping Them Off?

Eighteen months after I dropped the engine back in I decided to go back in to take a look at the cam tensioners which I suspect are the cause of some fairly pronounced ticking/rattling when cold. When I did the heads I decided not to update to S4 tensioners and didn't know about the updated spring cap which is a potential solution for a noisy tensioner. Armed with the required parts from Roger I dove back in only to find to my surprise that even after only 12k miles or so that at least two of the valve cover bolts on the driver's side are showing lots of resistance which indicates they have galled to the shoulder bolts in the head and will probably snap if I force the issue. Is there any combination of heat/cold or other tricks I can use to potentially free them up or am I doomed to the horrible job of drilling the broken bolts out after I inevitably snap them?
Old 12-11-2017, 11:48 PM
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I take it you didn't use anti-seize when reassembling......
You can try soaking with PB Blaster for a few days and whacking the bolt heads to "shock" the corrosion and perhaps release.
I know with the water pump bolts a mini impact gun works wonders......
If you've already stressed/twisted the bolts though, you're likely going to be drilling.....
Old 12-12-2017, 09:53 AM
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SwayBar
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Did you use a torque wrench when you reinstalled the covers?
Old 12-12-2017, 11:08 AM
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hwyengr
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If I could glom onto this thread, what is the current status of using S4 cam cover bolts on the S3. (Somewhat topical if you end up having to drill...)

Some say it works, some say it doesn't. If it works with modifications, what do you need in addition to the bolts?
Old 12-12-2017, 11:56 AM
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Kevin in Atlanta
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Small butane torch is your friend here. Heat up the block near the bolt and work the bolt in and out until it is completely out.
Old 12-12-2017, 02:58 PM
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zekgb
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Originally Posted by SwayBar
Did you use a torque wrench when you reinstalled the covers?
Yes I did, engine was assembled on a stand 12k miles/18 months ago.
Old 12-12-2017, 03:28 PM
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davek9
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S4 Bolts will work on S3 covers, need to cut down a few of the Rubber washers to get a good byte on some of the short ones.
Old 12-13-2017, 09:40 AM
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Big Dave
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Oddly enough, the bolts on my S3 that were seized and snapped did not "feel" seized. Hard to tell if the bolts are breaking free....or snapping off...until it's too late. Best bet is heat, but like Rob says, it may be too late already.

I have S4 bolts now. Expensive upgrade!
Old 12-13-2017, 09:47 AM
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hacker-pschorr
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Need to "wake up" the threads. With the proper sized allen firmly inserted, whack it a few times with a hammer. The bigger the better, just don't get carried away and damage something else.

I do this with every fastener I suspect will be a problem, especially allen bolts since this will also help ensure the wrench is firmly inserted to reduce the risk of rounding it off.
Old 12-13-2017, 12:19 PM
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davek9
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Also if the Shoulder bolt is coming out of the head and its the top bolt that is seized to the shoulder bolt, then the entire assembly can be removed, you just need to remove all at the same time and lift the cover off.
Had one cover that had three seized this way, just had to keep going at each bolt a bit at a time.Then deal with getting them apart on the bench.
Old 12-13-2017, 12:25 PM
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S4 Cam Bolts on S3 covers, if you do this on the car, you will need some short (cut down) Hex wrenches

Dave



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