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Old 03-22-2012, 07:20 AM   #1
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Default Removing broken valve cover bolt

Sooo... stupidly back in September I overtightened a valve cover bolt and it snapped clean off into the head. There is nowhere to grab onto it as the break is level with the head. It's quite a small M10 bolt, so what would be the best way to get this out? Silly me decided to leave it when I left for Europe and now I just realized I need to fix that before I can get my car back on the road when I get back in April.
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Old 03-22-2012, 11:14 AM   #2
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I just did this a while ago. Apparently those bolts are meant to last 4,999 tightenings and not 5,000.

I was pissed that I had to remove the valve cover and buy yet another $23 valve cover gasket, however if yours is flush with the head I might either consider running without it if its in the center or taking it to a machinist. Feel free to use an easy-out at your own risk.
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Old 03-22-2012, 11:16 AM   #3
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How far in did it go? Any chance that there is some exposed below the lip on the head and you could unscrew it from below? If that is not a possibility I would probably just run without that one.
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Old 03-22-2012, 11:22 AM   #4
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No it's not visible from the bottom. I did run without it for a bit before parking the car for the winter and it was weeping out of that area. I'm thinking to just drill it out and if need be throw a helicoil in. what a pain in the ****.
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Old 03-22-2012, 11:33 AM   #5
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Old 03-22-2012, 12:56 PM   #6
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I did this last year. Luckily I had enough exposed when I took the valve cover off that I was able to grab it with a pair of needle nose pliers and twist it out.

I scrapped all the stock bolts and just brought grade 8 ones at the hardware store.
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Old 03-22-2012, 12:57 PM   #7
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Yeah, the ironic thing is... I was running ARP bolts on all of them but had lost one when I changed my valve cover gasket. I put one of the stockers in, and right as it was getting tight it just gave way. I'm thinking I may replace them all with a stud/nut combo.
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Old 03-23-2012, 03:38 AM   #8
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Weld a nut to the top of the broken bolt. Owning a welder is the key to this fix though.
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Old 03-23-2012, 03:41 AM   #9
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Amazon Amazon
<- This tool worked wonders on my oil pump housing screws.
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Old 03-24-2012, 10:40 AM   #10
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Drill into the center of the bolt with a tiny left cutting drill bit and use an extractor. It should come right out and leave the threads undamaged if you don't fack it up.

Make sure you cover the head so no metal shavings end up in the bearings.
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Old 03-24-2012, 02:34 PM   #11
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Aren't all the head cover bolths through holes? Just get a drill smaller than the threads, and drill it out. Hopefully, the drill will catch, and drive the broken screw right out the bottom. If not, you can now drive a drywalll screw into the hole and thread it on through.
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Old 03-24-2012, 07:12 PM   #12
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You can always try cutting a flat on the bolt and turning it out with a screw driver.
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Old 03-24-2012, 11:46 PM   #13
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Quote:
Originally Posted by triple88a View Post
You can always try cutting a flat on the bolt and turning it out with a screw driver.
This. If you get a fine cutoff wheel on a dremel, even if you cut into the flange a little bit on either side of the broken bolt you will be able to slot it enough to get a screwdriver in there. You will likely find that it isn't tight in there at all.

Before doing that you might just try picking it backwards with a dental pick.
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Old 11-14-2014, 08:17 PM   #14
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Quote:
Originally Posted by Stein View Post
This. If you get a fine cutoff wheel on a dremel, even if you cut into the flange a little bit on either side of the broken bolt you will be able to slot it enough to get a screwdriver in there. You will likely find that it isn't tight in there at all.

Before doing that you might just try picking it backwards with a dental pick.
Holy crap this is gold! Pure simplistic genius. Thanks! (Also holy thread revival!!)
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