Removing broken valve cover bolt
#1
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
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.
![vash](https://www.miataturbo.net/images/smilies/vash.gif)
#2
Cpt. Slow
![](/mt2011/images_td/ranks/supporter1.gif)
iTrader: (25)
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,326
Total Cats: 1,181
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
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.
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.
#3
mkturbo.com
![](/mt2011/images_td/ranks/supporter1.gif)
![](/mt2011/images_td/ranks/admin.png)
iTrader: (24)
Join Date: May 2006
Location: Charleston SC
Posts: 15,188
Total Cats: 1,684
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
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.
#11
Elite Member
iTrader: (21)
Join Date: Jun 2007
Location: Rochester, NY
Posts: 6,614
Total Cats: 1,274
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
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.
#13
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Before doing that you might just try picking it backwards with a dental pick.
#14
![Lightbulb](https://www.miataturbo.net/images/icons/icon3.gif)
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.
Before doing that you might just try picking it backwards with a dental pick.
![Party Kitty](https://www.miataturbo.net/images/smilies/birthday[1].gif)
Thread
Thread Starter
Forum
Replies
Last Post
bigmackloud
Miata parts for sale/trade
19
01-08-2021 11:24 AM
stoves
Suspension, Brakes, Drivetrain
5
04-21-2016 03:00 PM