Rounded valve cover hex head

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Goddamn valve cover screw is rounded. How do I get it out ?

At my wits end

Get the Torx bit that just slips inand hammer it in then carefully turn the bolt out. Put some anti seize on the new ones and don't over tighten them.

Make sure you use the correct tampons for your bike.

Small sharp chisel, so it can bite into that groove at an angle. Tap tap tap, it will come out.

I've had some luck with left-handed drills. Try and get the center with a small drill, and then increase the size. If it still doesn't loosen, use a 1/4" one to take the top off the bolt, and then with the cover removed, hopefully can get a pair of vice-grips on the remainder.

Here's my method, in addition to the other fine suggestions:

Use a center punch for locating drill bits, and make a nice healthy divot on a place on the bolt head with some clean real estate. The closer to the edge the better, but far enough inboard that you don't peen the outer circumference out. Three good whacks, depending on material. Then angle the punch so it's pointing counter-clockwise, and make some firm, measured taps in the direction of removal. If you start to deform your divot without the bolt breaking free, repeat at another clean spot on the bolt head.

I work on industrial machinery and have to do this A LOT! This works on probably 80% of the broken bolts I have to deal with, and is particularly effective on bolts that have broken off flush.

Use patience and care, (and plenty of spray lube) and chase the bolt out with the center punch - the extractors stay in the tool box, as God intended.

+1 on the Torx suggestion. You can also use a dremel to cut a slot across the top and use a flathead screwdriver.

These screws don't seem particularly well made.
I always use good quality tools but the hex key doesn't feel like a good fit.

kiwi dave wrote:

............I've had some luck with left-handed drills..............

This^^^
Never failed me yet, and since it's not likely that these valve cover bolts are torqued down to humongous specs, It will come out easy for you.

Grisonut wrote:

kiwi dave wrote:

............I've had some luck with left-handed drills..............

This^^^
Never failed me yet, and since it's not likely that these valve cover bolts are torqued down to humongous specs, It will come out easy for you.

I have to agree with this. I used a left-handed drill to remove a valve cover bolt stem of which the head had snapped off. Worked like a charm.

sideshowbob wrote:

Small sharp chisel, so it can bite into that groove at an angle. Tap tap tap, it will come out.

That worked perfectly! Thank you so much.

Go with Petes suggestion first me thinks. Don't ask how I know this is the easiest and best way.