Hex bolt removal

[sgaar]

The PO of my 560 didn't give much care to the motor mount bolts when taking then in and out. The result now is that the hex is less hex and more round.

So to get the bolt out I figure that I need something like a Hex Head Multi-Spline Screw Extractor



My question is now how big of an extractor I should get. The Hex is a 10mm (when it is not round) and 11.2mm when round (diameter). The extractors I have found are SAE so the closest is 7/16".

I should be able to use the screw extractor without drilling the bolt, or at least I hope so since the bolt is difficult to access with a drill.

Any advice anyone have would be great.

BTW, I found this place where they sell the tools: Browse the MSC Big Book The extractors are at the bottom of the page.

Thanks,

[donbryce]

How about getting 2 used or new replacement bolts first, which you'll need anyway, then use those heads to experiment with various metric and standard bits or extractors that will be a 'hammer in' fit to the old ones?
(I assume you are referring to the 2 long bolts that go into the mounts from below. These shouldn't be in there that tight. I loosened mine for the first time since it left the factory with lots of penetrating fluid on the top plate nuts first.)

[sgaar]

Well, I started looking for alternatives and found this: http://sockitout.com/american_sockethead.html where you get a hex shaped steel pin that is hammered into the bold and then you can turn it.

I found it on http://www1.mscdirect.com/cgi/nnsrhm and once I got myself positioned under the car, the pin aligned I tapped it a few times with a hammer it came loose with the help of a breaker bar. Getting the car off the ground was the thing that took the longest. Removing the bolt was about 5 min and it was a breeze.

I am convinced that this is the ultimate removal tool for any rounded hex bolt. It is easy and fast to use. Recommended!

Also, the bolts should be fairly tight as they should be torqued to 75Nm with a locking washer.