How to extract stripped Allen bolt? - PeachParts Mercedes-Benz Forum

vegburner · #1 02-06-2006, 11:37 PM

How does one extract a stripped torque converter (Allen) bolt? I turned the inside part where the hex wrench is supposed to grip. Now what do I do?

Thanks for all replies!

Randy

lietuviai · #2 02-06-2006, 11:52 PM

Try locking pliers.

Nate · #3 02-06-2006, 11:57 PM

put the allen wrench into the stripped bolt, and put some sideways pressure on it... If its not stripped too bad, it will grab on whatevers left.

Whats the condition of the hole?

Other options are: moving to a SAE size thats bigger then the metric you stripped it with, and putting it into the freezer to make is contract. Then force it in.
You cold JB weld the wrench into it, letting it sit 24 hours, and try again

drill with lefthanded bit
eazy out

the condition of the hole is the bigger consern, whats it like?
~Nate

H2O2 · #4 02-06-2006, 11:59 PM

I've had good luck hammering an XZN socket of the same size into the stripped Allen bolt, then turning it out--it's never failed me yet.

sailor15015 · #5 02-07-2006, 12:04 AM

The rear rotors on my bimmer are held on with a small 5mm allen head bolt and of course they both stripped smooth on the first turn. I got the Craftsman Easy-Out and that worked. I think the trick with those is to use a 120v drill, the plug-in kind, not the portable variety. It wouldn't come out with a portable drill but the extra torque from the plug in drill took the bolt right out.

Strife · #6 02-07-2006, 12:12 AM

This may seem like a smart-a** answer, but try to avoid it happening in the first place. First, apply liquid wrench (and wait 30+ minutes) to things you know are going to be bad (external exposure) and where practical (subframe mounts, etc). Second, use brake cleaner or a similar hose nozzle cleaner to entirely remove all grime from the inside of the bolt head first, so that you can get all the way down and maximize the surface area of tool to bolt.

AFTER a problem develops, I've used TORX tools with some success.

airbus · #7 02-07-2006, 12:35 AM

Do what H2O2 said. It works.
BTW: H2O2, your Ladeluftkuehler is damn cool! How many Pferdestaerken has it now?

rs899 · #8 02-07-2006, 06:58 AM

Another approach if you have enough access to it is to take a hammer and chisel and whack it in the proper direction.

H2O2 · #9 02-07-2006, 03:15 PM

Quote:

Originally Posted by airbus

Do what H2O2 said. It works.
BTW: How many Pferdestaerken has it now?

Edumacated guesstimates put it at ~180hp

imdavid28 · #10 02-07-2006, 04:08 PM

Quote:

Originally Posted by rs899

Another approach if you have enough access to it is to take a hammer and chisel and whack it in the proper direction.

Just did that the other day to seprate my crank pulley from my dampner. Went real smooth.

kip Foss · #11 02-07-2006, 05:23 PM

If you can get a good shot at it with a hammer hit the plug a few good solid blows with a 1 pound hammer. Not just a few bangs but really hard dead center raps. The shock will often loosen the plug. Don't use a brass drift since the softness of the brass will defeat the shock you want.

If that doesn't work heat the plug with an oxy torch until it is near red and then let it cool. This will cause the plug to shrink slightly and it could come out.

If you know how to weld you can weld the allen wrench to the plug. Quench the hot weld and then heat it to a blue color to temper it. This process sounds more complicated that it is.

I would not try a drill and easy out. Allen bolts and plugs are extreemly hard and I would venture to say that you will, at best, dull the drill and at worst probably break it off before you make much head way.

thatguy · #12 02-07-2006, 05:38 PM

http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=SEARS&sid=I0008300030000100085&pid=00952160000

This is what I used to extract a rounded hex bolt that was wedged up against the body of the car holding in the old tranny modulator. Putting a lot of penetrating oil on the day before and letting it sit also helped a lot.

Nate · #13 02-07-2006, 05:46 PM

Quote:

Originally Posted by kip Foss

If that doesn't work heat the plug with an oxy torch until it is near red and then let it cool. This will cause the plug to shrink slightly and it could come out.

Unless im missing something, your saying heating up a plug will make it shrink??? Metal expands when hot, and this is on a torque converter... That cant be good for anything...

Am I missing something?

~Nate

MS Fowler · #14 02-07-2006, 08:40 PM

On an allen that holds the motor mounts on my 300SD, I welded on size smaller allen wrench into the socket. It was tough, but it worked.

kip Foss · #15 02-07-2006, 09:45 PM

Nate,

Read my post. What did I say after I said to heat the plug red hot? I said to cool it quickly. It is the cooling part that makes the bolt shrink. It doesn't shrink by much but I have seen, in my 50+ years of doing this, many a bolt that after heating and cooling can be loosened by hand.

There are many many ways of removing frozen nuts and bolts. Try what seems reasonable to you and what you have the tools and skills to do. Over the years you will come to recognize certain senarios that call for certain methods. Remember them and pass them along to others when it comes time.