Whats a good tool or method for removing stripped 8mm allen head from visco clutch? (approx 45nm torque in there)
Tripple square? Torx bit? And what size?
I don't have either of those bit types yet, so I don't want to go and start buying stuff that wont help me.
If it matters the part is off the car.
Thanks.

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html

Help me understand this.

What part is off the car?

__________________
Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"

Half the fan bearing bracket... attached to the pulley and the fan clutch... Fan clutch allen bolt is the striped one...

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html

It sounds as if you took the bearing bracket off with the fan attached.

I can think of no other way to get the fan off w/o 1st removing the 8mm allen head bolt.

I had one of these round off as well as the metal inside is very soft. This happened while I was trying to remove the 8mm from the fan.

SKTOOLS makes what are called pipe plug sockets. The business end is very much like that of an extension, only they come in different sizes. I simply inserted one that fit, then loosened the allen head. The pipe plug socket has 4 corners, so it's going to grip. I'll try to find some photos of them on the SK site and post here. I have never seen these available anywhere else. By that I mean anywhere that the everyday Joe is going to go looking. Snap-On, Mac, etc. might have them.

I tried posting the URL for the specific web page that has a photo of the pipe plug sockets. When you click on the URL below, you'll get to their home page. In the search box in the upper right hand corner, just key in "pipe plug" . Here's the URL to get to the SK siite:


http://www.skhandtool.com/productcatalog.cfm?tok=1

__________________
Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"

Thanks for that link Mike.
Yep ...well the fan blade (3 bolts) was off but the clutch remains attached
the only other way to get it off (aside from unbolting it with the clutch still on) is if the bearing gets shredded...then the only thing holding it on there is the polly V belt- Just take off the belt and it practicaly falls out...

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html

I ended up drilling it and hammering a slightly large (#50) torx head socket in to get a grip and crank out the recessed Allen bolt successfully. Now I just have to get my torx socket back out (eventualy done with a torch, two vise grips and a hammer)

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html

I'm about to do some ignition system work on a 103 motor. It helps to have the fan off and in order to do that the 8mm allen head comes off.

I replaced this bolt some years ago and think I'm going to do it again. I've noticed the metal is very soft and after you had the fan/clutch assembly off 3 or 4 times, it begins to feel like it's starting to round off.

I'm hoping I have one more shot at the existing bolt B4 it gives up.

Mercedes could have done a better job with the composition of this bolt. I have the special Stahlwille 8mm and the locking rod and in spite of this and a lot of slow, careful movement, this piece still has a tendency to round off.

My 2 cents.

__________________
Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"

It does seem that a torx bit or a triple square would be a better choice for a 45nm torque recessed bolt. I did just get a new bolt from the dealer but I wonder if replacing it with one of those other type bits would be practical? At $2.84 for the allen head bolt, that seems to be lower quality finish than the one I removed, it might even be economical. Getting the right sized head would be the problem unless you could get some washers under a smaller head… probably too much trouble but I will keep my eyes open.

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html

It does seem that a torx bit or a triple square would be a better choice for a 45nm torque recessed bolt. I did just get a new bolt from the dealer but I wonder if replacing it with one of those other type bits would be practical? At $2.84 for the allen head bolt, that seems to be lower quality finish than the one I removed, it might even be economical. Getting the right sized head would be the problem unless you could get some washers under a smaller head… probably too much trouble but I will keep my eyes open.
Edit:
P.S. To get the fan off without removing the clutch just take off the three (6mm?) allen bolts that hold it to the clutch. Only 10nm torque and it gives you just about as much room.

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html

I have a snapon kit and its called (10 pieceScrew extractor set)
I have owned it for about 8 years and I remember being suprised at how little it cost when I bought it.

It has payed for its self time and time again.

If I remeber correctly the smallest one even fits in the ignition rotor bolts and thats worth the cost rite there.

The chances are if you get it you will use it again in the future.

It workes even if the recess is totaly rounded out. You just tap it in and the more torque you put to it to remove the bolt the harder it bites in.

GL......................Dave