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1982 380SE AMG euro(parted out),1983 300SD "Good Girl", 1984 500SEL AMG euro "Bad Girl"
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3,256 Posts
Discussion Starter · #1 ·
Hey Guys!

Long time no see. I've had some crazy stuff and schedule to maintain. I haven't even been able to log on and see what's been going on. I've got just a few days before I need to get the 82 380se out of the hanger. While I was gone the airplane came back after a new engine with major mods and my client was able to shoe horn it in there with the car too. Unfortunely our first flight was about three minutes long due to soaring temps when we reduced take off power so the aircraft went back to the mechanic.

Here's my problem. I want to get the cams out for a forum member but I've got THREE stripped bolts on the cam towers. I've tried drilling through the head of the bolt with Ti bits and I'm getting nowhere. Anyone got a link to a magic extractor for these f'ing things? I've only got a few hours left to put into this otherwise I've got to throw in the towel :(
 

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w126
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1,535 Posts
You might be able to weld a bit into the stripped bolt. Epoxy or something like that takes time to cure.
 

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CH4S Admin , Outstanding Contributor
1985 500SEC, 1991 190E 2.6.
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43,793 Posts
Hammering in high quality torx bits might work, or try to drill a small (and straight) hole and use a counter clock wise threaded conical 'easy out.' Both need to be of good quality though.
There are newer types of 'easy outs' on the market, the experts here might know more (Jonathan?). He mentioned a 'freeze off' product.
Cheers

P.S. I have come across head bolts, some moron had cranked on with an air impact gun, with the result of rounding off the hex openings, which made them un usable for the next guy, and blue loctite.
Talk about a PIA.
 

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1982 380SE AMG euro(parted out),1983 300SD "Good Girl", 1984 500SEL AMG euro "Bad Girl"
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3,256 Posts
Discussion Starter · #6 ·
Hammering in high quality torx bits might work, or try to drill a small (and straight) hole and use a counter clock wise threaded conical 'easy out.' Both need to be of good quality though.
There are newer types of 'easy outs' on the market, the experts here might know more (Jonathan?). He mentioned a 'freeze off' product.
Cheers

P.S. I have come across head bolts, some moron had cranked on with an air impact gun, with the result of rounding off the hex openings, which made them un usable for the next guy, and blue loctite.
Talk about a PIA.
I've heard of freezing your nuts off but this is a different animal with the threads hidden 3" away :) I've thought about trying to sacrifice some 8mm hex key and using my mig or welding a bolt. Thing is, I don't have too much time to mess with it at this point. Has anyone tried this style of extractor?
eBay Motors: Snap-on Bolt Extractor Set 13 Pcs Blue Point Stad/Mectr (item 200221188272 end time May-05-08 19:22:07 PDT)
 

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'86 E300 Diesel '82 300 SD '87 560 SEL
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432 Posts
The Snap-On extractor worked every time for me. The conical easy-out some times likes to break and it's so fun to drill them out.
 

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91 560 SEL
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244 Posts
I had one allen bolt stripped from the cam tower the other day - the smaller one, on a 560sel. I used "Bolt Out" from Sears. It worked like a charm.
 

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1982 380SE AMG euro(parted out),1983 300SD "Good Girl", 1984 500SEL AMG euro "Bad Girl"
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3,256 Posts
Discussion Starter · #9 ·
The Snap-On extractor worked every time for me. The conical easy-out some times likes to break and it's so fun to drill them out.
I agree! Those are the last thing I'd want to use. I think I'm 49% success with them.
 

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1987 420SEL
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1,133 Posts
These bolts are made out of a very resilient steel alloy which makes drilling them out with regular carbon steel or high-speed steel drill bits nearly impossible. I had to drill several of mine out using carbide drills. Not "carbide-tipped" drills, but solid, one-piece pure carbide drill bits. I used 0.125"-0.375" diametres in steps to effectively drill a pilot hole, then progressively larger holes until the capscrew head was drilled off. It should be noted that these holes are ONLY to the depth of the hex key slot.

Bolts in general are secured in place for two reasons: the friction caused by tension between the threads of the shank and the hole (10%) and the friction between the underside of the bolt head and the surface it mates against (90%). Removing the entire bolt head and thereby the major surfaces under the most frictional force relieves tension on the threads as well. Now you can drill the remaining shank of the bolt out with something like a 3/16" drill (perhaps smaller to allow more material to be gripped) and hammer in a wedge-type exractor.

The down side to this method is that carbide drills are nearly $30 for a single 3/8 drill, and the heads have to come off if the threads have cold-welded themselves in thier bores, because now you've effectively removed any means of grasping the shank of the bolt.

I've also had success shearing off the heads of the capscrews with a VERY sharp flat chisel. This only works on the bolts which are 90 degrees to the head and have washers underneath them, because the washer will take the majority of the abuse rather than the cam tower itself. I'm also re-threading all the headbolt holes on my car too though, so the potential to destroy the threads in the block isn't a concern of mine.

I agree with trying some sort of readily available nut extractor before trying my 'last ditch' methods.
 

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2009 SL65, 1998 CL600 (sold), 1989 560SEL (sold)
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403 Posts
I had to drill the head off of a cam tower bolt when I did the heads on my 560SEL. I don't remember it being very difficult. Remember that when drilling metal use a slow speed drill and add some cutting oil (I use rapid tap). If you drill too fast the heat will dull the bit in just a few seconds. I used cobolt tipped (~$5) drill bits.

Put a rag around the bolt to catch the shavings, then vacuum everything afterwards.
-Dave
 

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1987 420SEL
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1,133 Posts
I was thinking about this again today, and one thing that can make a considerable difference when you go to drill the bolts out is centre-punching them first. This allows the cutting edges of the drill to 'bite' very effectively and drill through the metal rather than burning out by rubbing against it.

Just put a centre punch in the middle of the bolt socket and give it a good hit with a hammer; if you choose to drill them out, it will help greatly.
 
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