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1996 SL500 Sport, 1992 SL500 (sold)
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117 Posts
Discussion Starter #1
Was doing a transmission service and bought a new T30 socket from AutoZone to remove the bolts and as you can see from the attached, it didn't go well. I was using a 3/8 ratchet so didn't think I had enough torque to snap it. Any thoughts on how to proceed?

My first thoughts were to drill out the center and use small chisel to cut out the remainder but I wanted some advice before proceeding. In hindsight, I guess I should have heated the bolts but the first two broke loose with moderate torque.
T30.png
 

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1998 SL500, 1999 ML320
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129 Posts
I am not in favor of drilling anything in that area. There are some very good solvents that have worked for me, but may not be available locally. I bought something like "Knock her Loose" on Amazon and it solved several problems. If you do decide to drill, be sure you have a selection of those tapered-reverse screw extractors. In any case it's a bit hard to see the situation in the picture. Is the head of the bolt available to grab from the outside? I would go for mild heat after a solvent-release treatment. YouTube is full of "heroic" removal of stuck bolts and I doubt you want to do that while working under a car.
 

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1992 Mercedes 300SL R129. 94 S320 Mercedes w140
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61 Posts
See if you can get a slide hammer into the hollow in the broken tool. Pull out the broken part and try some lube like previously suggested. Then buy a good tool and try again. Let the lube sit overnight and reapply before trying again.

you might be able to use a pair of small vice grips to help too.

Try to tighten the bolt just a bit before you try to loosen it.. that will brake the static tension before you try to loosen it.
 

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1996 SL500 Sport, 1992 SL500 (sold)
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117 Posts
Discussion Starter #4
I am not in favor of drilling anything in that area. There are some very good solvents that have worked for me, but may not be available locally. I bought something like "Knock her Loose" on Amazon and it solved several problems. If you do decide to drill, be sure you have a selection of those tapered-reverse screw extractors. In any case it's a bit hard to see the situation in the picture. Is the head of the bolt available to grab from the outside? I would go for mild heat after a solvent-release treatment. YouTube is full of "heroic" removal of stuck bolts and I doubt you want to do that while working under a car.
I like your easy-out idea for removing the Torx bit. The bit is hollow, so I should get some good bite with the extractor and be able to wiggle the bit out. I'll definitely try the solvent and heat on the pan bolt. Thanks for your help.
 

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1998 SL500, 1999 ML320
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129 Posts
See if you can get a slide hammer into the hollow in the broken tool. Pull out the broken part and try some lube like previously suggested. Then buy a good tool and try again. Let the lube sit overnight and reapply before trying again.

you might be able to use a pair of small vice grips to help too.

Try to tighten the bolt just a bit before you try to loosen it.. that will brake the static tension before you try to loosen it.
I had long ago forgotten the notion of doing a test tighten on a stuck bolt. It actually works.
 

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1996 SL500 Sport, 1992 SL500 (sold)
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117 Posts
Discussion Starter #6
Good idea on the test tighten. I'll try it too. Any suggestions on a good T30 socket? I'm reading that they all will break and that the Snap On Gold were supposedly the best.
 

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1998 SL500, 1999 ML320
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129 Posts
I apologize. I didn't see that the driver was broken down inside the bold. Isn't there enough space on the outside to attack it with a channel-lock? I think someone suggested that. About drilling and chiseling, my notion is to not remove anything that can be useful to grab onto at some point.

Also, thinking of screw extractors, I looked at mine and they all need a deep hole to get a grip. I also found I had some extractors that are designed to work, right on the surface, of slotted and Phillips screws but none of a size that handle that bolt. Chances are that by now you have solved your problem.
 

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1996 SL500 Sport, 1992 SL500 (sold)
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117 Posts
Discussion Starter #8
I apologize. I didn't see that the driver was broken down inside the bold. Isn't there enough space on the outside to attack it with a channel-lock? I think someone suggested that. About drilling and chiseling, my notion is to not remove anything that can be useful to grab onto at some point.

Also, thinking of screw extractors, I looked at mine and they all need a deep hole to get a grip. I also found I had some extractors that are designed to work, right on the surface, of slotted and Phillips screws but none of a size that handle that bolt. Chances are that by now you have solved your problem.
No worries. You got me thinking on the right track to remove the bolt once I got the T30 bit out of it. Since the T30 was hollow, I was able to get a pick inside of it and grab the bottom edge and pull it out with a magnet.

I've got some Liquid Wrench on all the bolts right now and ordered the Knock her Loose technical strength that you suggested should I still have issues. I'm going let it soak overnight and give her a go tomorrow. I think I'll try and heat it, tighten it a little first like LewisMend suggested and see if I can break it loose. Thanks for the help.
 

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'91 560SEC, '98 SL500
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None of that liquid penetrant will work or drilling the head....none. I've been doing this for decades now and dealing with rusty old cars longer than I can remember.

The ONLY way to get that bolt out is:
1) Hit the bolt with MAP gas, get it nice and hot.
2) Hammer this Irwin extractor over the head of the bolt, and use an impact to back it out. The hammer action of the impact will break it free combined with heat you just applied. These Irwin extractor tighten as they back out (similar to a "Chinese Finger"), so will not slip on the head of the bolt.
 

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1996 SL500 Sport, 1992 SL500 (sold)
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Discussion Starter #10
None of that liquid penetrant will work or drilling the head....none. I've been doing this for decades now and dealing with rusty old cars longer than I can remember.

The ONLY way to get that bolt out is:
1) Hit the bolt with MAP gas, get it nice and hot.
2) Hammer this Irwin extractor over the head of the bolt, and use an impact to back it out. The hammer action of the impact will break it free combined with heat you just applied. These Irwin extractor tighten as they back out (similar to a "Chinese Finger"), so will not slip on the head of the bolt.
Thanks for your input. I think I'm at a good point as I haven't damaged anything and could really use your guidance. I've removed the broken torx bit from the bolt, so I've got a clean bolt head now, no rust. I soaked it with Liquid Wrench overnight but the bolt goes through a spacer into the tranny, so even though I've soaked all around the base of the spacer, it's much wider than the bolt so I question if the oil is reaching the threads.

I heated the bolt and spacer with a hand-hold butane torch that I see only hits 2500 F and couldn't break the bolt loose. I'd like to make one last attempt before scrapping the filter change on the tranny and bringing it to a shop with the right equipment. Your thoughts?
 

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1996 SL500 Sport, 1992 SL500 (sold)
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117 Posts
Discussion Starter #11
Finally got it. Got an impact screwdriver from Harbor Freight and gave it a whack with a 3lb dead weight hammer several times, then put the Craftsman T30 torx socket that I bought, which was solid and not hollow like the one that broke, and gave it a yank on a breaker bar. Thanks for all the help.
 

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93 SL500, 95 SL320, 96 S320, 98 S500, 2002 E320 4Matic Wagon & A little 91 5.0 FORD Mustang
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8,064 Posts
Hey J,

Do not use those "security Torx" bits(with a hole in the center) They will all do that. Do the Irwin extractor, or go for the standard of cutting a slot with a Dremil tool and a cutting wheel, so you can use a flat screw driver... I too would recommend the gas, but do not know how oily you car, I would not recommend it first...

All the best with that bolt..

Martin
 

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1998 Pano SL500; 1993 SL500; 2005 ML270cdi
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8,841 Posts
I would imagine that the pan has been removed before and the torx bolts over tightened beyond I think 18 Nm.to snap that torx socket

I had the same problem with my Rexton that has the same gearbox, however using a large pair of grips I loosened the stuck bolt.
Rightly or wrongly I replaced the bolts with a smear of copper grease and tweaked the torque spanner to 19Nm.
 

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1996 SL500 Sport, 1992 SL500 (sold)
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117 Posts
Discussion Starter #15
I would imagine that the pan has been removed before and the torx bolts over tightened beyond I think 18 Nm.to snap that torx socket

I had the same problem with my Rexton that has the same gearbox, however using a large pair of grips I loosened the stuck bolt.
Rightly or wrongly I replaced the bolts with a smear of copper grease and tweaked the torque spanner to 19Nm.
Good to know about the grease. I may give it a shot in case I need to get in there again soon.
 
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