Can't remove transmission modulator; I give up - PeachParts Mercedes-Benz Forum

lonewolftek · #1 02-24-2009, 04:30 PM

Of the two Allen head bolts holding the trans modulator in place on my '83 300SD, one seems to be quite stripped out. I can't get any tools in there other than the Allen wrench. I don't feel like dropping out the entire transmission to fix this.

I think this is the last straw. I'm going to throw in the towel and just put both of my 300SDs on Craigslist.

DeliveryValve · #2 02-24-2009, 04:43 PM

Have you tried just dropping the tail of the tranny by unbolting the four screws on the rear mount? And if still don't have clearance, you might have to unbolt the driveshaft shield and center support bearing to the get more clearance.

Then you can use a tool like "bolt out" to move the stripped bolt.

JonL · #3 02-24-2009, 04:56 PM

can you take out the driveshaft and trans mount and let it hang down a bit to get more access?

JonL · #4 02-24-2009, 04:57 PM

Oops. DV beat me to it.

E150GT · #5 02-24-2009, 04:57 PM

I had this problem. I ended up taking it to my indy. Best 100 dollars I spent. I was so frustrated I threw my cell phone on the ground.

pawoSD · #6 02-24-2009, 04:59 PM

Quote:

Originally Posted by lonewolftek

Of the two Allen head bolts holding the trans modulator in place on my '83 300SD, one seems to be quite stripped out. I can't get any tools in there other than the Allen wrench. I don't feel like dropping out the entire transmission to fix this.

I think this is the last straw. I'm going to throw in the towel and just put both of my 300SDs on Craigslist.

Tried vice grips? I replaced it on my SD and it took like 15 mins....

I don't think I'd sell the whole car because a bolt was hard to get off.....maybe I just have a bigger supply of straws.

JonL · #7 02-24-2009, 05:04 PM

With a small screw like those, sometimes you can also use a small cold chisel and hammer. Don't try to chisel off the head... apply the chisel kind of tangentially to the face or side of the head so as to start it unscrewing. It's really very effective, even if it is awfully crude. Replace the screw when you are done to hide the evidence of your butchery.

pawoSD · #8 02-24-2009, 05:12 PM

They're not in there that tight, so that would probably work pretty well.

automch · #9 02-24-2009, 05:26 PM

I have worked on a lot of Benz allen head bolts over the years and have found that if you can hit the head flat on with a punch to slightly mushroom the head, it will also reduce the inside hex. Then drive the allen socket or bit into the bolt until it bottoms. The combined impact of the hammer action to flatten out the head, and driving the bit into it, not only give a new tight fit but also may also serve to loosen it some so it will now come out. Then just put a new bolt in in place of it. HTH

pawoSD · #10 02-24-2009, 05:40 PM

Quote:

Originally Posted by automch

I have worked on a lot of Benz allen head bolts over the years and have found that if you can hit the head flat on with a punch to slightly mushroom the head, it will also reduce the inside hex. Then drive the allen socket or bit into the bolt until it bottoms. The combined impact of the hammer action to flatten out the head, and driving the bit into it, not only give a new tight fit but also may also serve to loosen it some so it will now come out. Then just put a new bolt in in place of it. HTH

I don't think that'd be a very good idea on the side of the transmission.

lonewolftek · #11 02-24-2009, 07:51 PM

Thanks all for the suggestions. I may have another go at it tomorrow. Right now I'm tired and frustrated and covered in grime. It's just been one thing after another.

JonL · #12 02-24-2009, 08:12 PM

I'm sure many of us know the feeling. Not that it's any consolation. I'm sure you will prevail!

John Schroader · #13 02-25-2009, 10:17 AM

This brings back unpleasant memories. Replacing the trans modulator was one of the very first repairs I made on my 300 D. Stripped the hex head right off the bat. I was advised on this forum that lowering the transmission would not give me the desired access. Later was advised that indeed it would. At any rate, I used a hole saw and made a 1 1/4" hole in the tunnel, allowing good access to the stripped bolt. Used an EZ out and then patched the tunnel. Good to go.