[86560sel]

Well upon attempting to change the rotor button inside of the distributor cap in my 1993 400SEL, I have discovered that one of them (at least one so far) is stripped out. Apparently I may have done it when using cheap allen wrenches. Other than taking it to a mechanic which I cannot afford to do now, I dont know what to do.

Can I hammer it and break it out so I may be able to then turn the bolt with some pliers? I cant get good enough grip on it now to turn it with pliers. I will then need to figure out how to get just a new bolt for it. I have a replacement rotor button, but no bolt I dont think.

Thanks in advance.

 

[Rupununipete]

Go buy a good quality screw extractor. $20 tops for what you need. Be patient.

There is nothing on that motor that should have a hammer taken to it! Sounds like "Gordo" already got his mitts on your car and made sure it was assembled good and tight.

Let this be a lesson to always use a torque wrench set to proper values when doing re-assembly. Especially into aluminum and mild steel, etc. The small inch value torgue wrenches will pay for themselves the first time you use them, in saved parts and future ease of maintenance.

Good luck buddy!

 

[bayhas]

start the engine and get it to heat up to temp, it helps...

extractor will help, and also, a small hammer and a chisel will help break off the Bakelite rotor and components, to expose more of the bolt head, so you can grab it with a vice and take it off...

 

[86560sel]

Thanks! Yeah, I think Hercules had worked on this car before... supposedly the only people that had ever supposed to have worked on this car is certified Mercedes mechanics.

Anyway after I had posted this, my dad actually told me that he thinks he can get it out. He said he has a screw extractor (which I wasnt aware of, lol) and will take care of it tomorrow. Hopefully all is not doomed yet. Thanks again!

 

[Brett San Diego]

Screw extractor should work easily. I removed two stripped intake manifold allen cap screws from my V12 using a screw extractor. Just tap it in with a hammer to give it a good set in the allen head and back it out.

Brett

 

[nowhereman]

People here are talking about 'allen heads'. All the rotors I've removed have been torx, and an oddball sized one at that. Were you using the correct tool to begin with? Allen wreches will definitely strip a torx head.

If you end up taking a chisel to it, be careful and not bash it. Don't want to damage the shaft bearings.

 

[bayhas]

People here are talking about 'allen heads'. All the rotors I've removed have been torx, and an oddball sized one at that. Were you using the correct tool to begin with? Allen wreches will definitely strip a torx head.

If you end up taking a chisel to it, be careful and not bash it. Don't want to damage the shaft bearings.

Both Bosch and Beru are allen... 5mm for the cap, and 3mm for the rotor to be specific (if memory serves me)

Torx sounds like some aftermarket, or AUS specific market.

 

[bayhas]

BTW, be VERY VERY careful with the use of hammer in there, the rotor mount is made of brittle aluminum alloy, and you can beak it by looking at it the wrong way... focus the hamering with the chisel on the plastic to break it off...

the mount is about 25 dollrs, but is a pain to take off, as it's fastner can strip... that one is bolted into the cam shaft, and is a real pain to drill out...

 

[eric.dewhirst]

Mine was Allen bolt as well and it did appear to be some kind of soft - even copper like - material.

 

[bayhas]

Mine was Allen bolt as well and it did appear to be some kind of soft - even copper like - material.

They are made of soft alloy, and covered with zinc, if they're made of anything harder, they will become impossible to remove, because they are exposed to high temp, and constant temp change, not to mention moisture, and above all, not oiled...

They are fairly easy to strip, particularly if cheap hex keys, or wrong size is used...

 

[Check Codes]

Before drilling and using an extractor, I've had good luck using a dremel and a cutoff wheel to cut a slot across the head, after which you can then use a flat-blade screwdriver to unscrew it. In the event that fails, you can still drill it after.

 

[nowhereman]

Both Bosch and Beru are allen... 5mm for the cap, and 3mm for the rotor to be specific (if memory serves me)

Torx sounds like some aftermarket, or AUS specific market.

Interesting, I see no reason for them being AUS specific so they were probably after market. They were in excellent condition from a '93 400SEL, too good to have been original. The caps were torx as well. The rotor screws were made from a fairly hard metal and I had to buy a bigger set of torx sockets to remove them without damage due to the unusual size.

I have given these to 86560sel to replace his worn ones.

86560sel, you will need to be sure you have the right size torx wrench if you decide to use the caps and rotors I sent you. You should replace them as a pair as MB changed the design, the caps I gave you may not be compatible with the existing rotors. This is especially true if they are aftermarket.

 

[mrtalkradio]

Before drilling and using an extractor, I've had good luck using a dremel and a cutoff wheel to cut a slot across the head, after which you can then use a flat-blade screwdriver to unscrew it.

Bingo. That's what I did, worked perfectly. Remove the plastic housing covers though so you can get to it.

 

[86560sel]

Thanks for all of the replies and tips!

Well, being as impatient as I am, I got tired of waiting on my dad (I didn't even know where his tool kit was and he was at the VA most of the day), so I just decided to pass on replacing the caps/rotors for now and put it all back together. I started the car and it is purring like a kitten again. My main issue was the non-starting problem, so I am hoping that the replacement EZL that Trevor (tlampre) sent me takes care of the hot non-starting issue. I let the car run today until it got to full operating temperature (up to 80°c on the gauge) and it restarted everytime, but I know the the engine actually gets hotter after it is driven. It was getting too close to dark for me to venture off in it incase it did conk out.

I was going to go ahead and replace those caps and rotors because when I started the car the other day even after the replacement EZL, the car was kinda missing and sputtering, but it could have been where it has been setting and not driven much at all over the past several months. When I started it this evening, it did that initially, but it cleared out and was running very quietly and smoothly and did for the 20 minutes I let it set there and run.

Funny thing about those bolts... the ones on my caps are actually "hex" heads, as well as the ones on the caps. One of the hex bits I had worked perfectly in the cap bolts, but on the rotor button, the one I used was too small, which is why it stripped out I think, but the next size up was too big. Like you said, it probably will take me getting that $65 set and I guess something I need to keep in mind in the future for when I really need to change these out. For now though, I think my caps/rotors are ok, but I am keeping these extras for future use. I tried using a torx bit kit on the rotor button bolts and none of them would even come close to working. I guess sometimes these old W140s need special tools that this old fella don't own. lol.

Thanks again for all of the help and to tlampre for the parts!! I will get this car back on the road yet!!

Interesting, I see no reason for them being AUS specific so they were probably after market. They were in excellent condition from a '93 400SEL, too good to have been original. The caps were torx as well. The rotor screws were made from a fairly hard metal and I had to buy a bigger set of torx sockets to remove them without damage due to the unusual size.

I have given these to 86560sel to replace his worn ones.

86560sel, you will need to be sure you have the right size torx wrench if you decide to use the caps and rotors I sent you. You should replace them as a pair as MB changed the design, the caps I gave you may not be compatible with the existing rotors. This is especially true if they are aftermarket.