Stripped bottom vacuum pump bolt...ARRRG
 

OK got the radiator out and all of the bolts out of the vacuum pump except the friggin bottom one. And of course it is stripped.

What have others done in this situation?

Where is my whiskey bottle....???

You can pound a flat head screwdriver into the bolt head and then very precisely turn it without letting go or slipping it, make sure to clean it out first.
Super common problem.

Is there room for something like this - http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=96335 ?

Sixto
87 300D

I've found that Torx sockets work very well in stripped hex heads.

I used vice grips.

irwin extractors work really well

Great idea... great minds think a lot alike... I tired it.. no glory.

I think I will need to get a SMALL pair of vice grips. The pair I have are too big.

I wish I had more room to move around.

I would like to thank the previous owner for being a D.A. in putting the stripped bolt back in the hardest place to get at.

There I feel better.

Neighbors.
 

I'd put the bolts on either side of the stripped one back in, to take the pressure off that bolt.

Good luck!

Jay.

Hmmm good idea. Thinks for the tip.; I will give it a try!

the best idea thus far has been the vice grips. it might be easier if you remove the radiator and evaporator first, or at least undo the couple of bolts for the ps pump and get that out of the way to gain access to the area. tap on the nut a few times with a mallet and then the vice grips should do the job

If you have one use a Propane Tourch to heat the head of the bolt. People are going to say it will expand the bolt but heating it also makes it longer.

Qusiton for someone else: Do those Irwin type External Bolt Extractors really work on Allen Head Bolts?I go mine from Sears but have not had to use them on anything.

yes....


used them one a few rounded upper oil pan bolts...saved me a lot of grief and time

Unless the car has ben retrofitted with a heat pump, the evaporator should not be much of factor. That ranks up there with removing the fuel tank to improve access to the steering wheel.

lol

propane torches are great. minus the spark/flame, you can use them to detect vacuum leaks in the engine compartment

by the way guys, the main reason people strip these bolts is because there's so much grease on the bolts, that the allen wrench will just slip and strip the inside of the bolt. the best bet to prevent this is to use some small screwdriver and some q-tips to remove the grease before going at the bolts with a 4" allen wrench embedded in a socket. tap the socket when the allen wrench is in the bolt hole with a mallet until you're tired of it--always works for me.

careful when you tighten the bolts next to the stripped one. too tight and you'll strip the threads.

While I agree that the Allen Bolt hole needs to be clean I have noticed that all of the Bolts I have removed from my Mercedes have be way tighter than on other Vehicles I have worked on.
While removing the Secondary/Spin-on Fuel Filter housing from a Junk Yard 300SD I snapped in two my Allen Socket. There was nothing in the hole it was just extremely tight.
To remove the 2 Allen Bolts I placed a Punch on the bolt heads of each and a hit the Punch with my Ball Peen Hammer. That loosened them enough to use a regular Allen Wrench on them.
Hitting the head of a Blot to loosen it was a common trick that they used at the LB Naval Ship Yard to loosen rusted and other wise stuck bolts. You just need to be careful not to deform the head.
Unfortunately I did not think to do it before I broke my tool.

Thanks!

I have removed over 100 diesel vacuum pumps from w123 and w126 models, and thus have more experience than you with this particular item. The main reason the bolts strip, is due to grease in the bolt head, not because of over-tightening.

I was not disagreeing with you.

I was implying that there is also other reasons that they can be tighter than expected and I gave an example of what happened to me and a method by which I was able to finish my job.

I have only removed a Mercedes Vacuum Pump one time. While 3 of the Screws gave a good pop when the broke loose I stripped none of them.

In the pic below in my opinion is another reason that some Allen Head type bolt heads get stripped.
The Bit of the tool in the first pic has a lot of radius on the edges and is not flat on the tip reducing the area that makes contact with the Socket in the Allen Head Bolt.
The second pic is one that I have ground down almost flat so that the bit can make full contact in the Socket in the Allen Head Bolt.

That's a darned good idea.

Anti-Seize Compound.
 

A little (teeny, tiny bit) goes a LONG way. Especially when putting a steel fastener into aluminum. I use it on everything that doesn't get loctite. Slows me down a little, but will save whoever does the job next a ton of time!

Jay.

Wow, just slap the guy in the face. I've only removed 6, but only stripped out my first one. Do it once, and you learn.

X2 antiseize

With that wealth of experience, it seems that you would know better than to recommend the removal of the evaporator!!!

lol its ok the guy made an a$$ out of himself in another thread which I cant seem to find but tango found what I was lookin for

You guys are slightly harsh.
Sev is right the Allen Head sockets need to be cleaned out to decrease the chance of stripping them.

I think what happened is that because I quoted him he though it was criticism. And, I did not mean it that way at all.

If I have not made an a$$ out of myself somewhere on the Forum already at some point I no doubt will. I think it is just human.

it's easier to remove with the evaporator out of the way, plus the radiator and the ps pump. but your intelligent comment and the exclamation marks have been noted ;)

i didn't mean to slap anyone in the face--if that's the way i came across then i apologize. it's a fact i've disassembled w123 engines like it's nobody's business, so after a lot of repetitive attempts to remove hard to remove parts, you learn a trick or two that you can pass on.

The evaporator is under the dash board and cannot possibly be a factor when removing the vacuum pump. Maybe you are thinking of the condensor.

yes that's correct, what i meant in my two last posts that mentioned evaporator, was in fact the condensor attached to the radiator. move both of those out of the way. clearly you knew what i was referring to and wanted to try to get the better of me. were you successful?

It was probably just me, sorry. It just seemed to be a little harsh. I do agree, if you've done a bunch, you definitely learn quicker ways to do things.

The truth of the matter is that if you are strong and experienced there are many ways to get the bolt out.
Almost every vac pump has one or more that wont come out right away, main problem is we take out one or tow and think they are all that easy, theres a lot of grease in that area and not every one gets the same level of approach and strenght, in other words they are all a little different to take out.