Old Automobile Needs Assist

[Tobago]

This may the incorrect place to post this request but the old car is built like an anvil, slightly more complex but solid. this is a problen of moving old siezed metal.

My older son has a 1984 Mercedes 300D. It's not a collector car or anything, just an old diesel that he enjoys. Six years older than him in fact but that's neither here nor there.

Anyway it turn out the car needs a new differential. They seem to have a genetic problem with elongating the hole the carrier axle runs through.

He located a repacement differential in a salvage yard (junk yards are no more, takes the adventure and romance out of fixing an old machine) but the crew there breaks a stud on the hanger.

The assist he needs is how to free up one or mor studs in the original diff and how to get the broken stud out of the replacement.

The diff body casing seem to be cast aluminium with steel studs galled in there.

Any recommendations will be appreciated. Thank you all.

Excelsior,
Ted

[David Einhorn]

Old cars have good usable parts for blacksmithing:

- leaf springs and coil springs can be made into blacksmithing tools, if you heat up the coil springs you can straighten them as they are useful for making punches and other tools.

- axles of old cars are also useful for making tooling.

- the fenders and other sheet metal can be cut up and forged into decorative items such as flowers or used in reposea work.

- people have also used car motors in making "junk yard hammers"

Hope that helps, :D

[Nakedanvil - Grant Sarver]

Kinda like when McCain was asked if he wore boxers or briefs. He said, "Depends". In this case it depends on if the stud is broken off flush, below flush, or above. Most of the studs can be removed by using two nuts and jamming them together to turn the stud, sometimes need to keep two wrenches on. Often you need to apply some heat to the stud, a little propane torch will do. Heat for a good minute and try it while hot, otherwise let it cool completely before trying to remove. If the broken one has anything sticking up you might get pipe wrench or vise-grip on it after heating. If broken off flush, you need put an oversize nut over it and plug weld the two together. Turn the welder way up. Below flush? You're S.O.L. If that's the case, come back and we'll have a few more ideas.

Oh yeah, some good penetrating oil can help too.

[Rob Browne]

Just be a bit careful of the housing if you are gong down the heat road. Aluminium is hot short, it breaks up really easily when hot so take it gently.

[Dragons lair]

Grant, I was beginning to think I was the only one removing studs by welding a nut on.
Actually i prefer 1in flatbar as long as possible. drill one end weld then tap other with a hammer. Locals here are amazed.
Ken

[Nakedanvil - Grant Sarver]

Dragon: Oh yeah, sometimes I just weld the end of a flt bar to it, what ever works. The heat from welding helps the whole process.

[jeremy k]

I have drilled a hole down the center of the broken bolt also and tig welding the hole up - when the weld cools it will shrink the bolt in size just enough after it's cooled off it will back out if it's grabable or like the others have said weld something onto it also. Another way is (if you have aluminum capabilities) is just grind out the side of the bolt hole area and remove the bolt and re-build up that area - drill and tap for a new bolt -JK

[HWooldridge]

Dragon: Oh yeah, sometimes I just weld the end of a flt bar to it, what ever works. The heat from welding helps the whole process.

It's called a redneck EZ-out down here. I've pulled many stuck bolts by welding a nut or bar onto a busted stud - works like a champ.

[arftist]

There are several ways to attack this problem, but let me preface by saying that nothing grabs a steel stud as tightly as aluminum. Asuming that the studds are flush or below the surface, Grant's method of welding a nut to the stud is most likely to work. The key to this method though, is to allow everything to completely cool before atempting to turn the nut. To do otherwise is to garantee that the weld will break or the studd will break off a little below the weld.
If the studd is broken below the suface, all is not lost. A very special (and expensive rod), MG600 can be used. The flux coating of this rod will flow out and fill the thread area, forcing the bead to build up in the shape of a pillar. Idealy one would orient the work so that one could comfortably strike and maintain an arc right in the center of the studd from staight above, continuing to feed the rod until the pillar is high enough above the surrounding surface to easily weld to a nut. Again, it is essential the the work cools fully before atempting the stud removal.
Another method is to carefully centerpunch the center of the stud, drill as large a hole as possible, and remove the stud with an EZout type of tool. It is also possible to drill most of the stud out, leaving just a shell or tube, just inside the threads, which can then be collapsed with a cold chisel or a cape chisel. In using both of these methods, great care must be taken to center the centerpunch on the stud. If it sticks up a little, and is broken unevenly, grind it flat.
If the threads are damaged in the process, they can be repaired by use of a thread insert such as a heli-coil or a time-sert, or in severe cases, welded up, and redrilled and tapped.
The final method of stud removal would be EDM or electrical Discharge Machining. You may have to call around to find a shop capable.

[Nakedanvil - Grant Sarver]

I can't even spell EDM!

[ptree]

In many cases, studs are factory set with loctite. The stud is treated with Loctites stud setting compound, used to be the 277. It is red and is PERMANENT. The only way to pull a steel stud from an aluminum case once Loctite 277 has been applied is to apply heat. Takes about 345F to melt the polymerized loctite, and allow the stud to be twisted out.

[welder19]

There are several ways to remove broken bolts but with out knowing ho it's broke it is imposible to tell you the best way to do it, a pic would be best.

welder19

[BIGGUNDOCTOR]

With this project it can go from being a snap to becoming a snafu really fast. Especially if you do not have the correct tools available. How much would a local shop charge to remove it? May be cheaper for you in the long run.

[Yance]

Grant, I was beginning to think I was the only one removing studs by welding a nut on.
Actually i prefer 1in flatbar as long as possible. drill one end weld then tap other with a hammer. Locals here are amazed.
Ken

Yep, some of us are easily amazed, but we can learn new tricks. Thanks for the flatbar tip.

[Tobago]

Thank you all.

Son got it out and a replacement from the old diff. there was enough to get a bit on with vise grips after a good soak with liquid wrench and claping to the bench for a good solid purchase. Getting an unbroken stud out of the old differential was a bit more of a challenge. Very tight. Soaking with liquid wrench, and judicious rap with ball peen before torguing on a couple of jammed nuts got it.

I believe it came down to more patience than brute force as the penetrating oil got in there.

Thanks again.

Excelsior,
Ted