Imagine my surprise when removing rear brakes

[CJHenderson]

When I removed the disk brake and rotor to find that there is a drum brake system that is used as the emergency brakes. Being this is the first time restoring and working on the Mercedes and then Imagine my surprise when finding that setup. To say that I was shocked is a total understatement. Well I guess that I should expect other things on the Pagoda that will surprise me

[jameshoward]

 

How did you think the handbrake worked (never understood why Americans call it the 'emergency bake')? (Maybe because if you pulled on it whilst driving one really would find oneself in an emergency situation). The Merc is no different to any other modern car with discs that also serve as a handbrake using shoes on drums inside the disc. 

Good luck with the work. Plenty of helpful rear axle and brake posts on the site.

[Shvegel]

Fairy common on European cars.  There are a few that use special calipers that have mechanical actuators but they are rare.  If you have to remove the springs that run from one shoe to the other a good pair of needle nose vice grips works really well.  I have the factory tool and I think the vice grips work better.

James,
The thinking here in the colonies is that if you refer to it as an emergency brake you will be more likely to remember to use it in an emergency.  Of course we generally don't use them for parking over here and are lacking the strict MOT inspections you have so many of the "Emergency" brakes here end up being inoperable.

[Howard Long]

I think that the death of the "hand brake" is clearly connected with the obvious desire by American auto makers to eliminate the manual transmission on new cars back in the 60"s and 70"s.  When they moved the "additional manual brake" from a handle to a foot pedal, it was no longer of any use with a manual transmission.  I think that is when the "additional manual brake" became known as the "Emergency Brake" to some but was known as the "Parking Brake" by most Americans.   To even consider using that funny petal in an "Emergency" is unlikely in that most of us did not even use that funny petal for parking or at any other time. That is also why many Parking Brakes are not maintained, no one even knows they are there.

However, for those of us "old guys" that have stayed with manual transmission autos all our lives, that funny pedal in front of the driver's door was really useless.  You could not possibly use the clutch and the parking brake at the same time.  If you have driven an American manual transmission car without a hand brake in a hilly city like Atlanta, it takes really good foot work to stop at a traffic light going up hill and then start again up the hill.  My son's 67 Mustang was like that and my wife needed to go somewhere and got stymied on a hill in the Mustang.  Finally a nice gentleman that was stopped behind her, came up and drove the Mustang up the hill and thru the light and let my wife get home.  She never drove the Mustang again!!!

After driving manual transmissions for nearly 60 years, I finally had to go to a automatic, my left leg just could not do the clutch any more with traffic in a busy city.  However I did not go to just any car.  I got a bright red BMW 335I convertible with paddle shifters as my driver until my 280SL is back on the road.  I will go back to the clutch then.

Howard
71 280SL 4-speed

[mdsalemi]

It's really quite simple why this device was/is called the "emergency brake"; it is because the actuation mechanism is completely independent of any other system (such as the hydraulics) that controlled the normal braking. Thus, it could be used in an emergency situation when the hydraulic brakes failed...something once all too common.

Remember in the 1950s and into the 60s for many low-end cars, there was a single-system hydraulic unit that controlled the brakes. One failure of any kind, and you have no brakes at all. Enter the dual-braking circuit, with independent hydraulics such as if one failed the other still worked.

I remember quite clearly, going down a hill at night on the E8 autobahn approaching Pforzheim, Germany as a teen in 1971. I was riding shotgun in the front with my uncle driving. As he began to brake and downshift, he realized that the [single braking hydraulic system] on the Ford Taunus we were in failed. Luckily, his skills as a driver came into play, and he gently grabbed the emergency brake, and by using that and downshifting, we were able to come to a safe stop. The car was towed to the local Ford dealer and brakes repaired the following morning. The culprit? a rusty brake line burst.

[Shvegel]

CJ,
I understand you are pulling the axle assemblies for restoration.  be careful not to bend the brake backing plates if you set them on the ground.  My body man dropped the axles out on the floor and bent the plates all up.  I straightened them out but was unhappy with the front ones so I thought "I will just order new ones for some ridiculous amount of money and be done with it."  Well,  what I thought would be ridiculous like $130 each turned out to actually be $700 for one side and $900 for the other!  Needless to say I went back in the garage and spent more time with the hammer.

[CJHenderson]

CJ,
I understand you are pulling the axle assemblies for restoration.  be careful not to bend the brake backing plates if you set them on the ground.  My body man dropped the axles out on the floor and bent the plates all up.  I straightened them out but was unhappy with the front one so I thought "I will just order new ones for some ridiculous amount of money and be done with it."  Well,  what I thought would be ridiculous like $130 each turned out to actually be $700 for one side and $900 for the other!  Needless to say I went back in the garage and spent more time with the hammer.

Thanks for letting me know I'll be careful with that. What I plan to do is to remove the rotors and back plate to make it easier for me to get the sub frame and rear down.

[Shvegel]

Stands help a lot.  I knocked 6" off the front stand after I took the photo.

[jameshoward]

It's really quite simple why this device was/is called the "emergency brake"; it is because the actuation mechanism is completely independent of any other system (such as the hydraulics) that controlled the normal braking. Thus, it could be used in an emergency situation when the hydraulic brakes failed...something once all too common

My dear Michael, what utter nonsense.

Try parking a car on a slope with no parking brake. The parking brake (probably the correct term) is cable actuated because the cost of providing a system that could use the hydraulic means would be most expensive. The fact that your friend used the parking brake to stop a car is unrelated and is an additional benefit. I've used a stone wall for similar purposes; not what the wall was designed for, but it slowed the car. So to suggest the hand/ parking brake is there for emergencies because it's separate from the hydraulic system is rubbish. Your thinking perhaps reflects the US experience solely, which is automatic transmission focussed. The rest of the world, and admittedly I refer narrowly to the UK and Europe, tended more towards manual transmissions largely due to factors like less space, less money, the cost of oil and if one lives in Wales, Scotland, Switzerland, the Alps, the Dolomites, and so on, more hills. One needs a handbrake!

I now look forward to the production of empirical evidence from manufacturers that will prove me to be utterly incorrect.

Incidentally, our tanks have hydraulic and transmission braking. They also have cable actuated brakes to hold the vehicle on slopes when the vehicle is stopped/ engine off. Just don't try stopping a 70 ton vehicle with a parking brake. Or a stone wall. Another tank, though, works quite well as a buffer if an expensive one.

JH

[Shvegel]

James,
What a coincidence.  I once used my W113 and a stone wall as a means of stress reduction.  Of course back then it was a much less expensive endeavor.

[mdsalemi]

My dear Michael, what utter nonsense.

Remember, the question YOU posed was why "Americans" call them "emergency brakes". You said, never understood why Americans call it the 'emergency brake I told you why this came about, and I gave you a real world, first person story of the use of hand brakes in an emergency. That answered your question, completely and accurately I'm afraid. Now, you don't like how the term originated? Utter nonsense? I didn't invent the term. Just reporting the facts.

[BTW, "my friend" was my uncle, and this was in Europe with a European car...perhaps you didn't read what I wrote. And indeed, it was used exactly as intended: the single hydraulic system failed, and this mechanically actuated hand-brake (yes, typically used for parking) was used to safely stop the car; this control operated the same rear drum brakes that the failed hydraulics lost control over.  And to this day, whether you call them parking brakes, hand brakes, or emergency brakes, they all are operated by systems separate from the hydraulics. And, forget cost: the same pressure exerted and maintained on a cable system could easily maintain pressure in a hydraulic system, (provided there are no leaks) but remember, that would not provide the emergency redundancy that the mechanical systems provide.]

https://en.wikipedia.org/wiki/Emergency_brake
http://www.merriam-webster.com/dictionary/emergency%20brake
http://dictionary.cambridge.org/dictionary/english/emergency-brake
http://www.audioenglish.org/dictionary/emergency_brake.htm
http://www.wisegeek.org/is-a-parking-brake-the-same-as-an-emergency-brake.htm

[Paul & Dolly]

My 1936 Alvis Firebird had 14" drum bakes, rod operated on all four wheels, The hand brake operated the same cross rod linkage, thus it also operated on all four wheels.

The elderley retired Army Officer I bought it from had very poor knees, and he told me to use foot and hand brake together - and "brace yourself" if you want to stop in time for the traffic lights ! (the brake peddle was also to the right of the accelerator) so a very entertaining first drive........

Paul

[jameshoward]

Don't blame me! Blame the Hendricks!!
I can't possibly be held responsible for what I say between posts as I'm a learning organisation on a constant quest to educate myself, etc. Probably like Donald. He has a lot to learn.

[Benz Dr.]

I can understand someone using the transmission selection P if they have an auto and never really using the hand brake. In the case of a standard trans car, I warn owners not to leave their cars in gear. Any sharp movement can break things inside the trans as they're not designed for sudden impact. Both types should be parked using only the handbrake. The P selection was intended to be used so that mechanics could safely work around the car while it was running, or so I read in MB literature somewhere.   

 On a slightly different note: never leave your ( auto or standard ) car in gear while on a trailer and only use the hand brake. Aside from the fact it should be properly strapped down, if it does start to move you won't have any P selection after that. Most tow truck drivers know this but then most owners don't and there are such things as trailers that can be rented by the uninformed.

[GGR]

I can understand someone using the transmission selection P if they have an auto and never really using the hand brake. In the case of a standard trans car, I warn owners not to leave their cars in gear. Any sharp movement can break things inside the trans as they're not designed for sudden impact. Both types should be parked using only the handbrake.

That is good advice. However, I would recommend the contrary while in storage in a safe place, as the hand brake system may end up stuck if applied over a prolonged period of time. 

[Paul & Dolly]

I agree with Dr Benz, and I am always concerned when using driveon / drive off ferries for a sea crossing.

The ferry companies here advise putting the car in gear or "P" and applying the handbrake firmly, they only tie the vehicles down if they expect bad weather.
If you do not follow their procedure you can be held responsible for any physical damage if your car moves, but you can bet they would not accept responsibility for any transmission damage.
The same may be true for "car trains" but I have never used one.

Paul

[jameshoward]

I agree with Dr Benz, and I am always concerned when using driveon / drive off ferries for a sea crossing.

The ferry companies here advise putting the car in gear or "P" and applying the handbrake firmly, they only tie the vehicles down if they expect bad weather.
If you do not follow their procedure you can be held responsible for any physical damage if your car moves, but you can bet they would not accept responsibility for any transmission damage.
The same may be true for "car trains" but I have never used one.

Paul

This is excellent advice. Ask me how I know. (Actually, I'll summarise: we moved a great many vehicles east on rail transport (something to do with our reliable and trustworthy Russian friends) and the Land Rovers were parked and left in reverse (such was the advice) with handbrakes left on. Strangely, at off loading plus a day or so, many developed significant transmission problems despite being tied down with strops. Interestingly, the vehicles that were chained down (we had some spare chains left over from tieing down the armoured vehicles) had no problems whatsoever. Needless to say we learnt an expensive lesson. On the way back, the Defenders were left in neutral. No problems thereafter).

[GGR]

I can see transmission gears flying all over the exercise field with everybody ducking for cover. Russian officers may have been quite amused behind their binoculars. Hopefully the situation is not much better on the other side. This reminds me of a story dating back to the cold war. Two guys belonging to a non-aligned country are wondering: which is worse? Capitalist hell or Communist hell? After some thought one tells the other:
- I think Capitalist hell is worse.
- Why that?
- Communist hell is safer: When fuel is available there are no matches. By the time the matches arrive fuel has been sold on the black market anyway.