master brake cylinder

[Karl kostman]

Hello Folks before I need to rebuild/recondition the master brake cylinder on my 68 404.1, I have read the maint. manual on how this is done and it looks fairly straight forward, do any of you folks have any suggestions etc. that the MB Manual might not have mentioned? Any suggestions are appreciated and I just like to have my ducks in a row prior to tearing into this.
Thanks Much
KK

 

[doghead]

Do you have a link to the TM, so we can figure out what it does say?

Otherwise, we're probably going to post a bunch of good advise that is not needed?


Maybe it would be easier for us if you just tell us what you do know, and we can go from there?

 

[Karl kostman]

Hello Doghead I do not have a TM# for you but I do have the MB workshop manual for the 404. The problem right now is that when ever you step on the brake pedal fluid comes out around the rubber dust colar on the end of the Cylinder, according to the manual if the dust collars are seated correctly and THIS happens you need to recondition the master Cylinder. I have the dissassembly procedure in the book and the measurements of gap between the piston rod and piston, their procedures are fairly complete it looks like, I love the reassembly description the best, "proceed vice versa"! They also say to use a product called ATE brake cylinder paste, What the heck is THAT?KK

 

[doghead]

http://www.ate-info.de/en/products/datasheet/ate-bremszylinder-paste-180-ml/

 

[Karl kostman]

Thanks doghead looks like I need to get a tube of this stuff prior to reassembly! Thanks again for your assistance!
KK

 

[goat whisperer]

The minimum you need to rebuild your master brake cylinder will be the "Unimog Brake Cylinder Rubber Parts Kit", I saw them at ebay USA.
Normally the metal parts can be polished and will work fine after that.
If not you have to renew the whole inner parts, in germany we can buy them for € 100,-
We also can buy a rebuilded master cylinder for € 200,-. These parts are still new old stock of the German Army...
If you can´t find the parts you need in the USA feel free to contact me, I´ll do my very best to help you...
The ATE Brake Cylinder Paste is a MUST! It seals and protects the brake cylinder from drawing water.

 

[Karl kostman]

Goat thanks for the info and to be honest I was going to rebuild the master Cyl. without the ATE, sounds like I need it? I looked around here at all the import shops and nobody has even heard of it, do you by any chance suggest an alternate product I could use in place of ATE that would work?
KK

 

[doghead]

http://www.mail-archive.com/mercedes@okiebenz.com/msg04680.html

 

[Karl kostman]

Hey guys I got the master Cyl. off yesterday and cleaned up, today my parts will be here and I will start the rebuild process, I have not taken anything apart on it yet so its all going down this afternoon. I got hold of Scott at Expedition Imports and he had some brake paste he is including in my rebuild kit so I should be set there. I will report back when completed. Thanks again for all you input on this subject, it was much appreciated!
KK

 

[goat whisperer]

View attachment Werkstatthandbuch HBZ.pdf
A drawing of the master brake cylinder... and good luck!

 

[Karl kostman]

Good evening folks, just wanted to let you know the master Cylinder rebuild went off without a hitch today. I was kind of surprised when I opened up the rebuild kit I got from Expedition Imports the piston, valves and springs are complete and come fully assembled, I have never seen that before, it was a rather pleasant surprise! After the rebuild was completed bled the master Cylinder and then bled each wheel cylinder and after filling the brake fluid container a few times all is done and the truck once again brakes just like it should! Thanks to all who offered suggestions in this process it was very much appreciated!
KK