1. Buckeye601

    Buckeye601 Puttering Along

    FYI: On Trabantwelt.de there are two cylinder heads listed - one apparently has the typical M14 size plug hole (https://bit.ly/30jDbLe), and the other has the M18 size (https://bit.ly/2JnAcMk), which I believe is the size that is in my car. I am not sure exactly why there are two different sizes for spark plugs, but it seems like maybe mine were replaced at some point, or was perhaps built that way? Anyway, those heads may be OK, if a bit confusing.
    Last edited: Jul 9, 2019
  2. Buckeye601

    Buckeye601 Puttering Along

    Thanks for the info!
  3. A Spooky Ghost

    A Spooky Ghost Loyal Comrade

    Looks like the very early cars used this thread size. Glad to hear it's supposed to be like this!:D

    When you get around to the wheel cylinders, they only fit a certain side, there is a top, and bottom. These cannot be swapped. See a little bit down this page https://www.trabantforums.com/threads/ho-hum-brakes.2508/
  4. Buckeye601

    Buckeye601 Puttering Along

    I did read that things are very side-specific, and the kit from Trabantwelt contains the parts but they are not labeled as to where they fit. I have not received my parts yet, but I assume that will be the case. Is so, hopefully by doing one wheel at a time I can match the parts correctly and get them installed where they are supposed to go. I have a feeling I will think I got things right but when I get to the last wheel the parts I am left with will be obviously the wrong part, which will then require disassembling others and trying to get it right ;-)
  5. turbofiat124

    turbofiat124 Premium Member Forum Donor

    Yes! Don't do like I did and start opening unlabeled packages to inspect everything. Most of the brake parts on a Trabant are not symmetrical. Seems like the rear brakes are pretty straight forward since there is just one wheel cylinder but it's easy to get the front parts mixed up.

    Some of what I remember:

    1) All four drums should be the same
    2) The self adjusters between the front and rears and different lengths
    3) Wheel cylinders have angled slots in them. So one that goes on the bottom on the passenger side goes on top on the driver's side and vice versa
    4) The ends of the shoes have to be angled the same as the wheel cylinders
    5) On the rear, one of the brake shoes has a section of friction material less than the other. Make sure it's facing the correct way. Before you press the rivet in that holds the hand brake piece, make sure it's attached to the correct shoe.

    Just some of the mistakes I made. One more piece of advice. When it comes to drum brakes, I try not to use what's on the car as a guide because you never know. Whoever did the brakes last time may have screwed them up! I did a brake overhaul on my MGB and someone had put the passenger shoes on correct but the put the driver's side shoes on backwards!

    Another tip. Whenever I do drum brakes (on anything), I attach both springs to the shoes and position two ends onto the wheel cylinder then use a screwdriver or crowbar to position the bottom in place. It's a whole lot easier doing that than trying to pull on and attach a spring.

    Here is a thread I started when I did my brakes. Phil posted some good photos of the differences in parts and some diagrams how the front shoes go on.

    https://www.trabantforums.com/threads/brake-change-help.1252/page-2
  6. Buckeye601

    Buckeye601 Puttering Along

    Thanks so much for the advice. I am so glad I found this site which has so many people to share their experiences, mistakes and successes both. Being completely on my own with this car would truly be a recipe for disaster I am afraid.

    I generally detest drum brakes because I find it so easy to get confused and do things wrong. By contrast, you can hardly make a serious mistake with disc brakes unless you are really not paying any attention. Your advice not to trust that the last person did things correctly is very good advice. I will definitely check out that thread before diving into the brake replacements. I opened the master cylinder just to peek in there and there was a fair amount of gunk floating on the surface of the brake fluid (no idea what it is) but that is not a good sign for the old brakes. I think it is a good thing I just went ahead and ordered just about every part for the brake system.

    I'm not sure if this is in your thread or not, but since I am replacing all the pieces that are involved in the hydraulic brake system, does it matter then what type of brake fluid I use once everything is back together? Is there anything I definitely should not consider with respect to the fluid?
  7. A Spooky Ghost

    A Spooky Ghost Loyal Comrade

    To keep it simple dot 3-4 is fine. There is Dot 5 - but this is silicone, and not compatible with and old brake fluid in the lines. Tuns to Mayonnaise!

    Also, there is dot 5.1- which is not silicone-and is compatible with Dot 3 &4. Just has a higher boiling point. Doubt you need it...

    As with everything, please use a good brand. I go with Dot 4 synthetic on all of our stuff. On my Trabi, I made new metal lines from Ni-Cop tube. It will never rot, and should out live the car. Plus it is really easy to work with, and looks good too.

    My master cylinder had in it, what can only be described as chunky mud! :eek:

    If you are using the old metal lines, flush / blow them out with some acetone & air. Be sure and wiggle the metal pipes gently, check for rust, kinks, or being crunched by a jack.

    My brake system was redone 2-3 years before I got it... To be fair, somebody didn't realize there are different types of line fittings, and they just screwed them all together. So plenty of air got in it.
    Last edited: Jul 12, 2019
  8. Buckeye601

    Buckeye601 Puttering Along

    I ordered all new lines and hoses - the old ones do not look all that bad overall to be honest, but in my experience (or my luck), things like fittings tend to break when they are taken apart after so many years. If any of the lines are still good, I will just keep them as spares.

    So, since I am replacing the master cylinder and brake cylinders too I could in theory use whatever I want for fluid. I guess the one advantage to DOT 5 is it won't absorb water and cause issues like the DOT 3/4 ones do, so if I do not drive it much in the winter maybe that would be beneficial, but also maybe not necessary either. Whatever I use, I probably should make sure to label things so that in the future it is clear what to use in the car so nobody needs to guess.
  9. trondd

    trondd Loyal Comrade

    I wouldn't bother with DOT 5. It has no benefit you would actually see, costs a lot more, and runs the risk of a big mess if someone adds the wrong type later.

    I put DOT 5 in my Chevelle when I replaced the entire brake system (including all the hard lines) and now, in hindsight, I have no idea why. I've had no issues with DOT 3 or 4 in several classics, daily drivers, and even a race car.
  10. Buckeye601

    Buckeye601 Puttering Along

    I think I will stay away from the DOT 5 then. I just need to get the parts in from the Fatherland before I can move forward. :)
  11. trondd

    trondd Loyal Comrade

  12. A Spooky Ghost

    A Spooky Ghost Loyal Comrade

    Silicone fluid has some benefits. Though a big issue is it can feel kinda squishy when a quick stop is needed. In theory you are supposed to flush your brake fluid every 2 years. I say theory because almost no one does this. Right up there with flushing antifreeze, and changing " lifetime fluid"..

    When fitting the new master cylinder. Be certain to have some pedal free play in it. For what ever reason, my car was adjusted with no play, and I never checked it. On a 100' F day last year, the rear brakes locked solid on the interstate at 70mph.. Had to open a rear line, to let some pressure off.
  13. Buckeye601

    Buckeye601 Puttering Along

    Yikes! That had to be an adventure at that speed. I will definitely keep that in mind. Right now my car has the maximum amount of free play since it does not offer any resistance all the way to the floor :).

    I have yet to meet anyone meticulous enough to change the brake fluid outside of when there was work being done, and even then, most people just add whatever fluid is necessary when bleeding the brakes and don't do a flush even then. I'm sure there are people who do so, but none in my circle of acquaintances anyway.
  14. Buckeye601

    Buckeye601 Puttering Along

    OK. In reviewing my order from Trabantwelt, it looks like I may have ordered the wrong master cylinder. Oops.

    It appears there is a two-circuit and a single circuit one, with the single circuit one listed in the brakes section for the Trabant 500/600 (which I was not looking at while ordering since I have a 601), and the dual circuit one listed on the brakes page for the Trabant 601. I was ordering parts from the 601 page and did not pay close enough attention - I guess I just assumed my car had a dual system.

    The one on my car has the reservoir for the fluid apparently threaded directly into the single hole on the top of the master cylinder. The one I ordered has three connections on the top of it. I assume the two outermost ones are for the rubber hose connections to the fluid reservoir (which has two "halves" internally like most modern brake systems), and the center connection is likely for one half of the brake system, with a connection near the front for the other half, though the pictures only show a single side view so you can't get a good idea what is going on.

    I assume I will need to place another order now to get the correct master cylinder and have a cylinder I can't use. What I am wondering is if there is any practical way to "convert" from the single to the dual system? To be honest, it makes me a bit nervous that the system in the car is apparently designed such that a leak in the system could take out the entire braking system rather than "just" the front or rear brakes. I know the rear brakes on pretty much any car are not really designed to stop the vehicle on their own, but having at least some brakes in the rear would be preferable to none at all. Relying on the driver to be aware enough to immediately grab for the "emergency brake" handle after pressing down the pedal down and find no brakes seems like a perfect recipe for a crash, but perhaps that is what the engineers expected owners to do if the single system failed?

    Does anyone know if it is possible/feasible/a good idea to switch over to the dual circuit setup, and if so, what might be involved in doing so?

    I uploaded pics from Trabantwelt and also (a not so great) one of my car to show what the master cylinder in the car currently looks like - located directly beneath the battery in case it is not obvious given the poor picture quality.

    Attached Files:

    Last edited: Jul 13, 2019
  15. Buckeye601

    Buckeye601 Puttering Along

    Does anyone know what is in the pictures I uploaded? This is mounted near the driver's door under the dash. It appears to have a single red wire running to it, and inside of the hole in the front there is what looks to be a copper contact, as if something should be plugged into it, but there is obviously nothing inserted into it. I'm just curious if anyone knows what it is for?

    Also, is there any documentation available to tell me what the correct fuse sizes are for the ones in the fuse block? I had a Mercedes with this type of fuse, and they were color-coded as to size. Are these all the same capacity? The reason I am asking is that my wipers do not work, so checking fuses is always a good first step. I have no idea which fuse is protecting the circuit for the wiper motor, and I am not sure what the size(s) of fuses are in the car.

    Attached Files:

  16. Berlin89

    Berlin89 Puttering Along

    That's funny, I never noticed that mystery part. :eek: I went out and looked at mine and there's two wires coming from it.
  17. trondd

    trondd Loyal Comrade

    You could convert to dual, I would think. Devil is in the details. Sometimes the fittings in the brake lines are different sizes so might have to change them or adapt them.

    The jack under the dash on the driver's side is your power plug for anything 12V. For a work light or, in these days, your mobile phone charger. Trabantwelt sells an adapter to a modern 12V car socket but I can't find it now and have no idea what it's called in German. :D
  18. trondd

    trondd Loyal Comrade

  19. A Spooky Ghost

    A Spooky Ghost Loyal Comrade

    It wouldn't be too hard to convert to a dual system. You would need a separate/ dedicated line from the rear, to the master cylinder. Really it is that simple... A dual master is much safer.

    When one of the systems fail, you still have the other. Where as on the old system, you loose it all. If you already didn't, you'll need a dual circuit reservoir, and the hoses to it. Don't use fuel hose! Needs to be from trabi welt. Or go to a tractor supply, and get chemical resistant pressure sprayer hose.

    It must say EPDM. This is the rubber type..
    Last edited: Jul 19, 2019
  20. Buckeye601

    Buckeye601 Puttering Along

    I definitely like the idea of a dual system for safety's sake. I did order the "kit" for the dual master cylinder which includes hoses, clamps, reservoir, and a seal. I probably need to take the current one off and see if the mounting bolts line up, how much difference there might be between the two where it meets the firewall, and determine what would need to be hooked up to what on the new one (once it gets here so I can see what connections are there etc.). I am not sure what the routing is currently of all the brake lines, so I would need to see in particular what heads to the back brakes and figure out what I need to add. I assume there is some sort of bracket that holds the reservoir in place, so I would need to rig something up for that too but I imagine that will be simple enough.

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