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Catching up with what I've done to my car:
Behind the pedal cluster before removing the old brake cylinder. The accelerator is at the top of the photo; the threaded rod goes into the back of the master cylinder.
Before I discovered the leak in the master cylinder, I thought the main front-to-back brake line was the leak, so I ended up cutting it to remove it. So now I need to manufacture a new brake line to replace it. The ends of the original line are bubbled flared, I can't buy a tool to bubble flare brake line, but I discovered that the other auto parts store in town sells brake line sections with bubble flared ends:
Here's one of the bubble flared lines that I've bent and is ready to install:
So, the current state is that the new master cylinder is in and I'm starting to put the brake system back together again. Hopefully more progress on Saturday.
I spent the afternoon and evening working on replacing the beetle's master brake cylinder and preparing a new rear brake circuit. I'm way too tired for a full entry, but here's the revelation of the day:
I found the leak in my brake system. It was leaking out the back of the master brake cylinder:
Note: both brake circuits have been drained and open to the air. The rubber boot on the back of the old master cylinder was completely full of brake fluid. It's not supposed to be; it's a dust cover.
One of the very valuable things I learning in my first skim through the Bob Hoover sermon book is what the flare on the ends of the brake lines is called. I mentioned recently that the brake lines that I bought at the parts store were double-flared, but they were different than the lines in my beetle.
Well, hoover's sermons told me what I didn't know, which is what the VW's lines are called--they're called "bubble flared" lines. After I knew the name for them, I found this great page on "Tom's VW" with photos and explanations.
So now I know what to ask for at the parts store, which should get me the rest of the way. Off to shop.
There's a gentleman by the name of Robert Hoover that has been a volkswagen mechanic for a very long time, both ground vehicles and flying ones. Back in the day, before the world wide web, he posted many of his opinions and stories and such in a series of documents that are known as the "sermons of Bob Hoover". He took them down eventually, tried selling them on CD, someone else posted them for free, so he stopped doing that.
But Robert writes in his blog, the sermons are now being sold as an 800 page pdf e-book. I've been reading through them this evening. They're excellent reading, some funny, a few I dis-agree with, many packed with realy information and insight.
One of the stories I'm reading is Robert delivering a car to Washington from south California, and having to refurbish a VW bus to get himself back home. When talking about slowly bringing the brakes up to usable, at the end of a day's entry, he makes the statement "One step at a time. Do it right and you only have to do it once." Which is a statement that applies equally well to living life, I suspect.
If you're interested in Volkswagens or mechanical stuff at all, or in interesting reading, I suggest buying a copy.
Sorry I haven't posted in a couple of days; I'm planning on diving in and getting the brake system put back together in my beetle on Saturday.
I worked on the beetle's brakes tonight. My chief concern at the moment is replacing the line that that runs from the brake master cylinder in the front of the car to the rear brakes.
Here's the master cylinder currently in the car.
The two rubber lines that come in from the top of the photo are the fill lines from the brake fluid reservoir. The metal line that goes from the cylinder to the right is the line that has the leak in it. In fact, the stains around where it goes into the body are probably a result of that. The other metal line, the one that goes to the left, actuates the front brakes.
This "T" splits to the two front brakes.
The line in the lower right comes from the master cylinder, the line coming toward the camera goes to the left front brake, and the line that goes out of the top of the T and away from the camera goes to the right front brake.
This view is from outside the left front fender.
A metal line comes from the T in the body and connects to the rubber line at upper left, which continues off the photo and descends down the right side toward the wheel.
Here, the rubber line has been replaced with new braided lines. The metal supply line has been disconnected and turned down to drain the front brake circuit. I want the brake system as dry as possible before I replace the master cylinder.
Here's the other end of the front-to-back brake line, it ends in a T as well. The line on the left of the T comes through the body, the black line goes to the left rear brake, and a metal line out of view supplies the right rear brake.
Before I thread the new brake line, I need to remove the old one from the T.
Here, I've cut the old brake line to make it easier to unthread the compression nut from the T.
Well, now I'm comitted. Most of the other changes and repairs I've done to the car were reversible. I could put back the old starter, for instance. This one is permanent. I know that the front to back brake line was leaking badly and probably causing damage to other parts of the car, but this is the first thing that I can think of that I've altered in the car that I can't put back without a tremendous amount of work. I guess I'll find out how deep the rabbit hole goes. :-)
I have a checklist for all the stuff I need to do to the beetle. One of the easy items that I wanted to do next was to replace the brake hoses in the front of the car. Easy to do, and they look nice, and it's tow things to check off the list.
I disconnected one end of the front right brake line, and the metal supply line kept producing fluid. It was obvious that it was actually coming from the brake fluid reservoir. I put the line back:
But that got me to thinking:
When I put the car up on jack stands in October or whatever, the final reason was because the rear brake circuit was losing enough fluid without driving the car, that the real reservoir was empty if I left the car overnight. I had assumed since I didn't need to be driving the car for it to lose fluid that the problem wasn't in any of the brake lines, that it was in the lines running from the brake fluid reservoir down to the brake master cylinder. The fact that one time fluid ran out of the frame drain hole seemed to confirm this.
However, I got a good look under the front of the car recently, and the fluid lines from the reservoir to the master cylinder don't run through the frame anywhere. Today I realized that if there's a leak in the brake lines, the system will drain even when not using the brakes. Those two facts together mean that the reason that the rear brake circuit was running dry was one of the master-cylinder-to-wheel lines in the rear brake circuit. Well, the most likely cantidate is the main front to rear metal brake line, and it does go through the frame in a spot just to the right of the driver's feet, and then runs through the passenger compartment to the back of the car.
So I think I'm going to have to replace the main front to rear brake line in the car to really be able to drive it safely. This is why I went seeking brake lines. I'll probably be lazy and attach the new brake line to the bottom of the car, which isn't pretty but it's much simpler to install.
It seems that I'm going to have to replace the main front-to-back brake line in my beetle. I have a bit of a problem thought that's confusing me.
In the following two photos, the left brake line on the left is stub line that connects the right rear brake hose to the slave cylinder on that wheel. The right one is the end of a piece of brake line that I bought at the parts store. The end is called a "double flare". I don't know what the left one is called.
Here's the socket in the master cylinder that the main brake line has to screw into. The bottom of the hole is bevelled down, to match the convex flare in the left brake line.
One thing I learned in graduate school is to take lots of photos of what you're working on. Even if the photo doesn't eventually turn out to shed light on what you think you were taking the picture of, sometimes something totally unrelated will be in view that's useful in some other way.
Working on my beetle yesterday, I was vexed that there are too many things in the way for me to get at the brake warning light, which is at the top center of the dash board and so is obscured from the rear by the windshield wiper motor and the radio. There's a bunch of wires that apparently go toward some of the switches on the dash, but I don't know which ones go to which, necessarily.
It occured to me this morning that I could actually count the wires that are in that bundle and deductively try to fiture out which wires are which. Here's the bundle:
Note there are two red wires, one bigger than the other, in this bundle, and a blue wire. Comparing that to this section of the wiring diagram that contains roughly the same wires (E1 is the lights switch, K7 is the brake warning night, E9 is the blower fan control switch and E3 at the bottom is the emergency flasher switch):
The only blue wire in this whole area, and one of the only two blue wires in the car, are in the group that go to the brake warning light, which is what I'm looking for. In fact, as the wires go toward the left side of the picture, there seems to be a separation between the fatter wires on the top and the skinnier wires at the bottom, and each bundle has a red wire.
Now there is one other red wire in the general area, which goes to the emergency flasher switch. As I look for the red wire that goes to the brake light warning, I need to make sure that whatever red wire I have isn't the one to the flasher switch. This shouldn't be a problem because both the red wire that goes to the lights switch and the one that goes to the emergency flasher switch connect to the fuse box, wheras the one that goes to the brake warning light ends up connecting to wires that go down to the brake master cylinder.
When you start working on something in a vintage car, you will most likely be doing something beneficial, but often now what you set out to do.
I worked on my beetle tonight, with the goal of testing the brake circuit warning light. I couldn't get to the back of the light to test it, but I did find out why the washers don't work.
Here's the back of the trunk before I started.
Now here's the same area with the ventilation box partially removed. Notice the end of the hose that I've highlighted at the left of the photo. That's part of the hose that delivers the fluid to the washer sprayer.
Now test the hose by pulling on the washer lever on the steering column, and voila! That's where the washer fluid was going:
I can't get to the back of the brake warning light just yet, but it's interesting to go through the wiring (kind of a rat's nest) and find the corresponding places in the wiring diagram. This attachment point is where a lot of the grounds connect to the body
And here's that spot in the wiring diagram
So I'm not going to be able to test the brake warning light at the moment; I'll have to find another way to get at it or at least its wiring.
I finally found a program to create electrical schematics. It's called gschem and it's packaged under Ubuntu. That package seems to be a full electronic design suite, which I don't need, but it does make nice schematics.
I'm using it here to document the change I made to my beetle's electrical system yesterday. I don't have a driver's side door switch that works, and they don't make them any more. Here's the system as it's designed:
Notice that neither part of the upper part of the left door circuit is connected to ground. Notice also that the right door switch only has one contact, and that grounds to the case (which grounds to the door frame). The door switches are shown in the "door closed" position, and the ignition key switch is shown in the "key out" position.
To duplicate the functionality of the left door switch, I installed a right door switch (single pole, case-grounding only) in the left door switch spot, and wired in a relay to duplicate the double-pole isolating structure.
The system works, although there's a loud click when the dome light turns on when you open the driver's door.
The volkswagen beetle, like any other car, has switches on the doors that turn on the interior light when the doors are opened. In the later years, the original beetle also had a buzzer that sounded when the driver's door was opened with the key still in the ignition. The wiring for this was a double switch in the door pillar that activated two different circuits, one to drive the light and the other the buzzer.
I've seen instructions how to dis-able the buzzer by pullout out the door switch, disconnecting the wires that control the buzzer, taping them up up and then pushing those wires into the door pillar. I don't remember where I read that, and I'm glad I don't. I don't know what kind of lame-brain would dis-able something in a car's wiring by disconnecting wires and then leaving them floating around inside the body, even if they're taped up. First of all, electrical tape comes off over time, and then you have a wire that randomly grounds and sets off the buzzer. Secondly, if you don't like the buzzer, why don't you, say, UNPLUG THE BUZZER itself? It's one of the three relays that are plugged into the relay rack right about the fuse box. Then you can always restore it to original operating condition by putting the relay back in. (And I'm not talking about vintage car issues; someone someday might own your car, and they might want to have it in original working condition.)
Ok, enough bitching. At some point, something must have been wrong with the double switch in my beetle (I don't remember now). I know that the buzzer wasn't working, so I think I pulled out the switch and was going to restore the wiring. Well, the switch was broken. I bought a couple of used switches at a VW show last year, and last night I went to install them. I started by fishing the relevant four wires back out of the hole in the door, which was no picnic:
I discovered that none of the switches that I had worked. I couldn't get a reading on them with the ohm-meter. You can't buy new versions of those switches as far as I can find. You can buy one switch that grounds a terminal to the car body when the door opens. But the way the buzzer is wired, that doesn't work, because the way the circuit is designed, neither side of the switch is grounded.
So I wired up a relay from a supply that I have around for just such occasions. This is a 3-pole, single throw relay, which is totally overspecced for this application but it means that I could do the job with one extra component. I soldered wires to the coil inputs of the relay, a short wire to go to the fuse box and a long one to go to the door pillar switch.
The left side of this photo shows an original switch (two pole, single throw, non-grounding) and the right side shows what I'm replacing the switch with (single pole, single throw grounding-only switch and a triple pole, single throw relay).
The setup on the right is big and cumbersome, but it works.
Here's the relay wired up and successfully tested. You can see the four wires that I pulled out of the door pillar and re-routed to plug into the relay.
The new grounding switch, wire from the relay attached, ready to install.
Door switch in and ready to go.
The final installation in the front of the car. The relay is duct-taped to the top of the gas tank, with a piece of cardboard for padding.
I wouldn't want to drive cross-country this way, but this is good enough to drive around town for testing.
Now there are definitely more efficient ways of doing this. The reason I used this monsterous relay is because I had it and it did the job all in one. However, two very small relays wired up together so that their coils were controlled by the door switch but they switched the two different output circuits would work just as well and be much smaller and easier to deal with, but I didn't have any more suitable relays in the house. The next time I get to radio shack, I'll pick some up and maybe improve this installation.
Since I'm replacing the brake drums in my beetle anyway, the outer bearing races need to be removed from the drums. I took them out tonight; they were much easier to remove than I thought.
Since the wheels are basically all taken apart on the right side of the car, it's a good time to replace the brake hoses. I'm replacing the old rubber lines with new lines reinforce with steel braided jackets:
Here's the right rear suspension arm. You can just see the brake hose at the top right of the photo.
Here's the upper end of the right rear hose; it attaches the metal line that runs the length of the body.
I have to first remove the metal line that comes from the wheel.
With the metal line removed, I just have to get this clip out of the bracket to get the hose free on the lower end.
Old and new brake hoses. The wheels move around in relation to the car body, and the brake hoses are there to be a flexible means to deliver the brake fluid to the brakes, which ride with the wheels. It's very important for them to be long enough. The metal line is just slightly longer than the stock rubber line, which is probably on purpose.
The finished product. This is the first new part that I've put actually on the car during this brake project.
Wheel bearings from the right side of the car have been soaking and they're much cleaner:
Since the wheels are all off and I need to wait for brake drums to get here, I'll be working on brake hardware next.
I'm becoming more and more interested in the wiring of my beetle as I contemplate launching into a project of adding gauges and electrical components and updating stuff. Before doing that, I need to understand the wiring as designed and implemented in the car.
As part of this process, yesterday I made a high-resolution scan of a copy of the wiring diagram for my car that I have. People have posted copies of the orginal wiring diagrams, but I wanted higher resolution versions, so that I can post modified versions.
Here's the main scan (reduced in resolution, of course):
One of the diagrams I wanted to produce was to highlight the wires in the car that are live, connected to the battery without fuses at all times.
Here's a partial diagram of the fuse box. Note the red wire that I indicated with a purple arrow. That's the main wire directly from the battery.
The other two red wires shown here are connected to the main battery wire with a metal strap, all on the unfused side of the fuse box.
Here are the actual wires in the car:
This diagram shows where those wires go in the car. From the fuse box on the left of the diagram, one red wire comes through the wiring harness from the battery that's at the right of the diagram (in the rear of the car). One red wire goes up to the light switch, the other goes down to the ignition key cylinder switch.
The rear brake drums in the beetle are even worse than the front ones, as it turns out. The rear drums are smaller and they have splines in the center that mate to the stub shafts:
It turns out that the rear drums don't have their maximum rated diameter marked on them, at least that I could read. I got the maximum diameter out of this book (which is an absolute necessity for owning a beetle):
The maximum diameter is 9.114 inches, or 9 and 3.6/32. The left rear drum is about 2 32nds over diameter (remember the other end of the ruler is set at the 1 inch mark):
The right rear, one I'd already decided to replace, was even worse; it's been machined almost an eighth of an inch past tolerance:
Just out of curiosity, I measured the new brake drum for the right rear.
The two marks I've put on the ruler are the spec diameter and the maximum diameter. The amount that the drum appears to be bigger than spec may just be my measurement technique; the point is it's consistent with the correct measurements.
So for those of you keeping score at home, the four drums have been machined past spec by 1, 2, 2, and 4 32nds of an inch respectively. Time for a new set.
A vintage car is never done. I'm doing the brake and wheel bearing on my beetle project because I want that to be a "done" item for the next 30,000 miles that I drive the car, but even doing a job like that, you find out other things that need to be worked on.
One of the things that are often done is to have the brake drums "turned", or resurfaced to provide better braking friction. The important surface of the brake drum
is the inside surface where the brake shoes rub. Because resurfacing the drum is removing material from the inside diameter, there is a maximum diameter that is allowed before the drum should be replaced:
So the interior diameter of the drum should be 9.822 inches or less.
Up until today I didn't have any measuring instrument that could measure a diameter that large accurately enough. I went to Sears and bought a combination square with a stainless steel ruler marked in 32nds of an inch, long enough to measure the brake drums.
Here's the ruler set up to measure the drums:
9.822 inches translates to (in very non-standard notation) 9 and 26.3/32 inches.
To maximize accuracy and eliminate the quality of the machine work on the end of the ruler, I placed one side of the drum exactly on the 1 inch line (which means that you have to subtract one inch from the measurement you find on the other end):
Below I've marked a red line at 10 26.3/32. This is the measurement of the right front drum. It's at least 1/32 of a inch too big already, without any resurfacing (that's 30 thousanths past tolerance for you machinists).
The left front drum is even worse:
So the front drums are both out of wear tolerances, which means I ought to get new ones. I already got one for the right rear because the inner surface of the drum was badly gouged, so I might as well get new all around.
I managed to put enough time to together today to get the last of the right side wheel bearings off my beetle today.
In addition to being busy and having difficulties, it's been fairly chilly, which makes working in the garage, particularly lying on the floor, not very fun.
I had to take the brake fluid line off of the right rear wheel cylinder to remove the brake plate. I had to use this 11mm open-end wrench this wierd angle because the brake line comes in between the bleeder bolt (nearer the camera) and the bolt that holds the cylinder on the brake plate (in the shadow of the wrench).
With the brake line off, I could remove the brake plate from the wheel housing, but not totally from the car. The parking break cable was still attached to the brake plate, so I just set it on the floor.
Here's the inside face of the suspension housing that holds the right rear stub axle. In the center, you can see the inner race of the ball bearing.
Around the outside of the hole is the grease seal. This must be removed to get the bearing out. The seals turned out to be much tougher to remove than I thought. They are rubber-colored on the outside, but there's a stiff metal pieces that makes it fit fairly tightly, which is part of its function. To remove it, you need to take a center punch and pound on it until it has deformed enough so that you can get a screwdriver in beside it:
This is the inner seal along with the center punch I used:
Here are both right rear wheel bearings. The ball bearing on the left is the inner bearing and the roller bearing on the right is the outer bearing.
Perhaps the markings on the left indicate that this bearing is original to the car?
An actual exploded diagram of all the stuff that came out of the bearing assembly in the car. To the left are things farther inside toward the transmission, and to the right is toward the outside. I placed items above one another that are inside and outside each other.
Here's the front bearing hardware that needs to be cleaned.
All the bearings and some of the hardware are soaking in mineral spirits to get the grease off of them for inspection. If I had to guess right now, I would say that most likely I can put those bearings back in, I don't need to change in any of my spares.
I attended the sheet metal Sportair Workshop last weekend in Oshkosh. I took the composite workshop a couple of years ago, so now I've spent a weekend with two different construction techniques.
The project in this workshop is to build piece that is similar to the section of a wing. It has a wide front spar, a narrow rear spar, one rib at each end, it's riveted together, and it has an inspection plate on the bottom. The top surface has flush rivets, whose heads are level with the surface:
The bottom surface has universal head rivets, which are rounded but the heads stick up above the surface:
The round plate with three screws is the inspection panel. These are put in aircraft so that internal moving parts (like control linkages and pulleys) can be inspected and lubricated during the annual inspection that all aircraft must undergo.
Here area couple of photos of the flush rivets with a quarter for scale. Flush rivets are used in aircraft that go fast to minimize drag. Flush rivets are the little round things that you see around the door of an airliner as you get on board.
I took this workshop to practice the techniques and to get a feel for whether I liked doing them for a while. The answer to the second is yes, I think I could do this sort of thing long term. Here are a couple close-up photos of universal-head rivets. This first rivet is a good one; the factory head is on the left and the formed head (formed by squishing the rivet in a squeezer) is on the right, and are directly across from each other.
Here's another rivet where they're very skewed from each other. This happened because I didn't have the rivet squeezer perpendicular to the surface of the metal. It looks like it was tilted to the left at the top from this point of view; the formed head on the right is squished down and the manufactured head is deformed up. This is a much weaker connection between the two sheets of metal than the rivet above.
Aluminum sheet metal designs have a large margin, only (for instance) 75% of the rivets in some designs need to be good for the structure to strong enough to meet its design criteria.