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On 21 Sep 2006 at 4:53, Arkady Mirvis wrote: > I do not have the lift and therefore need to get safely under my 72' > Squareback with auto transmission lifted to a comfortable height. > The use of the factory provided lifting point lifts both wheels on one > side. In my opinion the adjustment will be done easier and sooner if > only rear wheels will be in the air. Under what element of the car > underside will it be safe to install the jack and the stand? > Obviously one will be using one jack and 2 stands. What type/model of > jack will it be best? I promise not to forget installing chocks at > front wheels. You can use the jack and stands anywhere on the rear subframe. That consists of the heavy steel tube that runs transversely just in front of the rear wheels plus a short triangle pointing forward from the center of that tube. I use a piece of wood under part of that central triangle and lift both sides together, then put the jack stands under the outer ends of the steel tube. (That's not actually part of the steel tube, but it's plenty strong.) That gives a nice wide stance for working on the car. I see that Steve has advised you to jack up under the transmission. I see that advise occasionally, but I strongly advise against that practice. It will work, until it breaks something. When it breaks something it will often be expensive. Perhaps on Steve's Ghia there's less weight there, but the worst outcome I ever saw from this came from someone doing this on a 914, which I'm pretty sure is lighter than any of our cars. You can also lift one side at a time, but when I did that I usually went up in steps so that the stands weren't under something that was tilted so much that it might tend to slide off. > After the rear of the car is lifted, I assume that the shifter must be > in NEUTRAL position. With your AT, anything other than P will be fine. > Looking at the manual brake rubber boot, one can see that the periphery > of it is covered by the carpet. I did abandon the effort of pulling the > boot periphery from under the carpet fearing that the boot will be > damaged. Do I really need to remove both front seats and the carpet in > order to expose the adjustment nuts? The adjustment nuts for the parking brake cables can be accessed thru slits in the side of the boot. There's no need to remove the boot. Be careful not to tear the boot while you do this. > How one shall proceed with adjustment of brake shoes position inside > the drum, in what order? Brake adjustment is a critical job and I would > like to do it as close to perfection as possible. The parking brake cables seldom need adjustment. In general, never adjust the parking brake cables until after you are satisfied with all the other brake adjustments. If you suspect that someone might have adjusted the cables improperly, loosen them before you start your other adjustments. First, if your car has been out of service for long, you will probably want to remove the brake drum and shoes, free up the adjusters, and check everything else inside. Remove one wheel and the 2 small bolts that secure the drum to the hub. Don't touch the center axle nut unless it's been tampered with. I find that the best way to remove the little bolts is to use a cold chisel and cut a notch in the periphery of the head, then use the same chisel held tangentially to drive the bolt loose. The little 6 mm Allen sockets in those heads are seldom enough to get those bolts loose. Once the 2 small bolts are out, you'll probably find that the drum and hub are still rusted together. Start with one wheel still tight on one side, and the other wheel and 2 small bolts removed. Get in the car, start the engine, put it in gear and speed up the axles. Get them going medium speed, and with your right foot still on the gas, stomp on the brake with your left foot. If all goes well, the engine won't die and the drum on that side will now be spinning on the hub. If not, repeat until that one side is loose on the hub. Don't worry about the car leaping forward when you do this. Remember, both rear wheels are off the ground, so there is no way for this to push the car forward. Kill the engine, get out, and put that wheel and tire back on the car. You can leave the 2 small bolts off. Remove the other wheel, tire, and the 2 small bolts from that side. Get back in the car, start the engine, and free up the second drum the same way. Don't be tempted to just remove both wheels and tires. I've tried this and it just doesn't seem to work. Apparently, you need the momentum of the moving wheel and tire on the opposite side to produce enough force to break the drum free. Once you've got both sides free you can remove both wheels and drums. Remove the shoes and springs. Remove the adjusters; note that there is a detent spring hidden under the adjuster which you don't want to break in the process of getting the adjuster out. Once the adjusters are out, you'll need to free the star wheels from the adjusting screw. Sometimes I can do this with hand tools, but sometimes it takes a torch to warm them enough to move. Once they are free, clean out the threads until they will run fully in and out and then coat the threads with anti-seize. Put anti-seize on the outside of the cylindrical part of the star wheel body and inside the hole where it mounts. Put them back together and wipe off any excess anti-seize so that it won't fall on the braking surfaces. The adjusting screws have slots that are cut at an angle. Align them so that the deep part of the slot is facing upwards. Check the brake cylinders. The pistons should turn freely and there should be no sign of wetness around them. Put a 7mm wrench on the bleeder and see if you can get it to release. If the bleeder comes loose, check to see if brake fluid runs out readily. If it does, this is a good sign that the hydraulics on that side are good. If it does not, remove the bleed valve completely and make sure the passages in it are clear. You may have to dig mud out of it with a small drill bit. If brake fluid still doesn't run freely out of the cylinder, then you have a bad rubber hose on that side. You'll have to replace it. This is the time to do that. If you can, I would take everything out of each cylinder at this point, hone the cylinder, apply a bit of silicone grease, clean and inspect the inner part, and put them back together. NEVER use any kind of petroleum product in contact with any brake rubber part. Inspect the shoes. The friction material was about 1/8" thick when new. They wear extremely slowly on our cars, so I leave them unless they have worn to well under 1mm somewhere. Shoes for our cars are getting hard to find, so sometimes I will swap leading and trailing shoes, just because the leading shoes wear a bit faster, so this gives more lifetime out of a pair. Sometimes I even replace just one shoe on each side of the car. If you do this symmetrically, there's no problem. I advise against getting your drums turned. Note also that OG drums are made in 2 pieces: The outer rim is cast over a pressed steel face. The pressed steel face is about 1/8" thick. If you have an aftermarket drum it may be a one piece casting; these have a face which is about 1/4" thick. If you have one of these, throw it away and find a good used OE drum. The extra thickness in the face translates into less thread engagement for the lug bolts and almost certainty of stripped threads. You don't ever want to go this route. Put the shoes back on. Note that the lower springs have 2 different styles of ends. The ends with the funny recurve face away from center. Put the drum back on and tighten the 2 little bolts. I usually add a thin smear of grease on the hub to drum mating surface and some anti-seize to the little bolt threads to make removal easier next time. If you took the wheel cylinders apart, bleed them now. Reinstall the wheels, use a bit of anti-seize on the lug bolts and torque to 92 lb-ft. (You may have to just hand tighten at this point, and remember to do the final torque once the tire is back on the ground.) Now you're ready to adjust. Check the parking brake cable ends at the hand brake lever. I find that they are correct if there is about 1 cm of free thread sticking out past the locknut. If there is much more than that, loosen them, because it may mean that someone adjusted them in the wrong sequence in the past. When adjusting the cable, turn the nuts, not the cable. Now adjust the rears. I assume you can figure out how to do this. I adjust as best I can, then get in the car, start the engine and take turns applying the brakes with the wheels turning forward and backward a few times. This will center the shoes a bit and let you do more adjusting. Go back and see if you can adjust a bit more. Repeat until no further improvement is possible. You have proper adjustment when any tightening makes that shoe drag somewhere in the rotation. Note that the edges of the shoes can catch on the sides of the drum surface, but this is not the same. Go to the hand brake and adjust the cables. You should be able to pull the lever up about 20 deg. Note that there is a plate that the adjusting nut bears against. That plate crosses the lever to the other side and pivots in the middle so that it compensates for some amount of side to side difference. With the lever pulled up hard you can feel that plate thru the boot and verify that it is horizontal. If it is not, you may have to loosen one side and tighten the other to center the plate. If this leaves one threaded adjuster quite a bit different from the other side then you may need to start looking for a replacement cable. The housing sleeves on these eventually rust and collapse. I have any parts that you might need. Whew! This got to be so long and detailed that I'll keep it as a rear brake FAQ for the future. -- Jim Adney jadney@vwtype3.org Madison, WI 53711-3054 USA ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~