In the process of overhauling the hydraulic system of the brakes of my 1980 TR7, I learned a lot that isn't in the Repair Operations Manual, and is thus worth sharing.

My overhaul included changing to braided steel flexible hoses, due to the recommendations made by Tim Buja, and changing to DOT5 (silicone) fluid, due to my perception of its suitability in older, low-usage cars. But most of what I will relate below is general information.

Materials Required

Obviously, you need the overhaul kits for the master cylinder, both calipers and both rear wheel cylinders. These are quite inexpensive. You will also need brake fluid, such as Castrol LMA. I bought DOT5 (silicone) fluid because it does not absorb moisture, and thus should not need to be bled as often (the maintenance recommendations for fuel-injected TR7s calls for replacing the fluid every 18 months, regardless of mileage).  DOT5 is hard to find locally; one person I talked to said it had been removed from the market because it is not allowed in anti-lock brakes. I found some for $11.88 per 12 oz. bottle, and used about 30 ounces. VB and Rimmers both carry DOT5 fluid. Dan Jones and others suggest that the moisture still gets into a system with DOT5, but it just pools up in the lowest place.

Other materials required are:

• wheel cylinder gaskets. These look to only be available from Rimmer Bros., although Dan Jones made his own easily.
• wheel cylinder circlips. New is much preferred to reusing the ones that fatigue when removed.
• replacement flexible pipes. I got mine from Ted Schumaker, but he was unable to buy fittings like the OEM hoses, so the stainless steel braided hoses have to be held on with clamps. I would recommend Rimmer Brothers instead; a set of three hoses is about 35 pounds plus shipping.
• alcohol. It is recommended when changing to DOT5 to bleed alcohol through the system first. I used less than a quart (32 ounces).
• grommets for caliper splitting. The ROM recommends not splitting (disassembling) the calipers, but neither Dan Jones nor I could figure out how to get the pistons both out without splitting the calipers. When you do, it is wise to replace the grommets (one per side). These replacements are not part of the rebuild kit. As Mark Elbers told us, you can get replacements from Apple Hydraulics at (800) 882-7753 (NY). Ask for Bob, or you may have problems. Bob says some TR7s require deep grommets, and some shallow. They will send you grommets for $2.50 each, plus $3 S&H. The deep ones are .496" OD, .323" ID, and .110" thick. The thinner ones are the same except they are .067" thick. I measured my originals at .490 OD, .290 ID, .110 thick.  You can save $5 by splitting your calipers first, and only ordering the thickness you need.

Tools required

In addition to the normal tools, you will need some unusual tools:

• 3/8" and 1/4" dowels for "butterflies." As Dan describes it, a butterfly is a dowel with a 1" slot cut all the way through along the centerline. In this slot you place a piece of sandpaper, 1" wide. You put the butterfly into a drill and use it to sand the inside of wheel cylinders and master cylinders.
• Sandpaper. I used 280, 400 and 600 grit emery cloth in my butterfly. One sheet of each is plenty.
• Air. Compressed air would be nice. I used a bicycle floor pump and an assistant.
• Circle clip remover (also known as snap ring pliers). I bought a set of four very cheap ones for $5 total at a local tool store. I have seen this set in J. C. Whitney's catalog. You may be able to get by without these.
• #3 size philips head screwdriver, or better yet, a #3 bit that you can put in a torque wrench. A normal Philips head (#1 or #2) just won't work. You will need to tighten the screws that attach the reservoir to the master cylinder to 5 ft-lbs. I expect that it is easy to overdo it.

Processes Required

The ROM should, of course, be your first reference for the operations required, but I found the need for more information.  Here is what else you might need to know.

• Circlip installation (for reattaching the wheel cylinders).  Push the circlip parallel to the centerline of the stud on which it is mounted. That is, push it perpendicular to the plane in which it will lie when assembled. I have always pushed circlips in the plane of their final position, but that sure didn't work here. Push on two of the three fingers by hand, and push on the third with a tool like an awl or a screwdriver or the nose of some needlenose pliers.
• Use the butterfly on the M/C and wheel cylinders, using the coarsest paper through the finest paper in order, if you see any signs of corrosion. I saw mild corrosion on both ends of both wheel cylinders, and the heavier corrosion on smallest bore (the inner bore for the pressure differential sensing piston) of the M/C.
• Master Cylinder pressure-differential-sensing piston removal.  I couldn't get mine out with bicycle-pump air, even though I could seal up the outlets with hose clamps and inner tubes and fingers (you'll need to leave the secondary piston in to try this operation). I took it to a shop that tried to remove it with 150 psi air, but it didn't come out, but it did blow out my hose-clamped inner tube seal. I found a shop (they specialize in Italian cars) that could remove it with hydraulic pressure; they charged me $25 for labor. Philip Johnstone reports that he makes a hook out of 1/16" welding rods for problems like this; he bends it and files it down to a 1/16" hook. Dan Jones reported trying and failing to remove this part with a hook. I tried grabbing mine with some moderate-sized electronics needlenose pliers, filed down so they would fit in the bore, but wasn't successful.
• Drum removal. I could not get the drum off with the ROM instructions, partly because mine are from a 5-speed TR7, thus using the 9" drums. Here is what you are supposed to do: Look for a hole in the silver-colored metal that you can see when you look into the big holes in the face of the drum, if that big hole is positioned 30 degrees forward of straight down. You'll need a flashlight. Push that piece of metal towards the center of the car and towards the middle of the drum with a large philips-head screwdriver. This should release the autoadjusters so that the drum comes off easily. Mine didn't, even though it had been off three weeks earlier. It seems to corrode onto the hub flange.  So stick a flat-blade screwdriver into the hole in the drum such that its wedge can separate the hub flange from the drum surface, and pound on it with a hammer. I have been successful taking the drums off this way without releasing the autoadjusters first; Mike Jeffreys has been successful by only releasing the autoadjusters; but I would recommend doing both.
• Pushing the pistons out of the calipers. As mentioned above, split the calipers in order to push out the pistons. Then apply high pressure air to the hydraulic port until the piston pushes out. With a bicycle pump, I applied the pump through a rubber washer (from an Eezibleed) which I pushed on hard enough to make a seal. My pump has a large, flat surface on its "presta" (a road-bicycle-popular valve) head. You can hold the extra hydraulic ports closed with your fingers with an assistant. Put a rag on the piston to keep it from shooting out across the room when it finally releases.
• Don't forget that you are supposed to keep the piston with the cylinder from which it was removed.
• The M/C kit comes with lots of pieces. Mine seemed to have a spare o-ring, about 1" in diameter and very thin. It also comes with a metal cap that goes on the end of the M/C that plugs into the servo. My old one stayed stuck in the servo, so I didn't replace it. There is also a white shoulder washer that goes into this cap; mine fell out when I removed the M/C from the servo and I almost didn't know it. Luckily, I dropped a wrench when reinstalling the M/C, and found the washer on a chassis piece when I went looking for the wrench.
• You should lubricate the joint between the two pieces of the levers that actuate the brake shoes from the handbrake. They sometimes corrode together and get sticky.

Summary

The task was not as big as I expected. I hope that, by telling what I learned, it can be even easier for others. I think I spent about 8 hours on it over an 8-day period, and I'm a very slow mechanic. Neither my pads nor shoes needed replacing, nor did I need to have the rotors or the drums turned. All these operations would be completed in a complete brake rebuild.

Joe Gorin, Santa Rosa, Calif. '80 TR7, 5-sp, FI, conv.