Parts:
- A long piece of 3/8" hose. It needs to be strong enough not to collapse under about 10 psi of vacuum. I cut a 20' piece from a 50' pneumatic tool hose I bought for something like 8 dollars at Big Lots.
- A big jar with a metal lid. I used a 2-quart jar that I bought (filled with ridiculously bad dill pickles) for 99 cents from Big Lots.
- A shower flow diverter. I got lucky and found a cheap plastic one for 3 dollars at Big Lots. (Notice a pattern?
)- A short (1 or 2 inches) 1/2" galvanized steel pipe nipple. Several dozen cents at the hardware store.
- A 3/16" brass hose splicer. 1/4" would probably do too. Another several dozen cents at the hardware store.
- A brass 1/2" FIP to 3/8" male hose barb fitting. About a dollar from the same hardware store.
- Optional: a 3/8" hose splicer. I didn't use one but it could make it easier to use.
- A few feet of clear 3/16" vinyl tubing. Another buck or two from the hardware store.
- Miscellaneous stuff: solder, flux, a torch, zipties, hose clamps, Teflon tape.
Assembly:
- Empty the jar of any contents. Wash it out and dry it out.
- Cut two holes in the lid of the jar, not too close to the edges. One hole should be just big enough to fit the 1/2" nipple through (ideally you'd have to thread the nipple in) and the other should be just big enough to fit the hose splicer in.
- Put the two fittings in, and solder them into place. I used Goop at first, but the brake fluid actually ate through the Goop. Soldering seems like the sensible way to go and is easy to do. Just make sure not to burn the edges of the gasket that's built into the underside of the jar lid. The easiest way is to pour some flux around the base where the fitting attaches to the lid, then wind some wire solder around it a few times, and then apply heat with a propane torch at the top of the fitting. The heat will flow down the fitting until it activates the flux and melts the solder. If you did it right, it'll nicely tin the fitting and the lid.
- Let the lid cool before you touch it.
- Cut a length of vinyl tubing as long as the jar is tall, and attach it to the underside of the 5/16" fitting. Use a ziptie or hose clamp if necessary to hold the tubing in place.
- Put the lid on the jar.
- Thread the flow diverter onto the 1/2" pipe nipple sticking out of the top of the lid. Use Teflon tape to seal the threads.
- Thread the 1/2" FIP to 3/8" hose barb fitting onto one of the diverter valve's outlets. Again, use Teflon tape.
- Attach the remainder of the vinyl tubing to the top of the 5/16" fitting and attach the 3/8" hose to the 3/8" barb. Use zipties or hose clamps if necessary.
Usage:
- Attach the 3/8" hose to the intake manifold. I unplug my brake booster hose from the manifold and put the 3/8" hose in its place. If you use a 3/8" hose splicer you could unplug the brake booster hose from the booster instead of the manifold and attach there if you wanted.
- Turn the diverter valve's handle so that the jar is open to atmosphere (i.e. the "flow" is "directed" towards the end that has nothing attached).
- Start the engine. It may be helpful to raise idle speed by wedging the throttle open with a quarter or something.
- Seal the threads of the bleeder screw on whatever you're bleeding. If you have a speed bleeder in there it should already have sealed threads. If not, remove the bleeder screw, clean the threads off, properly apply Teflon tape to them, and reinstall the bleeder. You should only have to do this once.
- Fit a closed-end or flare nut wrench over the end of the bleeder and then attach the 5/16" hose.
- Turn the diverter valve fully in the other direction, allowing the engine to depressurize the jar. The engine may stumble for a few seconds when you do this. Wait a few seconds for the jar to depressurize.
- Remove the brake master cylinder cap. If desired, pull out as much fluid as you can with a turkey baster or syringe and replace with new fluid. In any case, fill the reservoir up to the top.
- Loosen the bleeder screw. As soon as you get it open air and fluid should start flowing out into the jar. Make sure the fluid level in the master cylinder never falls below the low mark.
- Once you're satisfied with that bleeder, tighten the bleeder screw back down, switch the diverter valve (you'll hear the vacuum release to atmosphere), and remove the vinyl hose from the bleeder.
- Repeat with any other portions of the system you may need to bleed.
You might be able to get away without the whole diverter valve setup, but it does allow you more control over the vacuum. If you have speed bleeders you can use the diverter valve to start and stop bleeding. And, you can allow the engine to depressurize the jar before opening the bleeder screw.
You might want to reset your ECU after you're done with this, since the temporary vacuum leak might adversely affect its fuel trims.
[edited to correct the vinyl tube size]
Not to mention using the brake booster for brake bleeding. GENIUS!
. The unit is actually probably right on the garage floor next to the Supra which is on jackstands with its transmission out. Feel free to borrow it if you want too.
