A small hydraulic system like that of a motorcycle front brake, having a helluva time getting air out. I may need to bleed the small master but having issues using my hand pumped which pulls it from the master down to the caliper vent. So, get a big syringe on the caliper, open the bleeder and push juice back toward the master hopefully popping the air UP.
Where to get a big syringe? Does it work?
I have one of these but can't poke a bleeder sucker in the master's cap.
I haven't done any reverse bleeding, so no experience with that.
However, I've had pretty good experience with tying the brake lever back with a piece of rubber or string and leaving it like that over night. With a lot of older bikes this opens up the system enough for the air bubble to burp into the master cylinder.
If you search for something like 150ml syringe on Amazon there's a bunch of options (things get weird over 200ml just an fyi and at 300ml they stop pretending.)
I've reverse bled both car brakes and aircraft brakes with a syringe. Works pretty well as long as you're careful. The Mityvac or Phoenix systems worked a lot better however.
I did it the hard way, remove the caliper and hold it above the master. Dirt bikes don't have much stuff to remove in order to bleed this way.
I have before, Using that exact kit.
I have to bleed the slave on my 944 turbo.
I used my DIY pressure bleeder (made from a garden sprayer for $10) and some parts from my vacuum tester kit to get a tight fit at the nipple (hehehe)
I've also done that on a 944 clutch, using an old-fashioned oil "squirt" can full of fluid, and rubber tubing connecting it to the bleeder on the slave cylinder.
I’ve used a two stroke premix syringe with a rubber tube attached. It fits the bleeder well. Couple bucks at a bi mart
In reply to Danny Shields :
The V8 944 guys figured out that they could remote mount the bleed port near the master cylinder with some AN fittings and hose.
Basically makes bleeding it pretty easy.
Stefan said:I have to bleed the slave on my 944 turbo.
I used my DIY pressure bleeder (made from a garden sprayer for $10) and some parts from my vacuum tester kit to get a tight fit at the nipple (hehehe)
I did the same thing with my Spyder. DIY pressure bleeder to bleed fitting on slave cylinder, used a spring clamp to seal the vinyl tubing to the slave cylinder bleed fitting. (OK, fine, nipple, hehehehe) Worked great. The kit shown in the first post should work great for it - put brake fluid in the mityvac reservoir and put the output tubing around the bleed fitting, clamp it with a small spring clamp for best results. Make sure to flush all air out of the lines before connecting it to your bleeder. It's possible I'm misunderstanding how the mityvac works but if it works to push fluids into that tubing then you've got what you need. The only thing you need to do on the master end of things is pull excess fluid out before it overflows.
akylekoz said:I did it the hard way, remove the caliper and hold it above the master. Dirt bikes don't have much stuff to remove in order to bleed this way.
Just did this over the weekend on a motocross bike with a new front brake line. I've bled a lot of brakes over the years but this thing tested my patience.
You can get big syringes from TSC - at least here you can
I bought one of these from Amazon
And have done a dozen cars with it. The unit itself is a cheesy POS but the technique is sound. On some cars you can listen to the brake reservoir from under the car and tell when the bubbles stop.
I have done it before and can tell you that if your hose slips off the bleader while under pressure you will be royally pissed.
Danny Shields said:I've also done that on a 944 clutch, using an old-fashioned oil "squirt" can full of fluid, and rubber tubing connecting it to the bleeder on the slave cylinder.
Did the same with my manual w123 slave cylinder.
Pull the bleed nipple 
out of the caliper and use yellow teflon tape (for gas fittings) on the threads. Refit. Go to your local aquarium supply and buy a one-way valve for fish tank air supplies. Attach to bleed nipple 
with appropriate lengths of hose on either end and place the final exit into a glass jar with enough brake fluid to cover the end of the hose. Fill the master reservoir with fluid. Crack open the bleed nipple 
around 1/8-1/4 turn. Use the brake pedal to pressurize the brake system as often as necessary until the exiting fluid 
has no bubbles.
I've done it on several mountain bikes with disc brakes. They are obviously smaller systems, but the factory bleeder kits are just big plastic syringes.
I did this once With a garden sprayer connected to the bleeder valve.
The bad thing was there must have been trash in the lines because the master cylinder wouldn't build pressure shortly after.
(Typical 100K+ Mile Toyota with brake fluid that had never been serviced since it left the factory)
So It does work but YMMV (your mileage may vary)
I have a rubber tipped blowgun set up to use with my pressure bleeder. I use it all the time for clutch hydraulics, which suffers the same difficulties as a bike brake.
Works a treat. Your king sized syringe should work properly, as long as you have it bled so you are only pushing fluid.
Thanks folks! I'll be off to TSC soon, the new shower just showed up so today I start deconstruction. The world is on hold until I finish....
I've reverse bled clutches with a goldenrod oil can. It took me a while to find an oil can that pumps positive pressure, but it works fine.
I have a motive bleeder for brakes.
$8.54 @ Tractor Supply got me two 60cc plastic syringes (you have to sign for them) and 10ft. of clear plastic tubing, hope to try it this weekend!
Wow!! Went out to the garage and tried it while waiting for a delivery and it took about 5 minutes to get it set up, pumping and hearing that high pitch pop, pop, pop of tiny bubbles surfacing in the master. So encouraged, I'm going to attack the R-90 that I haven't been able to bleed out and no one wants to work on.
Dan
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