Anyone tried one of the reverse brake bleeders? It pushes fluid back from the caliper to the master rather than drawing the fluid from the master through the caliper.
I'm pretty sure I've got some air in the clutch assembly and perhaps some in the brakes as well (little soft last race). I've used the vac type system (pump it up and suck the fluid out) but do both by myself so some sort of one man operation is needed. I can't always get Rob Poma to come sit in the car!
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Sean O'Connell
1996 RF96 FC
1996 RF96 FB
2004 Mygale SJ04 Zetec
if you have a design flaw in the way your calipers, slave cylinder etc are laid out, the reverse bleeding really won't help all that much with entrapped air bubbles. If you don't plain old bleeding works fine. Sometimes you have to take the calipers off and rotate them around a bit to chase the last bit of air up to the bleed screw. Old style MK9 clutch slave cylinders on the side of the box are notorious for that, the slave cylinder is mounted at 90 degrees from how it was designed to be mounted.
I feel that reverse bleeders that push from the caliper are better than vacuum ones that suck from the master cylinder, but then again I use neither. The only car I couldn't get to bleed easily was a 1958 bugeye sprite with all drum brakes...
I agree with Rick. Speed Bleeders. Not needed on the clutch. With a long enough tube it's easy to depress the pedal slowly, let it back and then just close the bleeder with fluid still in the tube. One possible issue on the clutch is improper routing of the lines to and from the slave which allows for capturing air in a high spot either in one of the lines or the slave itself. Just a thought.
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Charlie Warner fatto gatto racing
I use a speed bleeder near the slave cylinder and an adjustable bar clamp at the pedal. Pump clutch in normal manner with speed bleeder open. Also start with speed bleeder closed, depress clutch with bar clamp and go to back to open speed bleeder.
This winter I did use a vacuum bleeder to pull fluid into a dry rear brake line before normal speed bleeder brake bleeding would work.
Flushed the brake fluid in a street car this weekend by myself thanks to speed bleeders. Best invention ever for the "do it by myself" guy.
Sean,
After many years, I finally fixed the bleeding alone problem. I'm sure you have an air compressor at home... take a spare master cylinder cap and drill a hole through it and epoxy in an air nipple. Screw on the nipple cap onto the cylinder and cut down the air compressor output valve to about 3-5 psi. Stick the air hose on the nipple and go bleed.
Except if your doing this solo, the clutch takes a good bit of force- no way your doing it by hand. I believe the lines are all properly routed- likely have moisture in the fluid as it's been in there a while. I may use my mityvac to suck the old fluid out and then reverse bleed the system once new fluid is comming out...
Quote:
Originally Posted by Charles Warner
I agree with Rick. Speed Bleeders. Not needed on the clutch. With a long enough tube it's easy to depress the pedal slowly, let it back and then just close the bleeder with fluid still in the tube. One possible issue on the clutch is improper routing of the lines to and from the slave which allows for capturing air in a high spot either in one of the lines or the slave itself. Just a thought.
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Sean O'Connell
1996 RF96 FC
1996 RF96 FB
2004 Mygale SJ04 Zetec
I honestly don't understand this "bleeding alone problem". I've bled many many cars alone, and all I use is a jar and a piece of hose. I put the hose so that there is a loop above the bleed screw so there is always a "head" of fluid above the screw, I put a little light smear of grease on the bleed screw threads so that there is no leakage of air past the threads, and I slowly pump the pedal leaving the bleed screw open. You do it slow enough, you get all the air out within a dozen or so pumps even from a new dry system. You start with the longest line and go to the shortest line. You make sure, as I noted above, that your calipers etc have the bleed screw at the very top while bleeding even if you have to take the caliper off temporarily. Obviously you top up the master cylinder as needed. So far this is a never fail method, so I don't understand the issue...
Except if your doing this solo, the clutch takes a good bit of force- no way your doing it by hand.
If the bleeder is open you should be able to easily depress the clutch pedal by hand. If you can't you have other issues. It should be easier than depressing the brake pedal while bleeding.
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Charlie Warner fatto gatto racing
I, like Brian, have done this by myself for many years. Yes, it's easier with someone in the car (maybe I just feel more confident), but not impossible to get all the air out yourself.
I haven't tried the grease to the bleeder threads trick.
I've changed over to solo-bleeders on some and that helps ease the job.
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Keith
Averill Racing Stuff, Inc. www.racing-stuff.com
248-585-9139
The only "trick" to keith's and my method is low and slow, it that qualifies as a trick. No pump it up and crack the bleed screw, no pump five times fast and tighten the bleed screw, just pump in and out slowly, pause between strokes for a second. Zen-like. Have "ocean sounds" playing on the shop stereo. Have the loop of tube higher than the bleed screw and no air can back-feed.
Edit - I did forget to say that you use transparent hose so you can see the bubbles, but all the brake bleed kits I've got came with transparent hose anyway.
The only "trick" to keith's and my method is low and slow, it that qualifies as a trick. No pump it up and crack the bleed screw, no pump five times fast and tighten the bleed screw, just pump in and out slowly, pause between strokes for a second. Zen-like. Have "ocean sounds" playing on the shop stereo. Have the loop of tube higher than the bleed screw and no air can back-feed.
Edit - I did forget to say that you use transparent hose so you can see the bubbles, but all the brake bleed kits I've got came with transparent hose anyway.
Brian
Another vote for this method, has always worked for me.
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Scott Woodruff
83 RT5 Ralt/Scooteria Suzuki Formula S
65 FFR Cobra Roadster 4.6 DOHC
Another trick (I first saw years ago in the Bryar Motorsports Park rocky paddock) is to tap the caliper with a hammer to dislodge air bubbles. I don't know if it really works but I do it.
Yea Brian has it right...done it for years except I put a hole in a jar, right size squish on tubing (no air, no clamp, squish on, do yourself a favor and go to hardware store and get a few feet of all sizes, clear stuff ok, rinse with H2O after use or gets hard) and get a step stool,
the physics part comes in when u race tape the jar to the step stool and all of the line is above the bleeder...... I do an alternate trick on bleeder and put a small amount of teflon tape as opposed to Bri's grease, same deal.......works with one user up front at the reservoirs to fill, must observe bubbles in line or line in general (sometimes no bubbles and what the hell did you worry about it in the first place, get stuff dirty, ANYWAY) close the bleeder and sometimes for good luck will get someone at track or my wife in garage to hit pedal once and open-close in case teflon-grease did not work and bubble sitting at bleeder ready for expellation (is that a word??), never a problem and with FC or lower u would be wasting your money constently buying fluid so there is no moisture...hell it has a breather hole exposed to air anyway talk about moisture......and the cars are way lighter than a road car, brake in two seconds (don't think we are going to 470 degrees (whoops 212F) or higher in two seconds......ok 3.5 seconds.......road manufacturers don't worry 'bout moisture good stuff Brian.........
one other note: only time I had a problem with the brakes is from not watching the less used rear pads and they got low....had squishy pedal that can be a little disconcerting going into the boot, eye on them is in order!! well ok, another, don't mix pad compounds unless you can thouroughly test that nasty idea!!
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Mike O- Summit,Glen,Rd Atlanta,Rd America,Brainerd, Bryar,LimeRock,New Jersey MP,Trenton,Phoenix,Charlotte, Vir,Mid Ohio,Riverside,Buttonwillow,Vegas,Nelson,Pocono,
West Palm,Mosport,Mt Tremblan,Bridgehampton,Heartland
Last edited by Modo; August 16th, 2011 at 3:41 PM.
One thing noone has mentioned is bleeding the master cylinder. Always do this first. And have the car slightly nose up to force any air in the master cylinder towards the front/higher part (you can tap the side gently if you choose.) Wrap a rag around the fitting, hold slight pressure on the pedal with your hand and crack the fitting until you feel the pedal start to move. Tighten fitting and clean up. THEN bleed the rest of the system.
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Charlie Warner fatto gatto racing
Most if not all of the car manufacturers (of road cars) now specify changing the brake fluid every two years on cars with ABS/TC. The control units have very tiny holes that can easily become plugged with contaminates from "dirty, moisture laden" brake fluid.
For that reason, I dislike the thought of pushing that old brake fluid back into the m/c, especially on a road car with ABS/TC. All the "old" brake fluid goes through the control units. In fact, one service manual stated that when installing new pads, one should open the bleed screws so as not to push the old fluid into the control units while pushing the pistons back.
I use the clear tubing above the bleed screw technique myself.
dave
I honestly don't understand this "bleeding alone problem". I've bled many many cars alone, and all I use is a jar and a piece of hose. I put the hose so that there is a loop above the bleed screw so there is always a "head" of fluid above the screw, I put a little light smear of grease on the bleed screw threads so that there is no leakage of air past the threads, and I slowly pump the pedal leaving the bleed screw open. You do it slow enough, you get all the air out within a dozen or so pumps even from a new dry system. You start with the longest line and go to the shortest line. You make sure, as I noted above, that your calipers etc have the bleed screw at the very top while bleeding even if you have to take the caliper off temporarily. Obviously you top up the master cylinder as needed. So far this is a never fail method, so I don't understand the issue...
The reverse bleeders in my mind just push the nasty overheated fluid into your master then what do you do?
I have done the method that Brian stated for years on many types of cars, race cars, motorcycles and Karts it never fails it always works and you can do it alone. Key is to put something on the bleeder to stop air leaks like he said. I have put liquid thread tape on the bleeder before I put it in and it makes a pretty good seal.
The grease on the threads with the vacum bleeder works best with "syl glyde" grease.
About 8 bucks at most real parts stores like NAPA for a tube that should last the average person about 20 years. It is neat cause it is compatible with brake fluid and will not run at high temps as well.
Make sure to use a rubber or plastic hammer to rap on the calipers with.
The grease on the threads with the vacum bleeder works best with "syl glyde" grease.
About 8 bucks at most real parts stores like NAPA for a tube that should last the average person about 20 years. It is neat cause it is compatible with brake fluid and will not run at high temps as well.
Make sure to use a rubber or plastic hammer to rap on the calipers with.
Their sealant works on the threads of speed bleeders. I assume it would work on normal bleeders also and wouldn't need replacement as often as grease may.
The reverse bleeders in my mind just push the nasty overheated fluid into your master then what do you do?
If you have any overheated fluid (nasty or otherwise) in your system you have to flush the entire system and refill with fluid that won't overheat under the conditions. Once fluid is overheated it becomes useless and will contaminate the rest of the system.
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Charlie Warner fatto gatto racing
exactly right, Charles. I am so not a fan of fads and overly complicated ways to accomplish simple tasks. Although our mutual friend Derek H. often comes up with elegant, complicated ways to perfectly accomplish otherwise simple tasks, including at times asking me to do them... sorry to everyone else on this channel, I just happened to read this and think of Derek for some reason.
Brian
I believe I inadvertently cast an aspersion towards my friend Derek. Here is the explanation I sent him, in clarification. My profound apologies are well in order.
[FONT=Arial][SIZE=2][FONT=Arial]I love the solutions you come up with. Your engineering mind is so much better than mine at creating things, they are all over everything you do. Elegant, to my mind complicated, but more effective than my simple ways. I had in mind several specific things, like the adaptors you built for your starter motor, I think the coolant adaptor for the Buick, the stand system that you built for your cars to roll around on, etc. I was very impressed with the model you built for me to copy when I made the engine adaptor. You build a shelf system to organize and carry things in your trailer, I put bins on the floor. That train of thought made me think of you, basically, and it had absolutely nothing to do with bleeding brakes. I can see where you might misinterpret, so I apologize if I took you aback. I was very proud of the engine adaptor I made for you, btw, but I would never have created the model that you did. To me, you are a real engineer – things you do solve several or many problems at once – so to me, complex. Things I do are more linear, I tend to solve only one problem at a time. I hope you still like me…[/FONT][/SIZE][/FONT]
Last edited by Brian; August 17th, 2011 at 9:31 AM.
Reason: fix a mistake
Yes, the jar and the hose. Actually, a can of brake fluid and a hose. Works perfectly, every time. Put the jar/can on a three step ladder, right next to the caliper, so your clear hose is only about six inches long. I've never had anyone help me bleed brakes.
Like the long broomstick Davecad.....been there done that....usually grab the neareast thing....oh no.....it's my tryed and true level!!...don't think the ladder would fit in the Tatuuus!!!
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Mike O- Summit,Glen,Rd Atlanta,Rd America,Brainerd, Bryar,LimeRock,New Jersey MP,Trenton,Phoenix,Charlotte, Vir,Mid Ohio,Riverside,Buttonwillow,Vegas,Nelson,Pocono,
West Palm,Mosport,Mt Tremblan,Bridgehampton,Heartland
Last edited by Modo; August 18th, 2011 at 11:17 AM.
Reason: o
General Formula Car Discussion
Reverse bleeding?
