Vacuum Tester to bleed brakes
- Thread starter Spetz
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I reckon they'd do the job. Just realise that bubbles leaving the bleed screw are likely to be sucked in around the thread under vacuum rather than bubbles in the system, so don't keep sucking trying to get rid of the bubbles.
I use a pressure bleeder these days, but horses for courses.
I use a pressure bleeder these days, but horses for courses.
I dunno how well it works. I could use the tubing and the container to rig a gravity bleed. I could also use the same to rig an air lock for a pressure bleed. Adding a little suction is no big deal.
The whole deal with brake bleeding is to monitor the fluid level in the MC. Keep the fluid above the cylinder port and all is well. If a system is open on top and bottom, and tight in between, it will drain. You don't need pressure or vacuum to drain your bath tub. Gravity works great
The whole deal with brake bleeding is to monitor the fluid level in the MC. Keep the fluid above the cylinder port and all is well. If a system is open on top and bottom, and tight in between, it will drain. You don't need pressure or vacuum to drain your bath tub. Gravity works great
Originally Posted By: Brad_C
I reckon they'd do the job. Just realise that bubbles leaving the bleed screw are likely to be sucked in around the thread under vacuum rather than bubbles in the system, so don't keep sucking trying to get rid of the bubbles.
This. You would waste a lot of fluid if you didn't know that.
I reckon they'd do the job. Just realise that bubbles leaving the bleed screw are likely to be sucked in around the thread under vacuum rather than bubbles in the system, so don't keep sucking trying to get rid of the bubbles.
This. You would waste a lot of fluid if you didn't know that.
And how much fluid is there roughly between the master cylinder and the caliper itself?
Seeing as the container is 120ml, I would assume that the rears should get 2-3 containers full, and the fronts 1-2 containers full?
So close to a quart for the whole brake system?
Seeing as the container is 120ml, I would assume that the rears should get 2-3 containers full, and the fronts 1-2 containers full?
So close to a quart for the whole brake system?
the built-in container should be enough for each wheel i.e. as long as you empty it after each wheel, you should never have to worry about overfilling it.
how in the world do you keep the container vertical if you are not holding everything yourself?
how in the world do you keep the container vertical if you are not holding everything yourself?
See if your car will gravity bleed, most do but a few wont without a little prompting with a little vacuum or pressure. Once it starts dripping just keep the MC full and let it run until clear then lock the bleeder and move on to the next one.
If you didn't open any lines then there is no particular order to do this.
If your having an air problem just tap each caliper with a mallet a few times while the screw is open and dripping.
If you didn't open any lines then there is no particular order to do this.
If your having an air problem just tap each caliper with a mallet a few times while the screw is open and dripping.
Originally Posted By: Vikas
the built-in container should be enough for each wheel i.e. as long as you empty it after each wheel, you should never have to worry about overfilling it.
how in the world do you keep the container vertical if you are not holding everything yourself?
Good observation. I use an old soup tin, rinse it out and stand the tall thin plastic reservoir in the tin can. It still tries to tip but can't.
the built-in container should be enough for each wheel i.e. as long as you empty it after each wheel, you should never have to worry about overfilling it.
how in the world do you keep the container vertical if you are not holding everything yourself?
Good observation. I use an old soup tin, rinse it out and stand the tall thin plastic reservoir in the tin can. It still tries to tip but can't.
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I've used that before. It takes a LONG time to work, and hands get tired after the second wheel. It'll get the job done with one person. There are other tools I'd use before that, however.
why can't one combine this tool with the one man bleeding approach? i.e. make sure the container has enough brake fluid to submerge the tube going to the caliper; apply vacuum; make sure the contraption stays vertical; open the bleeder slightly; press the brake pedal by hand few times; come back and check until incoming tube has clear fluid; close the bleeder; dump most but not all the old fluid; repeat for the next wheel.
In theory, this gets you the best of both methods and should be lot quicker and more thorough.
Comments?
In theory, this gets you the best of both methods and should be lot quicker and more thorough.
Comments?
My mechanic has this tool, it didn't work on the rear of some cars.
I have Mityvac MV7201, it works for all cars front and rear. I bought it to do oil change for E430, I then used it to do ATF, bleed brake ...
I think Mityvac MV7201 is 1 of the best tools to extract/siphon any fluid. It is a little expensive at around $90-100(I bought it more than 10 years ago for $60-70), but it can be used for many different jobs so the return of investment is much better than others.
I have Mityvac MV7201, it works for all cars front and rear. I bought it to do oil change for E430, I then used it to do ATF, bleed brake ...
I think Mityvac MV7201 is 1 of the best tools to extract/siphon any fluid. It is a little expensive at around $90-100(I bought it more than 10 years ago for $60-70), but it can be used for many different jobs so the return of investment is much better than others.
I use this with an auto filler when I do brakes at home. The auto filler holds a couple pints of fluid and I can set it at whatever level I want in the master reservoir.
Originally Posted By: sciphi
I've used that before. It takes a LONG time to work, and hands get tired after the second wheel. It'll get the job done with one person. There are other tools I'd use before that, however.
Remove bleed valve, wrap threads with a couple layers of Teflon tape, reinstall... The tape will lessen vac leak around threads, bleeding goes 10x quicker...
As others have mentioned I'll usually gravity bleed but doesn't work on all cars with ABS...
Originally Posted By: HTSS_TR
My mechanic has this tool, it didn't work on the rear of some cars.
So what's the difference??? Vacuum is vacuum.. Possibly quality of adapters??...
I've used that before. It takes a LONG time to work, and hands get tired after the second wheel. It'll get the job done with one person. There are other tools I'd use before that, however.
Remove bleed valve, wrap threads with a couple layers of Teflon tape, reinstall... The tape will lessen vac leak around threads, bleeding goes 10x quicker...
As others have mentioned I'll usually gravity bleed but doesn't work on all cars with ABS...
Originally Posted By: HTSS_TR
My mechanic has this tool, it didn't work on the rear of some cars.
So what's the difference??? Vacuum is vacuum.. Possibly quality of adapters??...
Originally Posted By: Vikas
Quote:
Remove bleed valve, wrap threads with a couple layers of Teflon tape, reinstall...
By doing that, do you introduce air in the system? I do not know the answer.
I assume you mean is it possible for air to enter through the removed valve??? No, fluid will still gravity bleed through the system and even if it could, you'd be pulling the air out when operating the pump...
BTW space the tape back a couple threads so it doesn't make reinstalling valve difficult... Can leave it in place when finished or remove it, doesn't really matter...
Quote:
Remove bleed valve, wrap threads with a couple layers of Teflon tape, reinstall...
By doing that, do you introduce air in the system? I do not know the answer.
I assume you mean is it possible for air to enter through the removed valve??? No, fluid will still gravity bleed through the system and even if it could, you'd be pulling the air out when operating the pump...
BTW space the tape back a couple threads so it doesn't make reinstalling valve difficult... Can leave it in place when finished or remove it, doesn't really matter...
I used it on my motorcycle only until I accidentally pumped a little bit of brake fluid into the pump.
Since that time it stopped maintaining the pressure and now I only use it to remove the old fluid from the reservoir
Even on motorcycle it took a lot of pumping to suck the fluid out. Also, because the air is sucked in via bleeder threads you really do not know if you have air in the system or not.
Since that time it stopped maintaining the pressure and now I only use it to remove the old fluid from the reservoir
Even on motorcycle it took a lot of pumping to suck the fluid out. Also, because the air is sucked in via bleeder threads you really do not know if you have air in the system or not.
Originally Posted By: TFB1
Remove bleed valve, wrap threads with a couple layers of Teflon tape, reinstall... The tape will lessen vac leak around threads, bleeding goes 10x quicker...
As others have mentioned I'll usually gravity bleed but doesn't work on all cars with ABS...
It is very simple with Mityvac 7201, I just connect a hose to bleeder valve first, pump the Mityvac 4-5 times then loosen the bleeder valve by 1 turn. After bleeding is done close bleeder valve first then remove the hose.
Note: keep reservoir full while Mityvac 7201 extracts brake fluid, 2 full reservoirs for rear and 1 for front.
Originally Posted By: HTSS_TR
My mechanic has this tool, it didn't work on the rear of some cars.
Originally Posted By: TFB1
So what's the difference??? Vacuum is vacuum.. Possibly quality of adapters??...
Vacuum of this kit is not adequate to extract brake fluid from rear wheels, it is okay for front wheels of LS400 and E430.
In my case, Mityvac 7201 is the best solution for more than 1 use. I bought it for changing oil in E430, since the cartridge oil filter is on top of the engine I can get the job done without getting under the car. I then use it for ATF and finally for brake bleed.
One tool to do 3 jobs is better than 1 tool for each job.
Remove bleed valve, wrap threads with a couple layers of Teflon tape, reinstall... The tape will lessen vac leak around threads, bleeding goes 10x quicker...
As others have mentioned I'll usually gravity bleed but doesn't work on all cars with ABS...
It is very simple with Mityvac 7201, I just connect a hose to bleeder valve first, pump the Mityvac 4-5 times then loosen the bleeder valve by 1 turn. After bleeding is done close bleeder valve first then remove the hose.
Note: keep reservoir full while Mityvac 7201 extracts brake fluid, 2 full reservoirs for rear and 1 for front.
Originally Posted By: HTSS_TR
My mechanic has this tool, it didn't work on the rear of some cars.
Originally Posted By: TFB1
So what's the difference??? Vacuum is vacuum.. Possibly quality of adapters??...
Vacuum of this kit is not adequate to extract brake fluid from rear wheels, it is okay for front wheels of LS400 and E430.
In my case, Mityvac 7201 is the best solution for more than 1 use. I bought it for changing oil in E430, since the cartridge oil filter is on top of the engine I can get the job done without getting under the car. I then use it for ATF and finally for brake bleed.
One tool to do 3 jobs is better than 1 tool for each job.
http://www.matcotools.com/catalog/product/MV6832/CLAMP-ON-AUTO-REFILL-KIT/
If you use this, you should never run the master dry.
If you use this, you should never run the master dry.
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