Brake bleeding: pressure or vacuum?

[volodymyr]

Originally Posted By: HTSS_TR


[...]

What bother me the most was I had to remove the wheels to gain access to bleeder valves. Raising the car, placing jack stands, removing the wheels, re-installing the wheels, removing jack stands, lowering the car took too much work and time.


Rear wheels are usually accessible without jacking (depends on a car, mine is an SUV so it is easy). Front wheels are accessible if you turn the wheel to expose the caliper.

 

[Vikas]

Originally Posted By: HTSS_TR
What bother me the most was I had to remove the wheels to gain access to bleeder valves. Raising the car, placing jack stands, removing the wheels, re-installing the wheels, removing jack stands, lowering the car took too much work and time.
Does pressure vs vacuum changes this in anyway?

 

[Joel_MD]

Originally Posted By: volodymyr
Rear wheels are usually accessible without jacking (depends on a car, mine is an SUV so it is easy). Front wheels are accessible if you turn the wheel to expose the caliper.

Calipers get exposed when you turn the steering wheel? What kind of car do you have in which the caliper does not turn with the wheel?

 

[supton]

I did this job a month or two ago. Was real easy when I had the car completely on jackstands and doing a tire rotation at the same time too. Remove and inspect pads, lube everything up, change brake fluid, rotate tires, done. Actually I did oil changes at the same time too.

Might as well kill the afternoon and do everything at once.

 

[HTSS_TR]

Originally Posted By: The Critic
Vacuum bleeding (using mityvac or vacula) has been problematic for me - usually the pedal will be a bit softer after you're finished due to a small amount of air that is let in. I've noticed this on cars that come from other shops that also vacuum bleed.

I don't think it's possible to have any air get in the system, especially via the bleeder valve, as long as you don't let the reservoir empty.

Originally Posted By: volodymyr
Rear wheels are usually accessible without jacking (depends on a car, mine is an SUV so it is easy). Front wheels are accessible if you turn the wheel to expose the caliper.

It isn't possible to gain access to bleeder valves for the S2000 without jack it up.

Originally Posted By: Vikas
Does pressure vs vacuum changes this in anyway?

No, neither method changes the problem of raising the car. What I mean was the actual brake bleeding work with Mityvac is very easy/simple and fast. It was done in less than 10 minutes max, but the time I spent raising the car, remove the wheels, reinstall the wheels and lowering the car was about 1 hour. Too much time and work to prepare for actual job.

I had Motive pressure bleeder some years ago, it didn't work well on my LS400 and E430. I already had the Mityvac to do oil change for my E430, why not use it to do other tasks for all cars such as ATF and brake bleeding ?

I used Mityvac 7201 to bleed the brake systems in all my cars more than once for each car the last 6-7 years. It worked so well for all cars, much better than Motive pressure bleeder.

I rather have 1 tool that can do several jobs well than multiple tools and each tool can only do 1 job.

Originally Posted By: supton
I did this job a month or two ago. Was real easy when I had the car completely on jackstands and doing a tire rotation at the same time too. Remove and inspect pads, lube everything up, change brake fluid, rotate tires, done. Actually I did oil changes at the same time too.

Might as well kill the afternoon and do everything at once.

Do everything all at once is a good idea. Raising the car and removing the wheels and do all maintenance in 1 shot and don't bother with jacking the car up for another 2-3 years.

 

[Bgallagher]

Originally Posted By: supton
I did this job a month or two ago. Was real easy when I had the car completely on jackstands and doing a tire rotation at the same time too. Remove and inspect pads, lube everything up, change brake fluid, rotate tires, done. Actually I did oil changes at the same time too.

Might as well kill the afternoon and do everything at once.


Sounds like a nice little afternoon to me.

 

[volodymyr]

Originally Posted By: Bgallagher
Originally Posted By: supton
I did this job a month or two ago. Was real easy when I had the car completely on jackstands and doing a tire rotation at the same time too. Remove and inspect pads, lube everything up, change brake fluid, rotate tires, done. Actually I did oil changes at the same time too.

Might as well kill the afternoon and do everything at once.


Sounds like a nice little afternoon to me.


+1 ... I actually bought pressure bleeder because I thought it will make flushing the brake fluid easy job so that I can do this every November when switching to winter tires.

 

[HerrStig]

Originally Posted By: Joel_MD
Originally Posted By: volodymyr
Rear wheels are usually accessible without jacking (depends on a car, mine is an SUV so it is easy). Front wheels are accessible if you turn the wheel to expose the caliper.

Calipers get exposed when you turn the steering wheel? What kind of car do you have in which the caliper does not turn with the wheel?
If the nipple is on the top of the calpier and the wheel is turned hard over, you can get to it inmany applications. Lots of Toyota products are like that. Doesn't help for the rears, though.

 

[volodymyr]

Originally Posted By: HerrStig

[...]

If the nipple is on the top of the calpier and the wheel is turned hard over, you can get to it inmany applications. Lots of Toyota products are like that. Doesn't help for the rears, though.



Yes, if a car has short rear boot (which seems to be my case) you can access the rear wheels easily. I will try to make some pictures next time I will do this (I do not promise, but I will try).

 

[cjcride]

Flushing every 2 years is fine. Make sure the reservoir is topped up with fresh fluid and pump to about 12 PSI. Works every time.

 

[supton]

Quote:

Do everything all at once is a good idea. Raising the car and removing the wheels and do all maintenance in 1 shot and don't bother with jacking the car up for another 2-3 years.


Well, like about ten times a year, give or take...

(Every 5k. One car is driven at 25k/year, another is upwards of 20, the last is 5.)

 

[slipstream444]

I've used vacuum, gravity, pressure and reverse fluid injection on several cars over the years. The method that seems to work 98% of the time on almost every vehicle - is gravity... but it takes a long time. The least successful in my experience is vacuum bleeding.

Using a pressure bleeder requires a little more setup time to get it right, but it seems to overall be the fastest and will work every time, as long as the setup is perfect. It can also be the messiest depending on what car you are doing this on - and how good the master cylinder adapter is. There are no reliable master cylinder adapters for the S2000, so you have to use a messy universal type - which (you guessed it) guarantees a mess. There are several for my E90 335d, and it's a snap. My older (now gone) VW Sportwagons were equally easy to do.

Reverse fluid injection is a relatively novel approach for the consumer level automotive market. I've used the Phoenix hand held system (middle of the line system) and it just created bubbles and aggravation. Nevertheless, the procedure is used in aircraft and some race car systems, so I decided to try the procedure using a slightly modified conventional power bleeder. It works, and can be used in lieu of a full bench bleeding of a new master cylinder on the car as well. The method forces fluid into the braking system at the caliper bleeder (or the ABS module, or at the ports on a new master cylinder - but this method will obviously not work with speed bleeders) The fluid (and air) is forced back into the master cylinder reservoir where air bubbles are released. Some important notes to this method: this method is best used if you are installing new and internally clean components. This also may be the best last resort if you have tried every method and can't get the air out. The RFI method will chase all the air out. If you want to use this method on old or existing brakes - it is HIGHLY recommended to use another method first to ensure the majority of the fluid in the system is clean - because you don't want to push dirty caliper nastiness back into the master cylinder.

A last note on bleeding order: not every car uses the furthest brake first method. A great example is the Honda S2000. You do the closest (front left for USDM), the other front brake, then cross to the rear brake behind the first brake, then the furthest is last. Check your service manual first.

In all honesty, if you are using the pressure method and hitting every corner more than twice - I don't think it really matters.

 

[mightymousetech]

I always use the vacuum bleed method, then while the corner is under vacuum, I will pump the brake pedal 10 times, just a nice even push, not too fast, not too slow, with a small pause at the top. Take vacuum hose off the bleeder, then let it drip for a while until the bubbles have stopped, which is normally only a couple seconds. Vacuum bleeding will usually pull a couple bubbles of air past the threads. Then just tighten up the bleeder. When done, give the pedal a couple nice hard pushes to get everything seated again.

Has always resulted in a very firm brake pedal, and I do 5 or 6 a week.

The order you do the corners in makes absolutely no difference.

 

[andyd]

I don't do brakes enough to invest in equipment to work on them. If you can't get a gravity bleed going, then there is a leak. So it checks my work. I also set up air locks using small jars of BF and tubing on the bleeders. I used some old vacuum hoses and bleed both rears at once. I pump the pedal by hand so I can watch for bubbles. Low tech all the way. I'm not into car fixing on a professional basis either, though.

 

[BrianF]

I use the one man pressure bleed. Pop bottle, some clear tube and a small zip tie. Amazingly simple and works great.

 

[BigD1]

Bought a Harbor Freight pneumatic bleeder, and I will never go back to gravity or two man. Made in Taiwan, and the kit seems to be made good, and it worked just fine for me. Costs about $27 plus tax out the door depending on what coupon is used. https://www.harborfreight.com/brake-fluid-bleeder-92924.html

Not all cars/trucks go by the standard rear right and rear left, and etc. brake bleeding order. My Toyota pickup starts at rear left, and then to the rear right. My Volvo 240 has multiple bleeders, and I would have look at my notes to find the correct bleed procedure, but it's nothing like the standard procedure.

 

[Yah-Tah-Hey]

Russell Speed Bleeders. No more asking war department to help bleed the brakes.