Brake Bleeding...Pressure VS Vacuum and Preferred DIY Kits?

[Donald]

Speed bleeders are awesome

+ 1 - I bought the Motive pressure bleeder and some SpeedBleeders mainly because I wanted SS bleaders. I also bought the little bladder bag from SpeedBleeder for used brake fluid.

The SpeedBleeders were so easy I never used the Motive.

If I was going to use the Motive I would use it for pressure only. Not fill it with brake fluid.

 

[The Critic]

quote " 2018 Toyota RAV4 Gas model. I would also like to exchange all brake fluid and bleed the system"

The only way you will achieve a full exchange of all brake fluid is by using the Toyota Techstream software and perform the ABS brake bleed, ( higher end scanners can do the same) . I have used the software to brake bleed our 2019 highlander and a 2017 Prius.

The software uses the ABS pump to move out all the fluid and re-calibrate the ABS system. It's normal only done by the dealer when they have to replace components of the ABS system.

I highlighted the process here : https://priuschat.com/threads/air-bleeding-with-techstream.244147/ which screen captures of the software. You need helper in the car, how clicks the next, and your under the car cracking open the bleed ports when directed by the software.

View attachment 270157

ABS pump will bleed the rears. Most of the time, conventional methods are still required for the front.

 

[D60]

I hesitate to say this because it's not exactly "DIY" level, but if you ever stumble on a Branick G300, mine has changed my life.

Keep your eyes peeled in whatever classifieds you frequent for keyword "Branick" (and hey, you just might find a killer deal on a spring compressor, too).

Also they seem to retail at ~$400 at Tool Discounter, so they're not that expensive new.

No pumping a glorified garden sprayer, air bladder is separate from fluid, and if you run dry the bladder just fills the whole keg and NOTHING happens.

 

[SoCalAngler]

The pro-level bleeding tools are pressure-bleeders that fill/flush/bleed and even help in testing for leaks. The preferred method.

The fancy ones do have an internal diaphragm to separate the fluid from air, but one isn't going to find that on a DIY-level tool, which more mostly glorified garden sprayers.

I have a Motive, which has a pump to generate pressure, as well as a Gunson, which relied on an external air source (a tire) for pressure, like the Speedibleed.

The Motive is ok, but anyone who has owned a consumer-grade garden sprayer knows that they're not exactly built to last.

In use, I actually preferred the Gunson, which had more, and more consistent pressure from a tire, which is also easier to set, and refill to a preferred PSI level. It consistently filled the reservoir while under pressure, and didn't leave a large air bubble like the Motive does. However, though the principle is sound, the execution and build quality left something to be desired, with leaks at the tire chuck, and the reservoir adapter cap. The dealer was good at support with replacement parts, but fighting the tool got tiresome, which is why I bought the Motive for cheap online when things were still practically being given away to build online commerce.

No matter which style, the most vital part of a pressure bleeder tool is a good adapter cap. That's much easier to achieve with a threaded cap, like the style ATE has been using forever; I'm glad I don't have to deal with any vehicles that have the snap on covers like GM has used in the past, and such.

As far as whether to fill the bottle, in my mind, I'd much rather have the hassle of cleaning the bottle, rather than risk pushing air into the system and having to do the job again, especially if it involves a clutch, which can be more problematic to bleed.

Cleaning the bottle is another task, but again, I'd rather do it right, and start with a clean slate 2-3 years down the line, rather than pour fresh fluid into a container that has remnants of old brake fluid, not from a sealed container, and push that into the system the next time.

If I had to do it now, I'd probably opt for the Speedibleed, and will when the Motive acts up.

I read somewhere that the the idea of pressurized canisters full of brake fluid (Speedi, Motive, etc) is a crazy ridiculous idea! Why…. because using silicone hoses and simple worm gear hose clamps is a catastrophe waiting to happen!!! Think bursting hose spraying brake fluid all over and damaging paint on vehicle along with all vehicles in the same garage or in close proximity!!!
This person decided to use the pressure bleeders without filling canister with fluid…. Simply attach to res and pressurize. Checking res fluid levels frequently.

Perhaps this potential catastrophic event is a reasonable assumption given the hose and screw clamps they use.

Thoughts on this potential for bursting hoses and spraying fluid everywhere?

 

[D60]

I read somewhere that the the idea of pressurized canisters full of brake fluid (Speedi, Motive, etc) is a crazy ridiculous idea! Why…. because using silicone hoses and simple worm gear hose clamps is a catastrophe waiting to happen!!! Think bursting hose spraying brake fluid all over and damaging paint on vehicle along with all vehicles in the same garage or in close proximity!!!
This person decided to use the pressure bleeders without filling canister with fluid…. Simply attach to res and pressurize. Checking res fluid levels frequently.

Perhaps this potential catastrophic event is a reasonable assumption given the hose and screw clamps they use.

Thoughts on this potential for bursting hoses and spraying fluid everywhere?

Much ado over nothing. What do you guys take your Motive to? Usually ~20psi is plenty for my Branick.

But so what? Wipe up the fluid promptly and you're fine.

If using the hook-and-chain universal adapter(s), an initial leak is practically SOP. Close the valve, adjust and try again.

 

[D60]

Also, of all the automotive fluids you could get in your eyes, brake fluid is some of the least concerning. This is NOT to say throw caution to the wind. I always wear eye protection in the shop. But if personal safety is a concern, some brake fluid that might spray in your eyes is not something to stress about -- at least not enough to say lightly pressurized systems should not be used. Changing a fuel pump is far more dangerous.

 

[Carmudgeon]

I read somewhere that the the idea of pressurized canisters full of brake fluid (Speedi, Motive, etc) is a crazy ridiculous idea! Why…. because using silicone hoses and simple worm gear hose clamps is a catastrophe waiting to happen!!! Think bursting hose spraying brake fluid all over and damaging paint on vehicle along with all vehicles in the same garage or in close proximity!!!
This person decided to use the pressure bleeders without filling canister with fluid…. Simply attach to res and pressurize. Checking res fluid levels frequently.

Perhaps this potential catastrophic event is a reasonable assumption given the hose and screw clamps they use.

Thoughts on this potential for bursting hoses and spraying fluid everywhere?

At most, pressures will be in the mid-20 psi range. One is advised to operate the Motive in the mid-teens. These aren't the most robustly constructed things in the world, but if they're blowing hoses off at such low pressures, I wouldn't bother with one to begin with.

And the most likely spot to leak and spray fluid is at the adapter cap to the reservoir, which is pretty obvious and simply acts like an overflowing reservoir. I have had the Motive seep at the fitting between the output hose and the cap pigtail, but I guess I didn't crank it down hard enough. Elsewhere, it will be bleeding air.

Which brings to mind another thing I don't like about the standard Motive bleeder -- there's no pressure release mechanism, except for loosening the pump/cap assembly on the tank. With the Gunson, Speedibleed, or an external-source bleeder, it's easy to release the chuck from the tire, or disconnect the source of pressure. The fancier Motive upgrades the adapter cap to metal with a swivel fitting (another nicety the standard model lacks), but still lacks a pressure release mechanism.

I've been meaning to drill a hole in my Motive's tank, and install a metal Schrader valve stem to allow it to be pressurized with a compressor, and also serve as a release valve, but haven't gotten around to it yet.

Like I said, these DIY-level tools are glorified garden sprayers. It's nice to have a turnkey off-the-shelf product, and credit to those who created a business out of it (and then sold it), but it wouldn't be difficult for those with the initiative to build their own.

 

[D60]

I've often wondered if the Mityvac MV6412 for bottom fill transmissions could be used for brake bleeds.

It's still garden sprayer-esque but seems to be their own proprietary tank more intended for the purpose. It has quick connects and a pressure release bulb.

The main drawback is that it doesn't have any of the master cylinder adapters so you'd have additional expense there. But otherwise I think it'd work great.

 

[PF52]

At most, pressures will be in the mid-20 psi range. One is advised to operate the Motive in the mid-teens.

+2

I'm even more cautious; I don't think I've taken mine above about 10 PSI. The possibility of it "exploding" and spraying brake fluid on adjacent cars is unlikely.

 

[cjcride]

I remember like 20 years ago on here somebody advised against pressure bleeding because the increased pressure would force air to dissolve into the brake fluid.

Don't start that one up again.
I remember one thread about 6 years ago

 

[BobsArmory]

I remember like 20 years ago on here somebody advised against pressure bleeding because the increased pressure would force air to dissolve into the brake fluid.

What do you want to bet that some dealership has advertised a "nitrogen powered brake bleed system" only $499 per service to save your family from complete catastrophe & death .

 

[Chris Meutsch]

I did not know about Speedi-bleed kits. I’ll be getting one of those $82 versions for the 4Runner. Way overdue to replacing that fluid.

 

[The Critic]

I did not know about Speedi-bleed kits. I’ll be getting one of those $82 versions for the 4Runner. Way overdue to replacing that fluid.

On that generation 4Runner you only use the bleeder for the fronts. Rears are bled using the ABS pump.

 

[Chris Meutsch]

1) Speedi-Bleed: https://bobistheoilguy.com/forums/threads/speedi-bleed-pressure-brake-bleeder.376008/

2) Pressure. If you plan on doing more complex repairs, pressure is required to bleed certain ABS modules. Vacuum always leaves some air pockets due to the aeration and you will need to follow up with a manual bleed. Anyone who says otherwise has never done a side-by-side comparison.

3) Ideally, you would want something with a diaphragm that separates the air from contacting the fluid, but those are tough to come by. I prefer shop air.

4) Air compressor, but only if you have a large tan

On that generation 4Runner you only use the bleeder for the fronts. Rears are bled using the ABS pump.

I did learn that info recently. With this kit, couldn’t be easier. TY.

 

[wlk]

I'm not doing brakes every day, but somehow I always end up going back to a rubber hose and a pop bottle.

Been using an old mountain dew 1lt bottle and 1/4" fridge water line method for years, no issues.

 

[wtd]

I read somewhere that the the idea of pressurized canisters full of brake fluid (Speedi, Motive, etc) is a crazy ridiculous idea! Why…. because using silicone hoses and simple worm gear hose clamps is a catastrophe waiting to happen!!! Think bursting hose spraying brake fluid all over and damaging paint on vehicle along with all vehicles in the same garage or in close proximity!!!
This person decided to use the pressure bleeders without filling canister with fluid…. Simply attach to res and pressurize. Checking res fluid levels frequently.

Perhaps this potential catastrophic event is a reasonable assumption given the hose and screw clamps they use.

Thoughts on this potential for bursting hoses and spraying fluid everywhere?

I have the Speedi-bleed and they only recommend about 15 psi and you can even go down to 10 psi and it will still work. They do not use worm style clamps on their hoses. My kit also uses EPDM hoses on both sides of the bottle.

 

[wtd]

How about mentioning the gravity bleed method..

Gravity bleed doesn't always work. I had two instances on two different GM vehicles that after I blew out a rear hard line on both, I could not get the rear bleeders to bleed either by using a vacuum bleeding system or gravity bleeding.

This was before I had my pressure bleeder and the only way I could get fluid out the rear bleeders was the old-fashioned way of having a helper inside the vehicle pushing on the brake pedal to force the fluid down.

 

[researcher]

Gravity bleed doesn't always work. I had two instances on two different GM vehicles that after I blew out a rear hard line on both, I could not get the rear bleeders to bleed either by using a vacuum bleeding system or gravity bleeding.

This was before I had my pressure bleeder and the only way I could get fluid out the rear bleeders was the old-fashioned way of having a helper inside the vehicle pushing on the brake pedal to force the fluid down.

Thanks for the info..