Resolved Can you vacuum bleed M/C instead of bench bleeding?

[kendawg73]

So all my brake components are new, SS, lines, wheel cyc, calibers etc... Can I bolt the New M/C on, and just vacuum bleed the system? I didn't want to bench bleed it, since the chance of getting brake fluid spilled in the engine bay will surely happen when I plug the plugs hoses and try to hook up the lines etc..

So, I was just hoping I can just hook everything up and vacuum bled the system. To me it would seem that it should work but wanted to check with everyone first.

 

[AeroCoupe]

MC installs at an angle so it makes getting the air out a pain when installed. If you can jack the rear of the car up so that the MC is level then that may work. Once you have the MC bled then you can let the back of the car down and continue bleeding the brakes.

I bench bleed the MC and use absorbent pads in the engine bay to keep the fluid from getting on the car. Typically not much comes out as the lid on the reservoir keeps it from free flowing. Think of filling a straw with water and then putting your thumb over the end and no liquid comes out. Has to do with the liquid specific gravity, atmospheric pressure, and liquid column height. Anyhow, this method works good for me.

 

[limp]

Typically not much comes out as the lid on the reservoir keeps it from free flowing.

This......
Are all of the rubber parts new? Use Dot 5.... It does not harm paint...

 

[MustangIIMatt]

Can I Use DOT 5 Brake Fluid With My New Brake Kit? | Master Power Brakes

Some of you are asking the same question, so this post is designed to clear up confusion about the different types of brake fluid.

techtalk.mpbrakes.com

Don't use DOT5.

 

[limp]

Can I Use DOT 5 Brake Fluid With My New Brake Kit? | Master Power Brakes

Some of you are asking the same question, so this post is designed to clear up confusion about the different types of brake fluid.

techtalk.mpbrakes.com

Don't use DOT5.

I have used DOT5 for over 40 years and never had a problem with it.... As a matter of fact it has made the projects go easier with no problems worrying about nasty brake fluid ruining a paint job.....

 

[General karthief]

I have used DOT5 for over 40 years and never had a problem with it.... As a matter of fact it has made the projects go easier with no problems worrying about nasty brake fluid ruining a paint job.....

You are a lucky dog

 

[AeroCoupe]

Regardless of what type of brake fluid you use just make sure it fits the application. I stay away from DOT 5 in my Coupe due to the ABS system as it is not recommended. You can use it in an ABS system but it can aerate due to the action of the piston in the ABS pump which is no bueno. DOT 4 and DOT 5.1 are recommended for ABS vehicles due to the lower viscosity than DOT 3.

DOT 3 is what our cars came with but I would say that DOT 4 is becoming if not is the most commonly used brake fluid in cars on the road today due to ABS systems. DOT 4 is compatible with DOT 3 but I would highly recommend flushing the system completely with DOT 4 and not just topping off if you are going to make that move. You should not top off a brake system with a lower DOT fluid that what is already in there. This is due to the system is engineered based on the properties of the fluid and by introducing a fluid that has a lower boiling point and higher viscosity it will alter the braking performance.

Here are a couple really good writeup on the differences and uses of the DOT brake fluids:

DOT 3 and DOT 4 Brake Fluid: What's the Difference? - AMSOIL Blog

The real difference between DOT 3 and DOT 4 are their boiling points, which are narrowed to dry and wet boiling points. Do you know the difference?

blog.amsoil.com

What Type of Brake Fluid Do I Need? | PowerStop

Different types of brake fluid are used for different reasons. It's important to know which one to use for your vehicle when upgrading your brakes.

www.powerstop.com

Vehicle Maintenance: Brake Fluid DOT 3, DOT 4, DOT 5.1, and DOT 5 - Valvoline™ Global Europe - EN

Brake fluid selection is a particularly important task of vehicle maintenance. Different types of brake fluids match the requirements of specific braking systems. The most common ones used today are DOT 3, DOT 4, DOT 5, and DOT 5.1 brake fluids. Are all brake fluids the same? If not, what is the...

www.valvolineglobal.com

Just to clarify, I know ABS did not come factory in any Fox Body Mustang. The one in my Coupe is out of a 95 GT car and I was the one who installed it based on a writeup that an engineer from Ford did when he installed it in his Fox Body.

 

[limp]

You are a lucky dog

Nah, Bentley is the lucky dog......

 

[limp]

You are correct, no dot 5 in an ABS system....

 

[General karthief]

Nah, Bentley is the lucky dog......

He ain't that lucky.
He has to hang with you

 

[96pushrod]

I’ve never tried using a vacuum bleeder without bench bleeding.

However, I’ve done master cylinders and used my pressure bleeder to bleed the system and not bench bled the master.

 

[limp]

However, I’ve done master cylinders and used my pressure bleeder to bleed the system and not bench bled the master.

Thats an interesting concept... I will have to try that......

 

[Mr.Kelley]

To answer the original question, no. There is some magic that happens when you push the MC piston all the way to the end of the bore that no other method can do. You can't get there with the MC mounted.

 

[Mustang5L5]

You can do it if you are able to jack the rear of the car up far enough to level it. Just be warned, you need to get it pretty high and it may not be safe. But MC needs to be level and it would be beneficial if the outlet ports are tilted higher, meaning the pass side needs to be higher.

Given the extreme angles, it's going to be somewhat precarious, hence the recommendation to just remove and bench bleed.

 

[96pushrod]

https://www.summitracing.com/parts/mvp-0107

Get one of these and you’ll never bench bleed again. Or need a second person to help manually bleed.

 

[AeroCoupe]

Motive for the win. Makes bleeding ABS systems sooo much easier and like 96pushrod said no more yelling into the house for an assistant. They offer all kinds of different adapters which comes in handy if for some awful reason you don't own anything but a Ford...ha ha ha!!!

 

[Mustang5L5]

I dislike my motive. It sits gathering dust and I just do a one-man method that has worked well for me.