Bleeding Brakes

This question only applies to OR and pro trims only (the system is different). I just saw the new video dropped by Team Oil drop. The video informs the proper way of bleeding the brake system using a scan tool. It shared that some have had issues bleeding the brakes with out it.
Has anyone done this job with out the scan tool. How did you do it? Any issues?

 

You don’t need a scan tool for bleeding the wheel brakes. I checked out the video and he references that for bleeding the master cylinder, which is correct….if you need to bleed the master cylinder. You don’t need to bleed the master cylinder if you don’t have air trapped in it, which you shouldn’t. A typical maintenance brake bleed is done at the wheels only just to get old fluid out and new fluid in. Don’t let the reservoir run low and you won’t need any scan tools.

The FSM is posted below and lines out what to do for a typical wheel brake bleed. It tells you to turn the key to ignition and then pretty much you bleed the fronts like any normal vehicle. Pedal down, bleeder loosened, bleeder tightened, pedal up. Rinse and repeat until no air.

The rears are run by a pump on the hydraulic booster, so you can turn on the ignition, hit the pedal, open the bleeder and it will just pump brake fluid continuously until you tighten the bleeder. So you just let it pump until it’s free of air, then tighten the bleeder back down.

I don’t use mityvacs. They don’t force the fluid out with enthusiasm like a typical pedal bleed can accomplish. Sometimes that is what’s necessary to get crud that settled in the caliper out. A mityvac will get the fluid out, but may not be the best tool for really flushing the system out.

 

Big thing is, if you're just flushing the lines, there's no issue, just perform a "bleed".

But there's no air in the system as long as its done right. Pump up, open bleeder, close bleeder, let go of pedal.

But if you run it low, or induce air, you'll need a techstream.

 

Thanks... Don't you start at the furthest and work your way in though- passenger rear, driver rear, passenger, then, driver? And if solo just gravity bleed till fluid comes out clean?

 

I don’t think order matters so much. I only follow that if the FSM tells you to - Toyota does not. I would do both on one end together, and then move to the other end.

You can gravity bleed but you’re going to be waiting quite a while. I would find a helper.

 

Order doesnt matter unless there's air.

I usually start at the fronts as they push the most fluid through quickest, then finish in rear.

 

If you have to replace the master cylinder on a newer Toyota it is a giant PITA to get the air out of the system. On my wife's Rav4 I had to use the scan tool to bleed the system twice and do a pressure bleed. It was the front brakes that were giving me so much grief, especially the passenger side.

 

Every single video I've seen highlights to start at the furthest and work your way to the driver. Is it because the system is different on the OR and pro models that the order doesn't matter?

 

I've done it twice on my truck, and a third time using the scan tool because I had to bleed the MC. All three times I started at the wheel farthest from the MC. I think that's the old school way I learned and I don't think there's a reason not to do it that way, although if bishop says it's okay to start at the front then I trust him for sure.

 

The idea is for air evacuation. Bleeding out air.

But for flushing there is no air so just push the fluid out.

If you want to be cautious use right rear, left rear, right front , left front, but my point is don’t stress about it.

 

I think the thinking behind following the age-old order is because if you have a system full of air, the quickest way to get it out is starting from the longest point so that you can pull fluid past the branch off points. For example, if you had one brake line on the left side of the frame that splits to go to left and right rear wheels, obviously the left is shorter. If you bled the left first, then the fluid would stop at the branch where it goes to the right wheel. When you go to the right wheel, you might introduce a bit of air back into the left as you pull fluid and air on by. If you started at the right side, you'd pull fluid all the way to the end, and then when you do the left you wouldn't disturb what went to the right because the left is the shorter run.

In reality, it shouldn't matter much. For a true air bleed, you should be doing all the wheels twice just to get any air that may have moved when switching between wheels. On a system with air I'll do 3-5 pumps per wheel and then go around again and do another 1-2.

For just fluid replacement like you're doing, like Bishop said, it doesn't matter. You're simply pushing fluid out, so the order you go in doesn't matter.