Bought an '05 4R for Danise and the kids (1 Viewer)

[marcfj60]

Hey Marc. Did you get your brake problem figured out?

I bought a used brake assembly from a 2010 4Runner for $300. I haven't had a chance to install it yet. I'm not sure if I can successfully bleed the brakes without Techstream yet. And if I replace the whole assembly, I probably need to calibrate the ABS and VSC using Techstream too.

 

[BionicCruiser]

see, 23k for and FJC w/ 85k miles and you'd have no problems for years.

 

[alia176]

see, 23k for and FJC w/ 85k miles and you'd have no problems for years.

That you couldn't wait to sell in short order

 

[marcfj60]

Installed the hydroboost motor/pump and accumulator last weekend. I bled the air out of the system yesterday. All is working well now. Because I opened the high pressure line to install the new/used parts, I was concerned about air in the accumulator and pump. I figure out how to power the pump straight from the battery, removed the end of the high pressure line where it attaches to the master cylinder, connected a clear tube to it and stuck the other end in a plastic bottle. Then I was able to pump about 2 cups of new fluid through the pump and accumulator and purge most of the air out of it before reinstalling the high pressure line and then turning on the key to pressurize the system. I then bled each corner until new brake fluid was coming out using the FSM procedure for brake bleeding. Everything is working well now. I took a bunch of photos but can't figure out how to get them off the phone and onto the computer. I'm sure Paige can show me how to do it.

 

[marcfj60]

 

[marcfj60]

Random photos of the 'new' motor/pump/accumulator. This supposedly came from a 2010 with 70K miles. It was in a lot better shape than the motor from my '05 with 200K on it.

 

[marcfj60]

Here is my rigged up manual pumping/bleeding setup to purge air and get new fluid into the pump and accumulator without getting a bunch of crap into the master cylinder.

 

[marcfj60]

These are the leads coming off the side of the ECU that power the pump motor. I just wired them straight to the battery to power the pump and purge the pump and accumulator.

 

[marcfj60]

And some random close up photos of what this thing looks like from different angles before I started disassembling the donor assembly.

 

[alia176]

Nice pics Marc. Can you post up some pics of the old motor innerds for a comparo?

 

[marcfj60]

I forgot to take some. Imagine the one you see here with about 10X as much carbon dust inside the housing and the brushes worn down about 1/2 way. I cleaned it all up before I reassembled everything and plan to keep it around as a backup. It still turned and the bearings sounded fine when I powered it from a battery so I figured it will work fine as a spare if the newer one ever wears out.

 

[alia176]

I forgot to take some. Imagine the one you see here with about 10X as much carbon dust inside the housing and the brushes worn down about 1/2 way. I cleaned it all up before I reassembled everything and plan to keep it around as a backup. It still turned and the bearings sounded fine when I powered it from a battery so I figured it will work fine as a spare if the newer one ever wears out.

So, the motor is fine but the actual master cylinder could be the culprit on the old unit?

 

[marcfj60]

So, the motor is fine but the actual master cylinder could be the culprit on the old unit?

I suspect either the pump or the accumulator. The motor still worked but it drives a pump (which I could not see any easy way to disassemble and inspect) and then the accumulator helps to create the pressure needed for the power brakes. I did not find anything obvious with my cursory removal and inspection. I did not replace the master cylinder, just the motor/pump/accumulator.

 

[Mauser]

Glad you got it figured out and it didn't cost too much. If you need it you are welcome to use my laptop with Techstream anytime.

 

[pappy]

Marc, this is one of those projects I would have to see to understand.

 

[onemanarmy]

Wonder why they decided to over complicate the braking system. Brakes have been working with vacuum/power steering assisted pumps for decades. Dead reliable and simple. Cheap too. Does that motor have an electric power steering setup? That's about the only reason there should be a separate motor and pump.

Drives me nuts.

 

[marcfj60]

Marc, this is one of those projects I would have to see to understand.

I barely understand it and I was right in the middle of it.

 

[marcfj60]

Wonder why they decided to over complicate the braking system. Brakes have been working with vacuum/power steering assisted pumps for decades. Dead reliable and simple. Cheap too. Does that motor have an electric power steering setup? That's about the only reason there should be a separate motor and pump.

Drives me nuts.

Best guess I have is that you need to have some kind of pump to operate ABS/VSC/Traction Control systems. Older vehicles had the traditional brake booster and then a separate pump mounted on the fender to function the ABS/VSC/Trac stuff. Toyota decided 20 years ago that they wanted to have one pump to take care of all the braking-related functions.

 

[pappy]

Toyota decided 20 years ago that they wanted to have one pump to take care of all the braking-related functions.

Something tells me that my Venza is set up something like this.

 

[onemanarmy]

Is there a way to bypass all that and just have normal brakes? For those of us that drive older stuff and don't want to deal with all that.