Brake system flush (1 Viewer)

Ok, I bought 6- 12 oz bottles of Toyota brake fluid and proceeded to flush the brake system, but ran into a few problems.

1. I was going to siphon/draw the fluid out of the reservoir with a syringe, but there are some bevels in there that prevent this. So, I thought I would just flush/bleed the lines.

2. Started with right rear, with assistant on brake pedal, cap on the reservoir, the ignition off. Got about 12 oz clear yellow fluid out- looked good. Checked the reservoir- still above the minimum line.

3. Went to left (driver's side) rear. Same thing, only about 4 oz's came out, fluid condition looked very good, then no more would flush. Repeated by closing valve, re-priming the brake pedal, opened valve. Again, only a small amount of fluid. At that point, I added 12 oz new fluid to reservoir.

4. Right front. pumped and held brake pedal, opened valve, a good squirt of brake fluid came out, clear as a whistle, then nothing. Closed the valve, repeated, and nothing. Turned key to acc (engine off) and tried it again, only getting a small amount of fluid out.

5. Same thing on driver's side front.

The good thing was the fluid appeared good as new. The bad thing was I thought I could run more fluid through it.

Anyone else tried this on a 100 series yet? Any tricks- I didn't know with the brake system the way Shotts described, if something else needed to be done. Also, what about a proportioning and bypass valve like on the 80's? The FSM mentions it, but doesn't say where it is or if it needs to be bled.

I suspect the motor needs to be running or the key/power on, otherwise it won't pump the fluid, isn't it a electic drivin pump or something like that? I know its not like a normal car(aka 97 and before cruiser)

So I say try it with the motor running

John

I would also guess that you'd have to have the engine idling so that electric pump in the master can work. From the previous posts regarding this master, there's a little reserve energy left, enough so the vehicle can come to a safe stop if the engine dies while driving. Just block the wheels to make sure the rig doesn't move when you're underneath and don't touch the exhaust.

Engine doesn't have to be running, just put the key to 'ON'. As you flush out fluid you'll hear the electric-hydraulic pump kick on. I was working on a '99 and got the right rear done with lots of fluid out, but then went to the driver's back tire and nothing would come out, then I realized the whole electric pump thingy, just put key to ON and it works fine.

Just got my '03 FSM's in the mail yesterday and was reading the section on brake bleeding. It seems to say to pump the brake pedal 20+ times, then crack open the bleeder valve (ignition "on"). It also has a bunch of stuff in there if you're using the Toyota ABS actuator tool or Toy/Lex hand tool. With the hand tool, it seems the easiest...select the wheel to bleed, crack the bleeder, then depress and hold the brake pedal. It wasn't clear in the FSM if conventional bleeding is accomplished by the pumping the brake 20+ times and cracking the bleeder, or if this method is to be used in conjunction w/ the Toy/Lex hand tool or Toy ABS actuator. Anyone know or have another interpretation?

It also says that if one pumps the brake pedal 40+ times w/ ignition "off", it'll go soft and throw will be longer, as the pressure in the master cylinder actuator has been relieved. Then turn ignition "on" and the pump should run for 30 sec or so and stop. If it doesn't, there's air in the master (this is what they say to bleed the master). It's all kind of confusing the way it's worded/organized.

Sometimes the translation in the FSMs leaves something to be desired.

Whether the problem happens Engineer -> Tech writer or Japanese -> English is a question I have thought about a couple of times while trying to do something with the FSM.

This front rotor thread also has great brake flushing info

Bleeding ABS systems (from Stoptech)

The Stoptech link is dead above. Here's the new link:

http://www.stoptech.com/technical-support/technical-white-papers/bleeding-abs-brake-systems

As an update to those unfamiliar with brake bleeding process on the hundy's the FSM can be a little confusing so going to try to break it down a little.

1. Use a handheld vacuum pump and remove as much of the fluid from the reservoir as you can. If you have a thin tube you can work it forward and get the fluid down to about half an inch left. Ideally you would get it all out first but unless your removing the whole assembly not really possible with this setup. Then fill back up to the max line and put the cap on. Be sure as you bleed each section your are keeping on eye on the level and adding as necessary.

2. If the fluid has gotten low enough that air is in the lines or you have replaced/rebuilt/etc the booster pump and accumulator the first thing you do is bleed that part of the system. This is accomplished by the first turning the vehicle off and pumping the brake pedal 40-50 times. You will feel it get very soft and can push it to the floor with little resistance. Then turn the vehicle on and time how long the booster pump runs. You're looking for a 30-40 second time frame. If it takes longer than that then do the cycle again.

3. If you have the hand held tester or abs actuator tool then use them to follow the flush procedure. But since most of us don't have one - get an assistant (buddy or one of your kids - my ten year old thinks she is pretty cool helping out). Turn key to on without the engine running, put assistant in the drivers seat, and have them press the brake pedal three times holding it down on the third time.

3. Starting with front left wheel, get brake bleeding line with clear tubing on the bleeder valve and into a container. You can do this without removing the wheel as long as your bleeder valves are reasonably torqued from prior work. With pedal held down crack open the bleeder valve. Fluid should run for 2-3 seconds then should stop. Close the bleeder valve and have assistant pump the pedal three more times holding down on the last and do it again. Repeat until no more air bubbles or fluid runs clear/clean. Follow same procedure for front right, then the rears. The ABS and brake lights may come on during this cycle - as long as you keep the fluid in the reservoir about the min line it will clear

4. Next is to force the abs valves to work. Again if you have the toyota tools they do it for you. But if you don't then you go find some dirt, get a little speed and romp on the brakes. Do this a couple times, then go bleed all four corners again then same way. This second time you shouldn't have to open the bleeder valves more than 2-3 times per wheel.

That's it - you have flushed the brake lines. If you have done this correctly and still have a soft/mushy pedal than time to either rebuild the master cylinder or get ready for the large hit on the wallet and order the new assembly.

Happy wheeling - Scott

Does the Tech stream software allow actuation of the abs unit?

I don't know if the Techstream software does or not, don't have access to it.

Best and easiest way to bleed the system is:

1. use Harbor Freight Pneumatic Break Bleeder ($30)
2. Vacuum pump (used Rigid 5 in 1 pump); kept at 90psi
3. Toyota Break Fluid

Last picture show old fluid. See the difference in color.

Engine was off. 1st removed old fluid, as stated before, can't remove all the fluid from the reservoir (see picture). picture). Fill the reservoir with new fluid. Now go and bleed all 4.

Good write up.
Warning: You'd better get it right or you might end up like me with an unplanned and expensive ($3200 just for parts!!) 2-day stop in a picturesque place like Maumee, Ohio while the local Toy dealer fixes things.
Ned

Onur aka beno once told me the SST for evac'ing the brake fluid within the ABS circuit was north of 3 large. Too bad we can't get 30 guys to coop it...and pass it around as needed. I just hate taking my LC in to the dealer...for anything! But keeping fresh fluid sans moisture out of the somewhat delicate ABS circuits little ball valves is very important to the health of the brake system...

The Toyota Hand Held Tester does run $3-$4k, the ABS Actuator Checker stand alone tool runs $300-$400 plus you need to buy the specific sub-harness for the vehicle - one of the websites I saw had one for the hundy for around $75. Either way spending $400+ for the tool doesn't make sense for me - if the shade tree version doesn't work the neighbor who works for the Toyota dealership can get me a decent discount on a quick brake bleed.

2003lx470 said:

Best and easiest way to bleed the system is:

1. use Harbor Freight Pneumatic Break Bleeder ($30)
2. Vacuum pump (used Rigid 5 in 1 pump); kept at 90psi
3. Toyota Break Fluid

Last picture show old fluid. See the difference in color.

Engine was off. 1st removed old fluid, as stated before, can't remove all the fluid from the reservoir (see picture). View attachment 1032383 View attachment 1032385 picture). Fill the reservoir with new fluid. Now go and bleed all 4. View attachment 1032374 View attachment 1032375

Click to expand...

That will only flush the primary channel. There will still be fluid and possibly air on the ABS side.

Slickspawn said:

Does the Tech stream software allow actuation of the abs unit?

Click to expand...

It has a test/flush mode but I couldn't get it to make anything shake or rattle when I tried.

Resurrecting an old thread since I couldn't find it.

How many ounces is needed to flush the brake fluid in a 100 series?

Couldn't find this easily and need to pick up some today.

SmoothLC said:

Resurrecting an old thread since I couldn't find it.

How many ounces is needed to flush the brake fluid in a 100 series?

Couldn't find this easily and need to pick up some today.

Click to expand...

Well, it's not a perfect science because you can't get all the old fluid out of the reservoir to start and you're eyeballing the color of the fluid flushed out. But I think I did a decent job of flushing, activating the ABS, and then flushing again with 5-12 oz containers of fluid.

Thanks @Sandroad - that's about what I thought.

That is similar to what I do. I get two bottles of the 32 oz Valvolene Synthetic DOT 3 & 4 fluid. I usually end up with a little left in the second bottle when done.