bishop977

i'm planing on bleeding my brakes this weekend. just want to make sure i got the proper procedure down.

Car needs to be on
remove dust cap on bleeder valve.
attach a hose to the bleeder valve to catch all the fluids.
press on the brakes and open the bleeder valve, have the person hold it while its down and close the valve. let the pedal go back up and open the valve and press the pedal down again. hold the pedal in down position and close the valve and let the pedal back up. until all the air is out.

question
do i have to have the car on to bleed it.?
do i have to start from closest to furthest.?
does the hose to catch the fluid have to be flush so no air will go in?

i tired this last week. and the bleeder hose i got at pep boys didn't fit too flush on the bleeder valve and when i pumped the brake pad, fluids came out but the hose didn't collect all the fulids some leaked out. i was kinda worried that air might leaked in. i dink i did it wrong i tried bleeding with the car off. and took me and my friend 4 hours to do it. it worked but it was still mushy a little more mushy than usally. figure it wasn't the proper way of bleeding it. i looked it up. and i found that the car should be on.

/Aerostar\

iTrader: (2)

no no, the car should be off. And another thing, I dont really understand your description of how you did it. You should:
- Siphon out all fluid from resoivoir and fill with new fluid
- Press brake pedal down and hold it, while someone is opening the valve and letting the fluid out.
- Close bleeder valve, and let the pedal up
- Fill resivoir with new fluid.
- Repeat #2 - 4

btw, I hate the word 'resovoir'

SeattleGS400

iTrader: (1)

Was looking at the factory bleed for my '99 GS400, and they mention that you should bleed in this order:

R front (passenger's) side
L front (driver's side)

R rear (passenger's) side
L rear (driver's) side

TxLexus

I havent looked at any the factory manual. Correct me if I am wrong. But this is the order you need to follow

Farthest first

Rear passenger side
Rear Driver side
Front passenger side
Front driver side.

Dont need to have the motor running. You can if you want. Doesnt make a differences.
Always make sure the resevoir is filled. leave the cap off.
Have your buddy pump the brake pedal 2 times 3rd time hold it. you release the bleed valve at the caliper,the fluid squirt, then tighten it. then your done. Go to the next one.

Good luck.

Carpe Diem

I think all this "bleeding order" stuff is BS. Someone please explain to me why it matters.

Thanks,
George

bishop977

really i thought the car had to be on i heard to bleed it. cuz then the pump won't work..i read your not supposed to pump the brakes thats how air gets in..

Cadd

This is confusing. I will be bleeding mine pretty soon. I'll be watching this thread closely for the "correct" way of bleeding.

Fern

Bleeding is done one wheel at a time. The "old timers" will tell you to start with the wheel furthest away from the master cylinder and then work your way closer. Typically, this would mean RR, LR, RF, then LF. However, it doesn't really matter if you start with the front or rear wheels, since they are on separate brake circuits on modern cars with ABS and/or dynamic stability control systems. However, you should start with the passenger side wheel and then do the driver's side.

You'll need 1/2 - 1 litre of fluid. If your a novice or are installing a big brake kit (which means you should know how to bleed brakes), maybe more.

1.Block a front wheel with a piece of wood to prevent the car from rolling. Raise the back of the car with a floor jack and then lower it onto a pair of jackstands.

2.Remove the rear wheels.

3.Open the hood and remove as much old brake fluid from the reservoir as possible, using a suction tool or a turkey baster. Be careful not to spill any fluid, as it will dissolve the paint on your car.

4.Fill the brake reservoir to the top with fresh fluid.

5.Place a box end wrench over the bleed screw on the right rear caliper. Push a clear plastic tube over the nipple on the bleed screw and place the opposite end into a bottle. Alternatively, you can buy a catch bottle with a cover that prevents fluid from spilling if it tips over, a 1-way check valve in the cap, and a rubber fitting on the caliper end of the plastic line that snaps in place over a wide range of bleed screw nipple sizes.

6.Tell your assistant to pump the brake pedal a few times until it becomes firm. This is especially important if you have just replaced pads. If you've installed new stainless braided brake lines or installed a big brake kit, there may be enough air in the system that the brake pedal will not get firm. That's OK. Just move on to the next step.

7.Tap the caliper a few times with a rubber mallet. This helps to release air bubbles that may be clinging to inside surfaces of the caliper.

8.Have your assistant PUSH hard on the brake pedal and HOLD. Then quickly, crack open the bleed screw about 1/4 turn. Fluid (and probably a few air bubbles) will flow through the plastic tube and into the catch bottle. A light placed behind the tube will make it easier to see what is coming out of the caliper.

9.Close the bleed screw just before the brake pedal reaches the floor. Don't worry if the timing is off at first. You will quickly figure it out with feedback from your assistant.

10.Tell your assistant to RELEASE.

11.After a brief moment, repeat steps 8 - 10. Do this about 6 times and then go to the front of the car to make sure the fluid level has not dropped too far. You MUST not allow the fluid level to fall to the point where you are sucking air through the master cylinder.

12.Top off the brake fluid level and continue for a total of about 10 pumps or until you no longer see any air bubbles coming out of the caliper.

13.Repeat the process for the other rear caliper.

14.Make sure both calipers are wiped clean of brake fluid and that none has spilled on the rotors or pads. Use brake cleaning spray if necessary. Reinstall the rear wheels and torque to factory specification, then lower car to the ground.

15.Now apply the parking brake, put the car in gear (or PARK) and raise the front of the car with your floor jack. Lower it onto a pair of jackstands.

16.Remove the front wheels.

17.Follow the exact same technique as with the rear wheels, starting with the passenger side caliper. The fluid will flow more rapidly out of the front calipers, so you will need to check the level in the brake fluid reservoir more frequently to avoid letting it drop too low.

18.Reinstall and torque the front wheels, then lower the car to the ground.

19.Top off the brake fluid reservoir and replace the cap.


Or alternatively, take it to a competent mechanic and pay $70-$100 to have it done.

Cheers,

Fern

SeattleGS400

iTrader: (1)

Fern:

Awesome info The factory manual only has steps to do it using their Lexus diagnostic machines to control the brake pumping electronically (via the ABS actuators). Anyways, I appreciate your detailed brake bleeding procedure as it makes things much clearer--you just saved me $90. I'll get it done in a few months!

XYZLexus1

Great Write-up. So am I correct in saying you do not need the diagnostic tool to blead the brakes and it is the same as bleeding the brakes on my 1976 Cadillac Eldo Convertible which came with the largest production motor ever produced 8.2 liters or 501 cubic inches.

bishop977

nice write up, but the does the car have to be on to do it? some said yes some said no....

/Aerostar\

iTrader: (2)

no it does not, and nice write-up Fern

Cadd

Nice writeup Fern! I'll be doing this as well. This maintenance section of the board is saving me lots of $$$ as well as teaching me mechanical things about cars that I would have never known about

csaxon

Just a NOTICE that's in the factory manual under step 3 CONNECT VINYL TUBE TO BRAKE CALIPER BLEEDER PLUG.
The NOTICE say "Bleed air off the rear brake first. If front brake is bled first, all rear brake air cannot be bled. The bleeder plug tightening torque is 74 in-lbs.