: Spongy Brakes


Commutacoma
10-11-2005, 09:39 PM
:confused: To make a long story short, I bled my brakes again tonight.

The order I used was:
RR
LR
RF
LF
then
LPSV.

I had someone pump about 5 times and while holding the pedal down, I opened and closed the nipple thing. I repeated about 6 times per wheel and lpsv. The braking seems better now, but still somewhat spongy.

At 2-3 miles/hour, if I jam on the brakes, I would think the truck should come to an immediate halt. It does not.

This is about the 3rd time in a year that I have felt the need to do this.

Any thoughts on this?

_BEN_
10-11-2005, 10:13 PM
You could have brake line contamination. (water) That can cause irratic brake feel.

If you do not like the initial bite of the brakes go and get some performance brake pads. Axxis ultimates and Hawk HPS have pretty good initial bite.

AK98Taco
10-11-2005, 11:04 PM
-Poor performance from booster, i.e. vacuum leak
-One or more of the seals in the master cylinder is faulty
-Leak
-Rotor is too thin
-Caliper is frozen or a seal on one or more of the pistons is faulty

tacotoy
10-16-2005, 12:27 AM
mmmmm im going to have to roll with aqua in the brake lines too. when was the last time that you had your brakes done or just the fluid changed in general. with all of our nifty weather n stuff here its almost a fact of life. has this only been happening as it has been getting colder or ongoing? if its ongoing i might also look into the master cylinder and make sure that your seals on that aren't going out either. yada yada....... i hate brakes lol

Guapotaco
10-25-2005, 02:59 PM
i've done mine a few times and it never has a stiff pedal fell afterward,anybody know if these systems need to be pressure bleed? i did mine similar once, but my friend says to only pump once and then lock it off and chk fluid and then go again,1 pump at a time? he's done this for about 30 years on an american setup with no problems,your not letting your fluid get to low when your pumping are you? if it gets too low it'll suck air in and then it's back to the top again,dumb ? but...you never know

Commutacoma
10-25-2005, 08:09 PM
After I did my pads and calipers in Nov 2003, I was unhappy with the pedal feel and during that time I moved to a hotel as I was between homes. Lacking a work area, I went to brakes plus and paid them to do a fluid change where they pushed more fluid through while they had some contraption on the master cylinder keeping the system under pressue. It seemed to be a good job.

After my last bleed when I posted this thread, the brake pedal has seemed better. I am not afraid of ramming someone on Broadway at 5:10 PM downtown. High speed braking to me at least seems better than low speed.

tacotoy
10-25-2005, 09:10 PM
ummmmm if i remember right brakes should go pass rear driver rear then the BPV valve( lool up above your axle. yes it is a seperate bleed point.) then pass front driver front to bleed down the system. should be a 1 pump deal or pretty much when fluid comes out. i would have to say its a 2 person job though as you should be closing the bleeder with brake fluid coming out. if you are doing it by yourself when you let off the pedal and the master cylinder relaxes it could be sucking air back in thru that open bleeder instead of pulling fluid from the low side of the system

_BEN_
10-25-2005, 09:13 PM
I've done mine a few times and it never has a stiff pedal feel afterward, anybody know if these systems need to be pressure bleed?

Pretty much how I bleed my brakes is...

1. I set a bottle of brake fluid on top of the MC like a arrowhead bottle sits on its water cooler.
~This way the MC will always have a constant supply of fluid. Sounds crazy but it works really good. Make sure you wipe up all spills asap because brake fluid eats paint.

2. Then for a flush I will open the bleeder (one wheel at a time) and have my helper pump untill I see clear fluid at each wheel.
~Always checking my bottle still has fluid. A piece of $.99 black vacuum tubing helps direct the flow from a bleeder into a jar.

3. Then I have my helper pump the brakes until the pedal feels firm. While they hold the pedal down I will open and close the bleeder quickly. Long enough to let some air/fluid out but not long enough to let the pedal bottom out.
Repeat as many times as needed untill no bubbles squirt out.
~Keep the end of the vacuum tube submerged in the jar. This way you will be able to tell whether or not air is still in the system(you will be able to see the bubbles floating to the surface of the fluid). This also helps keep air from getting sucked back into the system as well.

Start with the back drums then work your way to the front right and end with the front left.

Another thing that affects pedal travel (something that can be translated into a "spongy" feeling)is the adjustment of the rear drums.

BTW: This is just how I was taught and it works for me. If you were to ask how to bleed your brakes I am sure you will get similar answers with many variables.
:kewl:

blown4runner
10-28-2005, 04:44 PM
Um, may sound stupid... but how is the adjustment of your rear brake shoes? And is your LSPV adjusted correctly???

Commutacoma
10-28-2005, 09:21 PM
I have not checked the rear drum adjustment. I use the parking brake all the time, but I do not think it is tightening the rears at all.

I have bled the LSPV, but have not adjusted it. I did not know it required adjustment. Everything I have read has said the LSPV needs to be bled last which is the way I did it.

Maybe I will crawl under the truck and try to tighten the drums

blown4runner
10-29-2005, 12:04 PM
Just figured I'd put something out there, figured you guys had probably laready attempted this. Tacoma don't have self-adjusting parking brakes. They need to be manually adjusted through a opening in the backing plate of the drums. If they haven't been adjusted in a long time that would be the first place I would look. The best way to adjust is to raise the rear end of veh, remove both tires and adjust the star wheel till there is slight drag. There's no real accurate way to do this with the veh on the ground.

As far as the LSPV, I seriously doubt even if it isn't adjusted correctly it would cause a spongy pedal. Although they do need adjustment... especially if your taco is lifted. There are special relocation brackets to raise your LSPV to account for the difference created bewteen the rear drums and the frame of the truck when you lift it. All the LSPV does is take into account load in the bed of truck and apply brake pressure to the front or rear accordingly. When a veh is lifted all the LSPV sees is there is no weight on the rear of the veh. By even adjusting this the way your veh brakes will improve. ALthough the only way I know how to adjust this is a little complicated and involves scales and such. But this issue could be a lot of things. I am just all about keeping it simple stupid before getting complicated. Hope this helps a little :o