so, when my car is off, and someone is pumping the brake pedal (whether bleeding the brakes, or just pushing the pedal) once the pressure gets pretty high, it makes a faint sound like a retarded llama. i JUST put new rotors and pads on last night, and bled them this morning. pedal pressure feels pretty decent for rubber lines.. but i still had a tiny bit of freeplay. so i adjusted the pedal, stepped on the pedal lightly 4 or 5 times (no freeplay) then pushed hard on the pedal and the same amount of freeplay returned (about 1/4" or so. i never actually measured it). So... does the llama sound plus incurable freeplay point to a bad master cylinder?

now that my repertoire of automotive skills is ever-increasing...
IF it turns out my master cylinder does in fact need replacement, I have a spare master cylinder I guess I could rebuild, rather than replacing w/ a new one... or is it best to replace anyway?

 

So your brakes sound like this?
http://www.youtube.com/watch?v=B_PAQ...eature=related

 

LOL no it's kinda like... chewbacca. perhaps i can set my camera down on the brake fluid reservoir lid and capture the sound.

edit: nevermind... batteries died. don't have any fresh batteries handy.

 

lol A llama sound?

like this?

http://www.youtube.com/watch?v=HCPZY...eature=related

 

Hm then like this?
http://www.youtube.com/watch?v=VsNk6iKk_Io
But anyway a sound clip would help.

 

dude.....

 

actually.... it kinda is a little like that, just only does it for about a second, and fades in/out smoothly (volume-wise)

anyways.... would that be the sound of the brake fluid slipping past the seals of the master cylinder? the sound eminates from the master cylinder but i've never heard a NEW master cylinder... so i wasn't sure if the sound was normal or not.

 

At least we know what it sounds like.

 

it's fairly faint. if the radio is on at normal volume, you won't really hear it. but you can hear it through the firewall when the engine/radio are off.

 

Actually, both my maxis have made that sound before, i believe it is the diaphragm in the booster making the noise. I just ignored it and went on.

 

hmm

then, thoughts about the freeplay? when the car is off it goes about 1/4" until it hits ANY resistance at all (other than the return spring). i adjusted all the freeplay away, pressed lightly (it was fine), pushed HARD and the freeplay came back. the pedal adjuster is now just about bottomed out.

Front brakes are new (pads and rotors). cleaned and greased liberally. piston was FULLY retracted in order to fit the calipers onto the brakes. rear brakes were done in august with new rotors, and plenty of pad material still... also greased liberally. rubber brake lines. any thoughts?

 

I think it's just from no vacuum pressure in the booster, i don't think anything is broken.

 

hm ok... yours does that too when it's off (the freeplay amount)? i'll let you know how these brakes feel as they get broken in better... should be nice. more on that tonight..

 

It's not broken unless you have minimal brake pressure....Great thread title...

 

You need to stop "adjusting" things..

 

Never heard how llamas faint, uh. None around.

Whatever, theyre noisy if alive. Only dead ones are silent. Brake em or not.

 

well the brakes aren't GREAT yet... but then again i only have like 30 miles on them and 25 of that was 65mph on the highway. smooth, just working on getting them to grip. still have the crosshatches on the rotors. but pressure seems OK. probably rebleeding it later on.

i, er "adjusted" the outside diameter of my rotors now 11.65"

but actually, my car is SOOOO much better than it was this time last week. mounts.. brakes.. swaybar (placebo maybe?).. fixed exhaust hanger.

 

Sounds like the Booster is about to go, possibly from the M/c leaking brake fluid into the booster. Or the seals in the m/c grabbing the cylinder walls and making that sound.

 

well i've noticed that now matter how much I bleed it... the pedal is never QUITE as firm as i'd like. I LOVE the pedal feel of my mom's car, a 99 2.2L camry. i almost always stop short in her car, but i never feels uncomfortable. Actually, on hers, as you get down to 20mph or so and it starts kicking back through the gears at idle, it sucks the pedal down just a tiny bit more than it did for the front half of the stop.. it's incredibly secure-feeling and comfortable. And she's got drums in the back...

I have a spare booster on the parts car.. I guess I could try that. minus whale bench bleed the mcyl as well, and rebleed the rest of the car after that. i ought to get some of that blue brake fluid.. the kind for verifying you flushed it completely.

 

I guess maxima was born with softness; at least my max has always been like that... I guess its ABS related (I could bypass ABS and check that)?

 

i think its ur booster....cuz wen the car is off and u pumping the brake pedal it should hold some vacuum as theres always lil bit of vaccum left in the booster even if the engine is off...and its not holding that vaccum and u have freeplay in pedal and for Llama noise LOL i think it could be the output rod in the booster?

it has ntn to do with bleeding brakes if u have done it already...

 

I don't have ABS tho. no automatic hydraulics on this car anymore haha. not since.. uh, feb 18th 2008 when the auto tranny died.

i suppose.. it doesn't seem to be any sort of critically imminent failure, so unless something actually comes of it, i won't make it a big priority. i have a spare booster that i'll put on whenever i get a round tuit.

 

so did u put new booster on? or it was something....?

 

no i haven't messed with it yet. being that i don't have a job i'm not taking any risks tearing apart parts of my car that are passable for the time being. once i have cash to fix anything i break, i'll look into it more deeply.

i actually haven't driven my car since sunday night...