brake fluid reservoir

[redSRpilot]

i noticed the other day that my manifold had melted a hole in my brake fluid reservoir. so i picked up a new one at the junk yard and threw it on. then i started bleeding the brakes and they weren't getting any stiffer and peddle just keeps going to the floor. so i kept doing it and doing it and still not any better. there are no leaks in lines or calipers anywhere but there is a little brake fluid around the grommets between the reservoir and master cylinder. could this leak keep my brakes from working? im not sure if the reservoir needs to be completely sealed for the brakes to work? and if this leak doesn't matter then im guessing my master cylinder is bad.

[PEZi]

anything before the master cyl should not cause this, it would have to be the master cyl or something after it. i assume you made sure all the bleeder screws were tight, right?

[DanThaMan]

bleed the master cylinder?

[OutToWinPAHC]

Bleed in proper order, rear driver, rear passanger, front passanger then front driver. Repeat as needed.

[redSRpilot]

yeah i made sure all bleeder screws were tight and i also bled in the proper order. i think i might just replace the master cylinder tomorrow.

[redSRpilot]

i just thought of this but wouldn't a leak at the grommets (being at the bottom of the reservoir) be the same as running low on fluid and sucking in air while your bleeding?

[allenms240]

Ia it just a new reservoir? Might want to try bench bleeding the MC with the reservoir on it.

[scooz14]

odds are if you melted the res, you also fried the seals inside the bmc

[redSRpilot]

so i went to the junk yard yesterday and got a master cylinder off a 300zx. the thing looks brand new, so i threw it on my 240. once again bled the crap out of it, and still no brakes. it bleeds good, im getting a solid stream of brake fluid and no air. still no signs of leaks anywhere. i havent bench bled the mc yet, but ive never had to do that before to get it to work, plus im not getting any air so i think they are bled good. im getting new rubber grommets tomorrow for in between the reservoir and mc, but im not very confident thats going to fix it. any other suggestions??

[OutToWinPAHC]

Can you please tell me how you bleed your brakes? I just want to make sure your doing it correctly.

[redSRpilot]

ive tried a few different ways. i did it in the right sequence first off. rear passenger, rear driver, front passenger, front driver. i had a friend push down on the peddle, then i opened up the bleeder screw until the fluid stops coming out, close the bleeder screw, then release peddle. repeated multiple times. sometimes i would have my friend pump the brakes a few times then hold before i opened the screw and so forth. i always made sure to keep the reservoir full. i tried with the reservoir cap on and off but it didnt make any difference. i was getting a solid stream of fluid out of all four too.

[OutToWinPAHC]

sometimes i would have my friend pump the brakes a few times

All looks good except this, this can actually move the bubbles around. Repear, but no multi pumps. Down, open, close release repeat.

[redSRpilot]

did that too but didnt work. so i tried pumping it before opening it. i feel like i just got unlucky and got another bad master cylinder...

[Didderson]

you're using junkyard parts... The seals go bad on them and when you change the fluid it flushes out the gunk that was keeping the seals working.. So you should just get a new master cylinder. Iv had this happen when bleeding a friends brakes. Just kills the old master w/ new fluid.

[redSRpilot]

I didn't mention that I took off the calipers because I didn't think it was relavent to my brakes not working, but I read online that if the calipers are put back on the wrong side (with the bleeder below the brake line) that they will still bleed good but there will be air trapted in the caliper that won't come out. The bleeder needs to be on top that way the air can rise and escape. I always thought calipers could be used on either side. Has anyone heard of this?

[redSRpilot]

flipped the front calipers around so the bleed screw was above the brake line, bled each caliper a couple times, and they work like a champ now.

[OutToWinPAHC]

Oh that was a basic mistake, good find