Sr20fd3st

i feel like an *** asking this, but i went and flushed my brakes today using a pain in the *** mity vac pump. no matter how long i pumped the fluid would spurt out instead of come out in a continuous flow...after i filled half the catch can on each caliper i figured that was enough and that it was spurting out because the hose was bigger than the tiny hole in the bleeder. now when i get in and pump the pedal..it pumps up quickly and gets stiff and goes down right to where it should..only thing is after i let up for like 5 seconds all the pressure seems to be goena dn i have to pump them back up to get the pedal stiff. i'v always experienced the pedal to remain stiff..is this the result of air in teh system or is it leaking pressure somewhere? i didnt notice any puddles or anything..

chinoflyer

iTrader: (1)

I am not sure if I understand your post right. Are you using the vac pump to suck out the brake fluid at the caliper nipple? If you are I don't understand how it will spurt out? Nevertheless, if you are having problem bleeding it with vac pump, try it the old way, and have someone pump the brake while you bleed out each caliper. however air in the system does not feel that way. You can only tell air in the system when you notice not enough braking power when you are driving, when you are park, you pedal is going to get stiff regardless of air, well unless you are ALOT of air. Like if you forget to put fiuld back it when you change out your brake line, but I don't think that is your case.
as far as the pedal stiffness, are you feeling it with engine is running. most cars today come with power and abs brake. When your car is running if any part off the sub system fail your brake might just act weird. With the engine off, you brake should remain stiff after you pump it up, if not , you might consider getting a new master cyclidner (I know chinaman can't spell). I think you can get one at autozone for like 90 bucks. Sounds to me like your o-rings in your master is going out. well good luck, and let us know what you find.

rynberg

Do it the old fashioned way with two people..... read here for the proper method:

http://www.stoptech.com/tech_info/wp...edbrakes.shtml

Sr20fd3st

i know how to do it, i just didnt have anyone around at the time. neve rused the vac pump before adn never again my arms felt like popeye after i used the damn thing trying to maintaining 20 inhg of vac for that long... the motor wasnt running no. i just figured the pedal would stay stiff once i pumped it up but it only stays stiff for 5-10 seconds thats with a full master cylinder of course. i took all 4 calipers off the car to do some cleaning and ddint have pinchers to pinch the hoses so im sure alot of air got in the system which is why i flushed it with the mity vac and almost an entire big bottle of fluid. i just dont get the pedal feel

DaveW

There was a post a while back about soft brake pedal - it had to do with air possibly trapped in the ABS unit. There was quite a bit of discussion on bleeding, possible causes for low pedal, etc. Maybe this will add some insight.

https://www.rx7club.com/showthread.p...=brake+problem

Dave

Sr20fd3st

i'll check it out thanks

Sr20fd3st

after i read all that...all i had was some air in the front left caliper..alot of air lol. now the pedal is hard as a rock. i dont see why so many people had problems..i had all the same sysmptoms..peopel just dont knwo how to bleed their brakes. althought it was a little tougher on the fd than the other 1000 times iv done it...then again i didnt pinch off the hoses when i pulled the calipers so that mightv done it. o well problem solved

Mahjik

iTrader: (1)

This is why I recommend the Motive Power Bleeder (or any Power Bleeder, not a sucking type tool). Problems like that won't happen with the proper tool.

ccanepa50

iTrader: (1)

I used a mityvac for every event for years on my vintage car brakes and clutch, (non power steering) with no problems, however, it NEVER came out in a steady stream, with mine it was due to the hose not sealing and sucking air IN on the nipple, it was bleeding fine i just never got the satisfaction of that steady fluid stream......

Sr20fd3st

yea i didnt like that about the mity vac, hard to tell when air is done coming out..thats why i just let it fill up half the container everytime..too time consuming. i just did old fashioned brake bleeding and it's fine.

dgeesaman

iTrader: (7)

I too have not gotten good results from the Mityvac for bleeding. The problem I have is that the catch container in the kit doesn't seal worth a damn and that's kinda important.

There was however a time when I had changed my clutch line and the Mityvac was the only way I could get the bleeding process even to begin since there was no pedal pressure at all. But I never use it for bleeding brakes.

Dave

Sr20fd3st

haha believ eit or not i used that catch tank as an oil catch tank for the fd for a few months...i think the heat made the plastic all soft. that container never really could hold vacuum on it's own though..p.o.s...atleat the pump's still good for checking solenoids and all that crap.

btw has anyone ever retrofitted a hydroboost type power brakign system on their FD like hydratech's system? thsoe ***** have amazing stopping power..way better than a vac booster and im sure it could benefit people with significant ports and lower vac.

thirdtimesthecharm

Had to revive this one.

I bought a 7 dollar fluid/air pump for bicycle/car tires, hooked up the vacuum side to the nipples, and pumped away. This was after changing front calipers and flex line ends, so i had so much air in the system i needed a vacuum source to bleed.

7 dollar pump.

jkstill

iTrader: (11)

speedbleeders are the answer.

Bleeding brakes/clutch by yourself is pretty simple if
you just replace the bleed screws with speedbleeders.

Howard Coleman

iTrader: (6)

often the problem w mityvac is you suck air through the threads on the bleeder screws. i coat them w grease and all works fine.

howard coleman

dgeesaman

iTrader: (7)

Have you had any success using that Mityvac catch bottle? the air that thing leaks in is 10x that of any loose bleeder screw.

If using a better catch bottle would help I'd go back to using the mityvac for bleeding.

rx7will

iTrader: (6)

If you already have the vaccum bleeder and are tired of using the hand vaccum pump. Just discconect the hand pump and hook up engine vaccum to the catch can. You will need a really long vaccum hose to do the rear, or you could just use another car for the vaccum source. The catch bottle will fill up pretty quick. So you have to pay attention or the engine might suck up the brake fluid. But you need a really long vaccum hose.

Might sound kind of weird but it does work.

Sr20fd3st

lol, im sure it would work..but the piece of shti catch tank would still be leaky along with the hose not fitting right on the bleeder screw.

Actius

Not to bash on you or anything, but after reading your first post and then this....

Don't take it the wrong way, i'm just screwing around

DomFD3S

I've used the MityVac hand vacuum kit (the one w/ the reservoir to collect the old fluid) and have had no problems whatsoever.
http://www.mityvac.com/pages/products_hvpo.asp
Easily found at Harbor Freight.

Sr20fd3st

yea i feel like an ***