Replacing Parts in the Brake System

[AsH_]

i have problems with my EG in terms of brakes.

my proportional brake valve is leaking and i am going to rebuild my brake master cylinder...

i know i have to avoid getting air into the system, but i have to replace these parts.

so how should i take this on, as in the process?

do i drain the system of fluid to begin with?

once i install the parts, im going to have air inside, how i do i get them out?

any help will be appreciated.

[Paul1985]

You will need a syringe to suck all the brake fluid out of the master cylinder. When its time to reinstall it you will use new fluid and bleed the brakes removing all the air from the system.

Also remember that brake fluid is hygroscopic. That means it absorbs water, leaving the cap off the MC too long is a bad idea as it will absorb moisture from the air. Make sure your cap is sealing properly when you reinstall it all.

bleeding brakes isn't difficult.

GL

[AsH_]

thanks for your help.

i thought after i remove the fluid in the BMC, then i'll need to take off the proportional valve, but theres fluid in those hard lines?

its going to leak ?

[bennjamin]

it IS going to leak. Be ready for it with a takeaway container or two below to catch the fluid. Also use gloves and carry a rag with you to mop up excess fluid - keep it off your paint work.
OTherwise release pressure @ master cylinder and drain what you can , and then just take care undoing what you need , replace and retighten then rebleed the brakes :)

[shadou]

I used to bleed the M.C before placing it back on but that was due to time limitations placed. Dam you have a lot of problems with your car.
But yeah it's gonna get messy so a lot of rags and a guard cover if you have one or just some towels just in case some drips onto your fender.

[ECU-MAN]

regardless what you do your going to get air in the system.

thats why you bleed the brakes last.

[AsH_]

problems, its getting old i guess.

things are wearing out.

cars been pushed hard...

[riruiz_88]

hey dude, mine has started to leak as well. did you end up replacing the valve? is it simple to replace or do your really need to be mechanically minded? did you need to move anything while removing and installing the valve?

[shadou]

prop valve should be pretty easy, problem I see that you will find most challenging will be undoing the pipe nuts as they are usually very tight and very easy to round if not been careful, investing in a 10mm pipe spanner may save you a lot of frustration and it does come very handy when doing a m.c change over.

[riruiz_88]

yeh i am gonna get me a set, but thanks for the hit up. also when removing the valve, how are you supposed to get it out cause it seems that the brake lines will be in the way or do they just move out of the way easily?

[e240]

If my prop valve leaks, I'm going to change the system to a front rear and have a hydraulic handbrake!

Handbrake turns into the fishhook at wakefield FTW

[shadou]

yeh i am gonna get me a set, but thanks for the hit up. also when removing the valve, how are you supposed to get it out cause it seems that the brake lines will be in the way or do they just move out of the way easily?

uhh they should be d/c after loosening the nut, you can bend them but don't use excessive force as you can bend them very easily.

[riruiz_88]

dont understand what "d/c" is meant to mean, sorry. yes i have been told that you can remove with just moving the lines with not much effort. when re-fitting the fittings would i need to put any teflon tape on the thread to prevent any future leaks?

[bennjamin]

d/c = disconnected.

[riruiz_88]

what about my other questions???? please

[shadou]

..teflon tape lol no. After completing just tighten the brake line nuts to the prop valve as it came off and it should be all sweet along with a nice proper bleed to ensure any air is out.

[thepope1986]

when rebuilding master cylinder bleed it out on a bench. saves a lot of problems later when bleeding brakes. its pretty easy fill the reservoir up with brake fluid (you will need to put in a vice ((with soft jaws)) or hold against something solid but thats more difficult) block the holes where the lines bolt into then (you may need a friend) push the pushrod and slightly take your fingers off the holes. before the rod returns block the holes again as it will suck air in if you dont. do that repeatedly until you get brake fluid coming out smoothly. find some rubber bungs or something to block the line holes up with while installing the master cylinder to prevent getting air in. then bleed the system. also be careful with the proportioning valve as it adjusts the distribution of brakeforce between the front and rear of vehicle. good luck

[riruiz_88]

yeh i have heard that bench bleeding saves slot of time. how do you mean be careful with the prop valve? i know what it does.

[SPEEDCORE]

If my prop valve leaks, I'm going to change the system to a front rear and have a hydraulic handbrake!

Handbrake turns into the fishhook at wakefield FTW

While that may be so, not really an option for a road car. Well.. not legally anyway.

[thepope1986]

well i know with some vehicles mainly commercials and the like there are some adjustments on them which can adjust the way the brakes perform

[riruiz_88]

well you can different ratios for prop valves, but the honda ones arent adjustable as far as i know

[e240]

While that may be so, not really an option for a road car. Well.. not legally anyway.

The regulations specify that you need a dual braking circuits. it doesn't matter whether its front/back (some other cars) or diagonally (as in the Honda OEM design). So re-directing the circuit to Front back is not illegal.

You will also need a redundant braking system (which is fulfilled by the cable handbrake), just so long as you don't remove the cable handbrake system, you're still within the law.