brake fluid flush

[andyli]

hi, guys happy new year. just want to ask how to do the brake fluid flush. there seems to be some posts on the forum but they are different. do not want to spend 50 bucks at the moment.

[kniever]

still a bit early to say happy new year yet, but yeah i'd like to know too as i just changed my rotors and pads and wouldnt mind doing the fluid just to make the whole lot all new

[jas98]

still a bit early to say happy new year yet, but yeah i'd like to know too as i just changed my rotors and pads and wouldnt mind doing the fluid just to make the whole lot all new

haha depends if u live in QLD or VIC NSW etc as of daylight saveings lol

[Just_a_stocker]

Well I can tell you how to do a brake fluid change?
Not sure about a flush, maybe there is somthing you can put down it that cleans the lines or somthing or you just take it to a place like midas and they will blow the lines cean with pressure.

To change the brake fluid you need -

-a jack

-a large bottle of brake fluid

-a small spanner

-a 600ml coke bottle cut in half (or somthing like that)

-a peice of plastic tube (preferably clear) that will fit securely over the -brake bleed nipple found on your calipers.

-a tyre socket or spanner to remove wheels

-a container to hold old fluid (plastic bottle)
preferably an extra person to pump the brake while you attend to the bleed.

do the wheels in this order - rear left, rear right, front left, front right.

*jack car and put blocks underneath

*remove the rear left wheel

*get access to brake caliper

*remove the lid of your brake fluid resovoir under bonnet

*loosen the bleed nipple (make sure you use a good fitting spanner as these are brass and can be damaged easily)

*push your peice of clear hose (has to be airtight fit) over the end of the bleed nipple and pump the old fluid out by pumping the brake.

*after it has fully drained, discard the old fluid and fill yr coke bottle up about 1/3 with new fluid.

This next bit is the critical bit and has to be done properly or you will leave air bubbles in the line and is best done with 2 people--

*with your 1/3 filled bottle place the end of the plastic hose in the fluid so it is well submerged in the fluid.

*get somone to add some new fluid to the resovoir (this has to be topped up while as needed to keep the lines full.

*Now hold your spanner on the beed nipple just before the shutoff point so you can nip it closed when the time comes

*get somome to give the brake a few slow pumps

*you will see a lot of air bubbles escaping from the end of the tube in yr bottle and this is why you keep the end of the hose submerged, so not air can go back in the line.

*pump the brake slowy till you see NEW CLEAN fluid come out of the hose.

*watch till all the air is removed , while somone slowly pumps the brake
eventually you will see no air but just fluid moving in and out of the hose
keep topping up the resovoir (it should really only take a couple of pumps)

*when you are certain there is no air in the lines get somone to slowly push the brake down and tighten the bleed nipple while the fluid is moving out of the tube, just at the final point when the brake is fully depressed.
(This is why it is best to have the nipple just turned before the cutoff point so you can close it nice an quick without stuffing around )

*do the same for all wheels exceot you may hve to pump a few times to remove the old fluid first so keep 2 bottles handy.

heh.. this might help or else I have just written the single most usless post ever.

cheers

[andyli]

Well I can tell you how to do a brake fluid change?
Not sure about a flush, maybe there is somthing you can put down it that cleans the lines or somthing or you just take it to a place like midas and they will blow the lines cean with pressure.

To change the brake fluid you need -

-a jack

-a large bottle of brake fluid

-a small spanner

-a 600ml coke bottle cut in half (or somthing like that)

-a peice of plastic tube (preferably clear) that will fit securely over the -brake bleed nipple found on your calipers.

-a tyre socket or spanner to remove wheels

-a container to hold old fluid (plastic bottle)
preferably an extra person to pump the brake while you attend to the bleed.

do the wheels in this order - rear left, rear right, front left, front right.

*jack car and put blocks underneath

*remove the rear left wheel

*get access to brake caliper

*remove the lid of your brake fluid resovoir under bonnet

*loosen the bleed nipple (make sure you use a good fitting spanner as these are brass and can be damaged easily)

*push your peice of clear hose (has to be airtight fit) over the end of the bleed nipple and pump the old fluid out by pumping the brake.

*after it has fully drained, discard the old fluid and fill yr coke bottle up about 1/3 with new fluid.

This next bit is the critical bit and has to be done properly or you will leave air bubbles in the line and is best done with 2 people--

*with your 1/3 filled bottle place the end of the plastic hose in the fluid so it is well submerged in the fluid.

*get somone to add some new fluid to the resovoir (this has to be topped up while as needed to keep the lines full.

*Now hold your spanner on the beed nipple just before the shutoff point so you can nip it closed when the time comes

*get somome to give the brake a few slow pumps

*you will see a lot of air bubbles escaping from the end of the tube in yr bottle and this is why you keep the end of the hose submerged, so not air can go back in the line.

*pump the brake slowy till you see NEW CLEAN fluid come out of the hose.

*watch till all the air is removed , while somone slowly pumps the brake
eventually you will see no air but just fluid moving in and out of the hose
keep topping up the resovoir (it should really only take a couple of pumps)

*when you are certain there is no air in the lines get somone to slowly push the brake down and tighten the bleed nipple while the fluid is moving out of the tube, just at the final point when the brake is fully depressed.
(This is why it is best to have the nipple just turned before the cutoff point so you can close it nice an quick without stuffing around )

*do the same for all wheels exceot you may hve to pump a few times to remove the old fluid first so keep 2 bottles handy.

heh.. this might help or else I have just written the single most usless post ever.

cheers

thanks heaps mate. complicated, but I might try later.

[Not_An_Abba_Fan]

I would suggest a slight change to the bleeding procedure.

Instead of pumpimg the pedal with the bleeder open, you should open the bleeder then push the pedal down half way, close the bleeder, release the pedal. Do this until you have a clean steady flow of fluid with no bubbles.

Reason: Pushing the pedal all the way to the floor will push the seals in the master cylinder past their normal travel and may damage them. Over time the piston will wear the bore in the m/cyl and at the end of it's stroke there will be a slight shoulder, if you push the seals past this point the shoulder cuts into the seal and then you will have a by passing master cylinder. This will not happen every time, but avoiding the possibility is always best.

Using the open, push, close, release method will prevent sucking back of the fluid when you pump the pedal with the bleeder open. If the end of the bleed tube is submerged in brake fluid, you will not suck back any air, but it does take longer because you are pushing out the fluid that was sucked back first before new fluid is pushed out.

Another thing, instead of pumping the fluid out first and filling the whole system with air, use something to suck the old fluid out of the reservoir first, then wipe it out with a clean rag, then refill with new fluid and start bleeding. This will prevent air entering the system and makes the bleeding procedure faster. If you have ABS, do not allow air to enter the system because you will need a Tech 2 to be plugged in to cycle the ABS unit to remove all the air in it.

(Just read that you have a VN, probably no ABS so disregard that last comment.)

[andyli]

I would suggest a slight change to the bleeding procedure.

Instead of pumpimg the pedal with the bleeder open, you should open the bleeder then push the pedal down half way, close the bleeder, release the pedal. Do this until you have a clean steady flow of fluid with no bubbles.

Reason: Pushing the pedal all the way to the floor will push the seals in the master cylinder past their normal travel and may damage them. Over time the piston will wear the bore in the m/cyl and at the end of it's stroke there will be a slight shoulder, if you push the seals past this point the shoulder cuts into the seal and then you will have a by passing master cylinder. This will not happen every time, but avoiding the possibility is always best.

Using the open, push, close, release method will prevent sucking back of the fluid when you pump the pedal with the bleeder open. If the end of the bleed tube is submerged in brake fluid, you will not suck back any air, but it does take longer because you are pushing out the fluid that was sucked back first before new fluid is pushed out.

Another thing, instead of pumping the fluid out first and filling the whole system with air, use something to suck the old fluid out of the reservoir first, then wipe it out with a clean rag, then refill with new fluid and start bleeding. This will prevent air entering the system and makes the bleeding procedure faster. If you have ABS, do not allow air to enter the system because you will need a Tech 2 to be plugged in to cycle the ABS unit to remove all the air in it.

(Just read that you have a VN, probably no ABS so disregard that last comment.)

how much fluid should I buy and how long will it take? should I buy sythnthetic or mineral?

[Not_An_Abba_Fan]

Any DOT4 brake fluid will be fine. I wouldn't go synthetic as the extra money you pay won't give you any more performance in a street car. You should only need a 500ml bottle.

[PREDATR]

This is a very important comment, if you dont do this then as said the seals will get damaged and you won't be able to bleed the brakes up they will just feel spongy and you'll be up for a new master cyl.

I would suggest a slight change to the bleeding procedure.

Instead of pumpimg the pedal with the bleeder open, you should open the bleeder then push the pedal down half way, close the bleeder, release the pedal. Do this until you have a clean steady flow of fluid with no bubbles.

Reason: Pushing the pedal all the way to the floor will push the seals in the master cylinder past their normal travel and may damage them. Over time the piston will wear the bore in the m/cyl and at the end of it's stroke there will be a slight shoulder, if you push the seals past this point the shoulder cuts into the seal and then you will have a by passing master cylinder. This will not happen every time, but avoiding the possibility is always best.

Using the open, push, close, release method will prevent sucking back of the fluid when you pump the pedal with the bleeder open. If the end of the bleed tube is submerged in brake fluid, you will not suck back any air, but it does take longer because you are pushing out the fluid that was sucked back first before new fluid is pushed out.

Another thing, instead of pumping the fluid out first and filling the whole system with air, use something to suck the old fluid out of the reservoir first, then wipe it out with a clean rag, then refill with new fluid and start bleeding. This will prevent air entering the system and makes the bleeding procedure faster. If you have ABS, do not allow air to enter the system because you will need a Tech 2 to be plugged in to cycle the ABS unit to remove all the air in it.

(Just read that you have a VN, probably no ABS so disregard that last comment.)

[Just_a_stocker]

Yeah sorry about that

I have bled mine quite a few times with no such probs,
also I originally used the Gregories manual to get this method and there is no mention of a warning in it about the brake depression thing (just checked it).
Actually it says to depress it but I guess it means not all the way to the floor but doesn't actualy clarify that point.

Good point though.

cheers

[Not_An_Abba_Fan]

A lot of times a manual will give instructions on bleeding brakes with all new components. If it was a new M/cyl, it wouldn't matter.

[peter65]

andyli - it is a lot easier than it sounds. i have been putting this job off for over 12 months and i did it alone on the weekend.

It is a bit of a pain doing it on your own. The actual bleeding is easy & all up only took me about an hour. The worst bit of the job is getting all of the wheels off one by one - the actual brake bleeding is easy!

Oh and a word of warning - keep the brake fluid right away from the paintwork. it will damage it in no time (a good idea is to read the directions on the fluid container about how to clean up a spill before doing the job so that if it happens you can clean it up straight away).

The problem with mine is the old fluid was really murky i guess because it was so old... so i will need to do it again in a month or so so well and truly flush it all out (and when the memory of all the jacking up/wheel off/wheel back on has faded somewhat).

Cheers Pete

[andyli]

andyli - it is a lot easier than it sounds. i have been putting this job off for over 12 months and i did it alone on the weekend.

It is a bit of a pain doing it on your own. The actual bleeding is easy & all up only took me about an hour. The worst bit of the job is getting all of the wheels off one by one - the actual brake bleeding is easy!

Oh and a word of warning - keep the brake fluid right away from the paintwork. it will damage it in no time (a good idea is to read the directions on the fluid container about how to clean up a spill before doing the job so that if it happens you can clean it up straight away).

The problem with mine is the old fluid was really murky i guess because it was so old... so i will need to do it again in a month or so so well and truly flush it all out (and when the memory of all the jacking up/wheel off/wheel back on has faded somewhat).

Cheers Pete

many thanks Pete, I will try it after next week. my brake feel spongy, that is after Bendix ultimate front and rear.