S

synchro

Well-Known Member
Heyo

My brake fluid is abit nasty.. and my pedal is behaving abit spongy.
I believe i really need a change.

However, when taking a look into the workshop manual, i can't figure out the capacity for the brake system.

I think i should flush the system, as the fluid is quite nasty.
Atleast try to change it all bit by bit....

I also see in the manual "Do not use mineral oil"

I was thinking of using the Bosch DOT 4, universal brake fluid. (Which is mineral oil)....

What i find odd, is that previous owner swapped the brake accumulator or whatever its called for less than a year ago, i assume he must've used new brake fluid, but damn its nasty??

Its quite goeey, and miscoloured, a mixish of yellow/grey/black

Brakes work... Just pedal being bit spongy.

If i were to change the fluid what kinda equipment would i need? I heard one dont need to press the brake in the p38 to bleed the system, just ignition on and the pump does the job?
 
Changing the accumulator does not involve a fluid change. Ideally the fluid needs to be changed every 2 years.
You need to follow the instructions in RAVE exactly for bleeding the system. Use the fluid specified in RAVE. Some one to press the pedal when needed helps and an ezibleed kit I just bought 2 litres of fluid to ensure I could do a good flush and not run out.
 
VS820.V4_DFC15460.png
even easier on your own... Not cheap but very effective;)
 
Mark Piercy said:
View attachment 250168 even easier on your own... Not cheap but very effective;)
Click to expand...

what is that? It looks like it screws onto the reservoar? Is it to keep the brake fluid topped up while bleeding and not letting air in or is it to drain? never seen one of thoose before.

ive only seen thoose who you attach to the bleed valves, often with a oneway valve, i heard oneway valves are a must if bleed by myself? Otherwise it just get sucked back? :)
Thanks for helping me btw guys, its so kind :)
5star service on landyzone as always :cool:

My P38 appriciates it :D
It has not been the most well maintained car, but i’ve done lots, lots to it. As deserved.

might treat the beast with AT KO2, it dosnt mess with air suspension does it? (Rave said only OEM tires/dimensions (i have 245/70/16))

and is the KO2 good in wintertime? (I might have throwaway winter tires, might…)

and i obviously want to drive some offroad cuz thats fun af :D
 
It does screw into the fluid reservoir, you fill it with 1or 2 ltrs of brake fluid, it's then pressurized by pimping the handle up and down. You then go around the bleed nipples in order on the P38 brake system and the tool pushes the fluid through with no air and under pressure. I have it in the garage and it's been used on many vehicles with and without abs and never fails to do a good job. Not cheap but does give a really good result. :cool:
 
synchro said:
what is that? It looks like it screws onto the reservoar? Is it to keep the brake fluid topped up while bleeding and not letting air in or is it to drain? never seen one of thoose before.

ive only seen thoose who you attach to the bleed valves, often with a oneway valve, i heard oneway valves are a must if bleed by myself? Otherwise it just get sucked back? :)
Thanks for helping me btw guys, its so kind :)
5star service on landyzone as always :cool:

My P38 appriciates it :D
It has not been the most well maintained car, but i’ve done lots, lots to it. As deserved.

might treat the beast with AT KO2, it dosnt mess with air suspension does it? (Rave said only OEM tires/dimensions (i have 245/70/16))

and is the KO2 good in wintertime? (I might have throwaway winter tires, might…)

and i obviously want to drive some offroad cuz thats fun af :D
Click to expand...

One way valve is a good idea and cheap. I use an old Ezibleed kit with pressure from the front tyre to flush the modulator at the first steps in RAVE. Top up the reservoir between every step as it is lower than is looks and if air gets in it can be a total sod getting it out. I'd get 5L if it is that bad. Flush a litre through the modulator and then a litre through each brake line. If the lines haven't been replaced then check the rear ones before you start.
 
Halfords have a good deal on 5ltrs of dot4. Picking up some tomorrow.
Forget how much it was, just over £20 I think.
 
so after my understanding, a brake flush job is an hour job perhaps? i take 5-10 min in this time just to jack the car up and make it safe + all the wheels off etc so bleeding is easy.

I mistake an air leak from my FR damper actually so then i can investigate that... (LH drive)

I know a mate tried to bleed his brakes, he opened the brake nipple but nothing came out so he had to take the whole thing out.. his car missed dust caps tho..

So i will minimum need a bottle with a oneway valve to flush the brakes alone. + that handy thing to screw into reservoar would be quite nice so i wont need to fill it up all the time

Does the accumulator use alot of battery pumping? might i need to charge my battery up after a session of brake flushing?
huge 120ah 880ccu smth..

I am going to buy 5L of Bosch Dot 4 universal fluid
and a bottle with one way valve to bleed brakes etc,
I think for now i will only top up as normaly, but why is it a no no to get brake fluid level under minimum during bleeding? Theres fluid under minimum aswell :rolleyes:

Mines inbetween min-max whilst brakes are pressurized.

Is it just bcus some valves/intakes/outputs are right bellow minimum lvl and that will alow air to get dragged into the system? I suppose?
 
How does theese works anyhow??
I get it, you just plug it into a compressor.
But will this make it not needed to press the pedal? As one normally would with a normal bottle?
It just uses air and pressure magic and it just sucks out fluid from the bleed valve? Whilst not needing to use the pedals?

Can someone simplify the bleeding process for me?

Rave states i must close the bleed screw at the bottom of each stroke before i release the brake pedal. Surely this is not needed if i have a one way valve fitted????
Obviously a very, very small amount of brake fluid will go back into the system due to oneway valve is not right at the nipple.., but that remaining which will go back into the system, is fresh new fluid. so surely cant hurt?

appart from this i guess i just follow rave? but i must not care about the close screw at middle of brake stroke blah blah? As long as the brake fluid is clean and aint no air bubbles behind the oneway valve i guess?

I suppose air wont leak back trough a oneway valve:eek:

I am thinking to buy the one without air pressure, but maybe someone persuades me to buy the one with air? Price is not bad for any of theese pictured. like 10£ difference.
 

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The "air" one is a vacuum bottle. You hook it up and it "sucks" the fluid through. The other look to be a catch can only.
 
Marshall8hp said:
The "air" one is a vacuum bottle. You hook it up and it "sucks" the fluid through. The other look to be a catch can only.
Click to expand...
My question is should the OP be touching his brakes at all given his knowledge level. I know everyone has to learn but brakes?? I wonder if he knows someone with experience who could walk him through the process.:eek::)
 
Well if he wants do a full bleed, which would be the best way to go, follow the directions in the manual and forget the fancy kit. The best option is Mark’s pressure blended though, just a little expensive for a one off use.
 
Just follow RAVE. The expansion tank just unclips to give you more room to get at the nipples on the modulator. And you're right, if using a one way valve there's no need to nip the nipple back up each time. The modulator has lots of valves inside and it seems to pull air in for fun if you go too low. Give yourself a couple of hours and take your time and you'll be fine. You'll need a second person for some parts.

Charging the battery first is a good idea.
 
synchro said:
How does theese works anyhow??
I get it, you just plug it into a compressor.
But will this make it not needed to press the pedal? As one normally would with a normal bottle?
It just uses air and pressure magic and it just sucks out fluid from the bleed valve? Whilst not needing to use the pedals?

Can someone simplify the bleeding process for me?

Rave states i must close the bleed screw at the bottom of each stroke before i release the brake pedal. Surely this is not needed if i have a one way valve fitted????
Obviously a very, very small amount of brake fluid will go back into the system due to oneway valve is not right at the nipple.., but that remaining which will go back into the system, is fresh new fluid. so surely cant hurt?

appart from this i guess i just follow rave? but i must not care about the close screw at middle of brake stroke blah blah? As long as the brake fluid is clean and aint no air bubbles behind the oneway valve i guess?

I suppose air wont leak back trough a oneway valve:eek:

I am thinking to buy the one without air pressure, but maybe someone persuades me to buy the one with air? Price is not bad for any of theese pictured. like 10£ difference.
Click to expand...
You need to follow RAVE exactly, no simplification, no short cuts, your life depends on doing the job properly.
 
tomcat59alan said:
My question is should the OP be touching his brakes at all given his knowledge level. I know everyone has to learn but brakes?? I wonder if he knows someone with experience who could walk him through the process.:eek::)
Click to expand...

I can for a fact say, if this was a year back, i wouldn't even be wrenching on my car. Saves lots of money now, and its a good feeling fixing/servicing for sure, atleast if its neglected...

I'm confident in doing the brake fluid, i mean im not gonna put water or slushie into the brake lines :D (dot 4)

Sure its my first time, but i've got the manual, + as long as i do 1 bleed valve at a time, + check my min-max lvl at reservoar what can go wrong?

I don't know what knowledge level you think im at. I've done lots of things, even changed brake pads at the rear (i suppose it worked since im still here and not out in a ditch)

I obviously appreciate feedback tho but felt this was abit indirect, and at my age of 21, one could probably not expect much (working logistics), but hey, not every 21 yr old is the same skill wise o_O


But, i'd like to know why you doubt me @tomcat59alan :( Is it because i make so many threads? My age? Or me just questioning a brake bleed procedure? I obviously can just follow the manual, but in many of my problems, the manual has not been the easiest, or just the more correct way to do something.

Grrrrrr said:
Doubt it will be as cheap by the time they've posted it to Norway!
Click to expand...

I paid 50£ for 5L bosch dot 4 here :confused: :eek:
Bottle with one way valve 20£
30£ shipping from Island4x4

cheers
 
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