Brake Loss After Hard Cornering

[stupidcar]

Guys,

My Persona Elegance 1.6 AT with front discs and rear drums.
Brake pedal went all the way after every hard cornering, giving me a scare but after I stepped it one time, it will be back to normal.
Hard cornering as in a sharp T-junction turn to the right for example.
But Ulu Yam is alright since its progressive, not sudden change.
I am going to bleed and change the fluids this Sunday but I am not sure if it will solve the problem.

Appreciate someone who has experienced this to comment.

 

[DanzEterna]

brake servo giving signs that is gonna kong soon?

 

[ken yeang]

bubble in the system?

 

[gunnerzz]

Guys,

My Persona Elegance 1.6 AT with front discs and rear drums.
Brake pedal went all the way after every hard cornering, giving me a scare but after I stepped it one time, it will be back to normal.
Hard cornering as in a sharp T-junction turn to the right for example.
But Ulu Yam is alright since its progressive, not sudden change.
I am going to bleed and change the fluids this Sunday but I am not sure if it will solve the problem.

Appreciate someone who has experienced this to comment.

sounds like the servo is leaking.the diapharm to be exact.
there are repair kit if u want to diy.

 

[stupidcar]

sounds like the servo is leaking.the diapharm to be exact.
there are repair kit if u want to diy.

Is it the one under the under the brake master cylinder?
I think I see its leaking.
Damn it. Warranty no more.

---------- Post added at 12:25 PM ---------- 6 hour anti-bump limit - Previous post was at 12:24 PM ----------

bubble in the system?

Lets see what happens after Sunday. Gonna bleed and change fluids.

---------- Post added at 12:26 PM ---------- 6 hour anti-bump limit - Previous post was at 12:25 PM ----------

brake servo giving signs that is gonna kong soon?

but its been quite long. Lats year I have no idea because I never hard corner it before.

___________________________________________________

Nobody experienced this before?

 

[vr2turbo]

Is it the one under the under the brake master cylinder?
I think I see its leaking.
Damn it. Warranty no more.

---------- Post added at 12:25 PM ---------- 6 hour anti-bump limit - Previous post was at 12:24 PM ----------



Lets see what happens after Sunday. Gonna bleed and change fluids.

---------- Post added at 12:26 PM ---------- 6 hour anti-bump limit - Previous post was at 12:25 PM ----------



but its been quite long. Lats year I have no idea because I never hard corner it before.

___________________________________________________

Nobody experienced this before?

Servo is the Big black round thing where your brake pump and reservoir is attached to. If that is leaking I recommend you get that fixed before you bleed and change fluid. New and clean fluid it may leak even more.
Check also you brake pump

 

[stupidcar]

Servo is the Big black round thing where your brake pump and reservoir is attached to. If that is leaking I recommend you get that fixed before you bleed and change fluid. New and clean fluid it may leak even more.
Check also you brake pump

Sunday will take a good look at it.

 

[gunnerzz]

Sunday will take a good look at it.

if its leaking fluid then the master cylinder seal is leaking.
remove it and take it apart.
there will.ne a rod with spring and rubber seal.
u have a choice of buying a complete kit or replace the seal only.

however do check the inside wall of the cylinder.
if there is significant wear then new seal wont help or it wont last long.

on the seal,buy the best seal u can afford.
there are cheap2 one.
last time i uses the cheap seal and it fail after less than a year.
then buy the expensive one.few years oso no leak.
different between the 2 that i exp is the good quality one is super hard to fit but if u know the trick,its super easy.

 

[stupidcar]

if its leaking fluid then the master cylinder seal is leaking.
remove it and take it apart.
there will.ne a rod with spring and rubber seal.
u have a choice of buying a complete kit or replace the seal only.

however do check the inside wall of the cylinder.
if there is significant wear then new seal wont help or it wont last long.

on the seal,buy the best seal u can afford.
there are cheap2 one.
last time i uses the cheap seal and it fail after less than a year.
then buy the expensive one.few years oso no leak.
different between the 2 that i exp is the good quality one is super hard to fit but if u know the trick,its super easy.

Buy back OEM then?

 

[gunnerzz]

Buy back OEM then?

thats the best bet.
with cheaper alternative its like a gamble esp on critical part.
however,only a handful of shop carry oe part.
for seal,famous brand is sanyco of something like that.

if u want to exp some diy then u can ask the shop for the best seal they have.
this way u save money on part.

 

[jerrysiow]

Sunday will take a good look at it.

Bro, better you check it today. This is brake system, your vehicle able to stop in time is depending on it.

 

[stupidcar]

Ok. VR2 has consulted me. The brake pedals there, reservoir and master cylinder all not leaking.
Just the reservoir flexes.

 

[gunnerzz]

Ok. VR2 has consulted me. The brake pedals there, reservoir and master cylinder all not leaking.
Just the reservoir flexes.

flexes?
how does it flex?
i can only imagine the rubber seal it seats on is loose.

 

[vr2turbo]

if its leaking fluid then the master cylinder seal is leaking.
remove it and take it apart.
there will.ne a rod with spring and rubber seal.
u have a choice of buying a complete kit or replace the seal only.

however do check the inside wall of the cylinder.
if there is significant wear then new seal wont help or it wont last long.

on the seal,buy the best seal u can afford.
there are cheap2 one.
last time i uses the cheap seal and it fail after less than a year.
then buy the expensive one.few years oso no leak.
different between the 2 that i exp is the good quality one is super hard to fit but if u know the trick,its super easy.

Nowadays the quality not good, made of aluminum or some soft alloy. Once leak usually the walls will be worn too....

---------- Post added at 08:44 PM ---------- 6 hour anti-bump limit - Previous post was at 08:42 PM ----------

Ok. VR2 has consulted me. The brake pedals there, reservoir and master cylinder all not leaking.
Just the reservoir flexes.

The reservoir will have slight movement one, depending on which type....


This one sits on rubber seal will have movement


This one clamp on, no movement

 

[gunnerzz]

Nowadays the quality not good, made of aluminum or some soft alloy. Once leak usually the walls will be worn too....

---------- Post added at 08:44 PM ---------- 6 hour anti-bump limit - Previous post was at 08:42 PM ----------



The reservoir will have slight movement one, depending on which type....


This one sits on rubber seal will have movement


This one clamp on, no movement

movement is normal right?
mine has small movement but no leak and no loss of brake pressure.

 

[vr2turbo]

movement is normal right?
mine has small movement but no leak and no loss of brake pressure.

Sitting on rubber seals one will have slight movement and is normal.....

 

[stupidcar]

Yesterday did change fluids and bled them all 4 corners.
Just a tad bit firmer pedal feel. But tried a hard corner, the pedal went all in as well. Have to step second time to have brakes again.
Really confused.

 

[vr2turbo]

Yesterday did change fluids and bled them all 4 corners.
Just a tad bit firmer pedal feel. But tried a hard corner, the pedal went all in as well. Have to step second time to have brakes again.
Really confused.

Why only in corner? First time hear this problem......

 

[stupidcar]

Why only in corner? First time hear this problem......

Have no idea.....The reservoir wasn't underfilled as well.

 

[Kopi]

for older proton (wira/satria/putra), this problem is usually caused by the hose that connects between the servo body to intake plenum. there are valves (old proton have 2 valve) inside the hose that regulates air into the servo and reserve air pressure in the servo. The first time pedal pressed, the valve(s) may be opening when it should be closed causing air in the servo being pumped into the intake instead of building pressure up from intake into the servo and the first floor triggered the valve to close on second flooring of the brake pedal. not sure if persona hose has 2 or 1 valve.

Note : PLEASE BUY ORIGINAL HOSE. I observed the cheaper 3rd party product is VERY NOT GOOD AND VERY HAZARDOUS (swelling, leak, broken valves...)