Getting rid of air pockets after replacing the front brake disc pads

dmkAlex wrote:
> On Sep 30, 8:11 pm, Kevin Bottorff > wrote:
>> dmkAlex > wrote in news:1191196070.865996.122380@
>> 57g2000hsv.googlegroups.com:
>>
>>
>>
>>
>>
>>> When I opened up the caliper to replace the disc pad, a lot of the
>>> brake fluid was drained from the caliper's chamber when I squeezed the
>>> piston back in place. I notice that there was a air valve stub on the
>>> top of the inner caliper. At the time I didn't know what it was for.
>>> When I have put the disc/tire back to gether, I had to pump the brake
>>> about 5 minutes to get the brake fluide filling the system. I had to
>>> put in more than a bottle of new brake fluid.
>>> The brake still feel not as sensitive as it should. I guess that there
>>> was still air in the system. As I think, I think I will have to
>>> release the air that was traped in the upper part of the caliper by
>>> pressing the valve.
>>> My questions a
>>> Do I pump the brake before turning on agnition, or should it turn on
>>> the agnition first?
>>> I think I will press the air valve down while pumping it until fluid
>>> started to come out, right?
>>> Appreciate you input.
>>> Thanks.
>>> Alex
>> I am sorry, but you really don`t know enough about it to risk messing
>> with something as important as brakes. Have some one that knows exactly
>> what there doing check your brakes. something isnt right there. KB
>>
>> --
>> Thunder Snake #9
>> "Protect" your rights or "lose" them.- Hide quoted text -
>>
>> - Show quoted text -
>
> Kevin,
>
> Changing disc brake pad and rotar is a very simple job. I have done it
> in many of my cars.
>
> Some cars, the brake fluid flows back to the reservoir. This one is a
> relatively new car and the brake fluid is drained (leak) out from the
> caliper's chamber. I am pretty sure that's why Lexus put a air valve
> in the caliper to release the air from the upper chamber.
>
> Alex
>

NO brake fluid should have come out at all for a simple pad replacement,
unless you deliberately opened a bleeder while compressing the pistons.
It is a closed system so as you compress the pistons the fluid will be
forced into the reservoir on the master cylinder. If it came out
somewhere else you have a major problem.

Sounds like you removed the pistons and got air in the calipers. Now you
need to do a complete brake bleeding procedure on all 4 brakes to remove
the air. Toyotas usually can be done without a scan tool to cycle the
valves in the ABS. You just need to bleed them starting at the farthest
brake first.

--
Steve W.
Near Cooperstown, New York
NRA Member
Pacifism - The theory that if they'd fed
Jeffrey Dahmer enough human flesh,
he'd have become a vegan.

Don't be so arrogant man. What could go wrong? It sounds like he's
already driving the car and the brakes are working, do you think
they'll suddenly fail in an emergency? How?

Everyone has to start somewhere.



On Oct 1, 1:11 pm, Kevin Bottorff > wrote:

> I am sorry, but you really don`t know enough about it to risk messing
> with something as important as brakes. Have some one that knows exactly
> what there doing check your brakes. something isnt right there. KB
>
> --
> Thunder Snake #9
> "Protect" your rights or "lose" them.- Hide quoted text -
>
> - Show quoted text -

On Oct 1, 7:38 pm, wrote:
> Don't be so arrogant man. What could go wrong? It sounds like he's
> already driving the car and the brakes are working, do you think
> they'll suddenly fail in an emergency? How?
>
> Everyone has to start somewhere.
>

Not when this newbie is sharing the road with the rest of us. Just
because he was lucky enough to get this far doesn't guarantee
something won't blow apart on the first panic stop. Somethings need
so much to be right that it doesn't matter if feelings get hurt -
brakes come to mind.

I'm glad that this guy is getting a little flaming. Hopefully it will
motivate him to invest in either a real shop doing the work or at
least finding a good, experienced mentor.

Calvin

On Oct 2, 12:01 pm, Calvin > wrote:
> On Oct 1, 7:38 pm, wrote:
>
> > Don't be so arrogant man. What could go wrong? It sounds like he's
> > already driving the car and the brakes are working, do you think
> > they'll suddenly fail in an emergency? How?
>
> > Everyone has to start somewhere.
>
> Not when this newbie is sharing the road with the rest of us. Just
> because he was lucky enough to get this far doesn't guarantee
> something won't blow apart on the first panic stop. Somethings need
> so much to be right that it doesn't matter if feelings get hurt -
> brakes come to mind.
>
> I'm glad that this guy is getting a little flaming. Hopefully it will
> motivate him to invest in either a real shop doing the work or at
> least finding a good, experienced mentor.
>
> Calvin

For the benefit of those who had problem visualizing what I tried to
say, let me put it in chronological order and hope that it helps.

First, as a qualifier, we are talking about a 2005 Lexus GX470. Unlike
most of the American cars I have seen, the caliper of this car is
quite different.

Most caliper is one piece. This one has two halves.

The back half is mounted to the chassis of the car and the brake fluid
tube is connected to this half.

The front half is screwed in with 4 screws to the back half.

There is a hole, with gasket, connecting the front and back chambers
in the inside of the caliper. That's where the brake fluid travels
from the chamber in the back to the chamber in the front to create
pressure to the brake pistons.

In order to remove the brake disc and the rotor, I have to take the 4
screws and remove the front caliper from the back.
When I did that, brake fluid will leak out from the hole from the
chamber.

To give more space to accommodate the new disc pad I squeezed the
piston and more fluid leaked through the hole from the chamber.

After reinstalling the pad, rotor and the caliper, I filled the brake
fluid reservoir with a quart of new fluid and pumped the brake for 10
minutes to get fluid back in the system. The warning light system
indicates everything is fine.

The brakes are working but I do feel a little sponginess. That made
think which step I could be missing.

I recall that there is an air valve above the brake fluid tube in the
inside of the back caliper. The valve is covered with a rubber cup
like the way we have the screwed on cover to the tire stub.

So, I was guessing that, when I pumped the brake to force the fluid to
refill the chamber, there may be an air pocket inside the chamber. I
was thinking, maybe, I press down the air-valve while I pump the brake
again, the brake fluid will force the air out from the valve.

I post the question here to look for confirmation.

I was hoping that someone have experience with this model of car and
can give me some advise.

Of course, if you never touch a Lexus, it would be hard to visualize.

I hope the above have clarify some misunderstanding.

Alex

dmkAlex wrote:
> On Oct 2, 12:01 pm, Calvin > wrote:
>> On Oct 1, 7:38 pm, wrote:
>>
>>> Don't be so arrogant man. What could go wrong? It sounds like he's
>>> already driving the car and the brakes are working, do you think
>>> they'll suddenly fail in an emergency? How?
>>> Everyone has to start somewhere.
>> Not when this newbie is sharing the road with the rest of us. Just
>> because he was lucky enough to get this far doesn't guarantee
>> something won't blow apart on the first panic stop. Somethings need
>> so much to be right that it doesn't matter if feelings get hurt -
>> brakes come to mind.
>>
>> I'm glad that this guy is getting a little flaming. Hopefully it will
>> motivate him to invest in either a real shop doing the work or at
>> least finding a good, experienced mentor.
>>
>> Calvin
>
> For the benefit of those who had problem visualizing what I tried to
> say, let me put it in chronological order and hope that it helps.
>
> First, as a qualifier, we are talking about a 2005 Lexus GX470. Unlike
> most of the American cars I have seen, the caliper of this car is
> quite different.
>
> Most caliper is one piece. This one has two halves.
>
> The back half is mounted to the chassis of the car and the brake fluid
> tube is connected to this half.
>
> The front half is screwed in with 4 screws to the back half.
>
> There is a hole, with gasket, connecting the front and back chambers
> in the inside of the caliper. That's where the brake fluid travels
> from the chamber in the back to the chamber in the front to create
> pressure to the brake pistons.
>
> In order to remove the brake disc and the rotor, I have to take the 4
> screws and remove the front caliper from the back.
> When I did that, brake fluid will leak out from the hole from the
> chamber.
>
> To give more space to accommodate the new disc pad I squeezed the
> piston and more fluid leaked through the hole from the chamber.
>
> After reinstalling the pad, rotor and the caliper, I filled the brake
> fluid reservoir with a quart of new fluid and pumped the brake for 10
> minutes to get fluid back in the system. The warning light system
> indicates everything is fine.
>
> The brakes are working but I do feel a little sponginess. That made
> think which step I could be missing.
>
> I recall that there is an air valve above the brake fluid tube in the
> inside of the back caliper. The valve is covered with a rubber cup
> like the way we have the screwed on cover to the tire stub.
>
> So, I was guessing that, when I pumped the brake to force the fluid to
> refill the chamber, there may be an air pocket inside the chamber. I
> was thinking, maybe, I press down the air-valve while I pump the brake
> again, the brake fluid will force the air out from the valve.
>
> I post the question here to look for confirmation.
>
> I was hoping that someone have experience with this model of car and
> can give me some advise.
>
> Of course, if you never touch a Lexus, it would be hard to visualize.
>
> I hope the above have clarify some misunderstanding.
>
> Alex
>

I believe you did one step too many and shouldn't have taken apart the
two halves. Could be wrong, but didn't think a Saturn would be that
screwed up for doing brakes, makes no real sense.... The caliper should
have lifted off the rotor once the slider/mount bolts are out.

Now that you have opened it, you need to bleed the brakes.

That valve is a bleeder valve and must be loosened with a small socket
wrench or box end wrench to allow the air to bleed out of the caliper as
the pedal gets depressed. It then gets tightened as the pedal goes back
up and then the process is repeated. A clear hose stuck on the bleeder
going into a glass jar with some fluid in the bottom is sometimes used
so you can see the air coming out. This usually takes two people to do
and it might now need all 4 wheels bled to be safe. Especially if you
let the master go empty.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

Mike Romain wrote:
> dmkAlex wrote:
>
>> On Oct 2, 12:01 pm, Calvin > wrote:
>>
>>> On Oct 1, 7:38 pm, wrote:
>>>
>>>> Don't be so arrogant man. What could go wrong? It sounds like he's
>>>> already driving the car and the brakes are working, do you think
>>>> they'll suddenly fail in an emergency? How?
>>>> Everyone has to start somewhere.
>>>
>>> Not when this newbie is sharing the road with the rest of us. Just
>>> because he was lucky enough to get this far doesn't guarantee
>>> something won't blow apart on the first panic stop. Somethings need
>>> so much to be right that it doesn't matter if feelings get hurt -
>>> brakes come to mind.
>>>
>>> I'm glad that this guy is getting a little flaming. Hopefully it will
>>> motivate him to invest in either a real shop doing the work or at
>>> least finding a good, experienced mentor.
>>>
>>> Calvin
>>
>>
>> For the benefit of those who had problem visualizing what I tried to
>> say, let me put it in chronological order and hope that it helps.
>>
>> First, as a qualifier, we are talking about a 2005 Lexus GX470. Unlike
>> most of the American cars I have seen, the caliper of this car is
>> quite different.
>>
>> Most caliper is one piece. This one has two halves.
>>
>> The back half is mounted to the chassis of the car and the brake fluid
>> tube is connected to this half.
>>
>> The front half is screwed in with 4 screws to the back half.
>>
>> There is a hole, with gasket, connecting the front and back chambers
>> in the inside of the caliper. That's where the brake fluid travels
>> from the chamber in the back to the chamber in the front to create
>> pressure to the brake pistons.
>>
>> In order to remove the brake disc and the rotor, I have to take the 4
>> screws and remove the front caliper from the back.
>> When I did that, brake fluid will leak out from the hole from the
>> chamber.
>>
>> To give more space to accommodate the new disc pad I squeezed the
>> piston and more fluid leaked through the hole from the chamber.
>>
>> After reinstalling the pad, rotor and the caliper, I filled the brake
>> fluid reservoir with a quart of new fluid and pumped the brake for 10
>> minutes to get fluid back in the system. The warning light system
>> indicates everything is fine.
>>
>> The brakes are working but I do feel a little sponginess. That made
>> think which step I could be missing.
>>
>> I recall that there is an air valve above the brake fluid tube in the
>> inside of the back caliper. The valve is covered with a rubber cup
>> like the way we have the screwed on cover to the tire stub.
>>
>> So, I was guessing that, when I pumped the brake to force the fluid to
>> refill the chamber, there may be an air pocket inside the chamber. I
>> was thinking, maybe, I press down the air-valve while I pump the brake
>> again, the brake fluid will force the air out from the valve.
>>
>> I post the question here to look for confirmation.
>>
>> I was hoping that someone have experience with this model of car and
>> can give me some advise.
>>
>> Of course, if you never touch a Lexus, it would be hard to visualize.
>>
>> I hope the above have clarify some misunderstanding.
>>
>> Alex
>>
>
> I believe you did one step too many and shouldn't have taken apart the
> two halves. Could be wrong, but didn't think a Saturn would be that
> screwed up for doing brakes, makes no real sense.... The caliper should
> have lifted off the rotor once the slider/mount bolts are out.
>
> Now that you have opened it, you need to bleed the brakes.
>
> That valve is a bleeder valve and must be loosened with a small socket
> wrench or box end wrench to allow the air to bleed out of the caliper as
> the pedal gets depressed. It then gets tightened as the pedal goes back
> up and then the process is repeated. A clear hose stuck on the bleeder
> going into a glass jar with some fluid in the bottom is sometimes used
> so you can see the air coming out. This usually takes two people to do
> and it might now need all 4 wheels bled to be safe. Especially if you
> let the master go empty.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> (More Off Road album links at bottom of the view page)

yeah, sounds like a standard 2- or 4-piston caliper to me, and I don't
believe the halves are supposed to be separated... well, lesson learned
I hope and the OP should bleed the brakes again and watch for leaks.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On Oct 3, 4:56 pm, Mike Romain > wrote:
> dmkAlex wrote:
> > On Oct 2, 12:01 pm, Calvin > wrote:
> >> On Oct 1, 7:38 pm, wrote:
>
> >>> Don't be so arrogant man. What could go wrong? It sounds like he's
> >>> already driving the car and the brakes are working, do you think
> >>> they'll suddenly fail in an emergency? How?
> >>> Everyone has to start somewhere.
> >> Not when this newbie is sharing the road with the rest of us. Just
> >> because he was lucky enough to get this far doesn't guarantee
> >> something won't blow apart on the first panic stop. Somethings need
> >> so much to be right that it doesn't matter if feelings get hurt -
> >> brakes come to mind.
>
> >> I'm glad that this guy is getting a little flaming. Hopefully it will
> >> motivate him to invest in either a real shop doing the work or at
> >> least finding a good, experienced mentor.
>
> >> Calvin
>
> > For the benefit of those who had problem visualizing what I tried to
> > say, let me put it in chronological order and hope that it helps.
>
> > First, as a qualifier, we are talking about a 2005 Lexus GX470. Unlike
> > most of the American cars I have seen, the caliper of this car is
> > quite different.
>
> > Most caliper is one piece. This one has two halves.
>
> > The back half is mounted to the chassis of the car and the brake fluid
> > tube is connected to this half.
>
> > The front half is screwed in with 4 screws to the back half.
>
> > There is a hole, with gasket, connecting the front and back chambers
> > in the inside of the caliper. That's where the brake fluid travels
> > from the chamber in the back to the chamber in the front to create
> > pressure to the brake pistons.
>
> > In order to remove the brake disc and the rotor, I have to take the 4
> > screws and remove the front caliper from the back.
> > When I did that, brake fluid will leak out from the hole from the
> > chamber.
>
> > To give more space to accommodate the new disc pad I squeezed the
> > piston and more fluid leaked through the hole from the chamber.
>
> > After reinstalling the pad, rotor and the caliper, I filled the brake
> > fluid reservoir with a quart of new fluid and pumped the brake for 10
> > minutes to get fluid back in the system. The warning light system
> > indicates everything is fine.
>
> > The brakes are working but I do feel a little sponginess. That made
> > think which step I could be missing.
>
> > I recall that there is an air valve above the brake fluid tube in the
> > inside of the back caliper. The valve is covered with a rubber cup
> > like the way we have the screwed on cover to the tire stub.
>
> > So, I was guessing that, when I pumped the brake to force the fluid to
> > refill the chamber, there may be an air pocket inside the chamber. I
> > was thinking, maybe, I press down the air-valve while I pump the brake
> > again, the brake fluid will force the air out from the valve.
>
> > I post the question here to look for confirmation.
>
> > I was hoping that someone have experience with this model of car and
> > can give me some advise.
>
> > Of course, if you never touch a Lexus, it would be hard to visualize.
>
> > I hope the above have clarify some misunderstanding.
>
> > Alex
>
> I believe you did one step too many and shouldn't have taken apart the
> two halves. Could be wrong, but didn't think a Saturn would be that
> screwed up for doing brakes, makes no real sense.... The caliper should
> have lifted off the rotor once the slider/mount bolts are out.
>
> Now that you have opened it, you need to bleed the brakes.
>
> That valve is a bleeder valve and must be loosened with a small socket
> wrench or box end wrench to allow the air to bleed out of the caliper as
> the pedal gets depressed. It then gets tightened as the pedal goes back
> up and then the process is repeated. A clear hose stuck on the bleeder
> going into a glass jar with some fluid in the bottom is sometimes used
> so you can see the air coming out. This usually takes two people to do
> and it might now need all 4 wheels bled to be safe. Especially if you
> let the master go empty.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's - Gone to the rust pile...
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06http://www.imagestation.com/album/pictures.html?id=2115147590
> (More Off Road album links at bottom of the view page)- Hide quoted text -
>
> - Show quoted text -

Mike,

I really don't think I was able to remove the disc pad and the rotor
without removing the front half of the caliper. The back caliper was
solidly mounted to the chassis and the fluid hose was metal, not
flexible reinforced rubber found in most cars.

Anyway, I will follow your instruction this weekend to bleed the
excess air out of the chambers.

Thanks.

Alex

In article
. com>,
dmkAlex > wrote:

> For the benefit of those who had problem visualizing what I tried to
> say, let me put it in chronological order and hope that it helps.
>
> First, as a qualifier, we are talking about a 2005 Lexus GX470. Unlike
> most of the American cars I have seen, the caliper of this car is
> quite different.
>
> Most caliper is one piece. This one has two halves.
>
> The back half is mounted to the chassis of the car and the brake fluid
> tube is connected to this half.

That's a hose, not tube.

> The front half is screwed in with 4 screws to the back half.
>
> There is a hole, with gasket, connecting the front and back chambers
> in the inside of the caliper. That's where the brake fluid travels
> from the chamber in the back to the chamber in the front to create
> pressure to the brake pistons.
>
> In order to remove the brake disc and the rotor, I have to take the 4
> screws and remove the front caliper from the back.
> When I did that, brake fluid will leak out from the hole from the
> chamber.

Had you looked a little harder, you'd have seen to two bolts that
mount the whole caliper to the steering knuckle.
There was no need to split the caliper into two pieces.
Two bolts and the whole thing lifts off.

> To give more space to accommodate the new disc pad I squeezed the
> piston and more fluid leaked through the hole from the chamber.

I'm sure it did.

> After reinstalling the pad, rotor and the caliper, I filled the brake
> fluid reservoir with a quart of new fluid and pumped the brake for 10
> minutes to get fluid back in the system. The warning light system
> indicates everything is fine.
>
> The brakes are working but I do feel a little sponginess. That made
> think which step I could be missing.

The most basic one; knowing what you're doing.

> I recall that there is an air valve above the brake fluid tube in the
> inside of the back caliper. The valve is covered with a rubber cup
> like the way we have the screwed on cover to the tire stub.

A bleeder screw.

> So, I was guessing that, when I pumped the brake to force the fluid to
> refill the chamber, there may be an air pocket inside the chamber. I
> was thinking, maybe, I press down the air-valve while I pump the brake
> again, the brake fluid will force the air out from the valve.

Press down?

> I post the question here to look for confirmation.
>
> I was hoping that someone have experience with this model of car and
> can give me some advise.

Yellow pages, your best friend.

> Of course, if you never touch a Lexus, it would be hard to visualize.

Standard fixed caliper four piston brakes. Chevrolet had them
over 40 years ago.

> I hope the above have clarify some misunderstanding.

Indeed.

=========
==========
Mike Romain wrote in msg......
I believe you did one step too many and shouldn't have taken apart
the two halves. ? ?The caliper should have lifted off the rotor once
the slider/mount bolts are out.
==========
==========
Nate Nagel > wrotein msg:

yeah, sounds like a standard 2- or 4-piston caliper to me, and I
don't
believe the halves are supposed to be separated... ?well, lesson
learned
I hope and the OP should bleed the brakes again and watch for leaks.

nate
=======
=======

what they said.....ditto.......

and.......REPLACE THE CALIPER (or caliper..sss)
and bleed the system.



~:~
MarshMonster
~takes a toke.........and cranks down a bit harder
on the corvette caliper case half bolts.......gonna
stop this leak....i don't care WHO said they warp
when you break em in half.........another toke...
a sip of shroom tea.........mmmmmm........
good stuff~
~:~
=======

====
====

On Oct 3, 2:53?pm, dmkAlex > wrote:
> For the benefit of those who had problem visualizing what I tried to
> say, let me put it in chronological order and hope that it helps.
>
> First, as a qualifier, we are talking about a 2005 Lexus GX470. Unlike
> most of the American cars I have seen, the caliper of this car is
> quite different.
>
> Most caliper is one piece. This one has two halves.
>
> The back half is mounted to the chassis of the car and the brake fluid
> tube is connected to this half.
>
> The front half is screwed in with 4 screws to the back half.
>
> There is a hole, with gasket, connecting the front and back chambers
> in the inside of the caliper. That's where the brake fluid travels
> from the chamber in the back to the chamber in the front to create
> pressure to the brake pistons.
>
> In order to remove the brake disc and the rotor, I have to take the 4
> screws and remove the front caliper from the back.
> When I did that, brake fluid will leak out from the hole from the
> chamber.
>
> To give more space to accommodate the new disc pad I squeezed the
> piston and more fluid leaked through the hole from the chamber.
>
> After reinstalling the pad, rotor and the caliper, I filled the brake
> fluid reservoir with a quart of new fluid and pumped the brake for 10
> minutes to get fluid back in the system. The warning light system
> indicates everything is fine.
>
> The brakes are working but I do feel a little sponginess. That made
> think which step I could be missing.
>
> I recall that there is an air valve above the brake fluid tube in the
> inside of the back caliper. The valve is covered with a rubber cup
> like the way we have the screwed on cover to the tire stub.
>
> So, I was guessing that, when I pumped the brake to force the fluid to
> refill the chamber, there may be an air pocket inside the chamber. I
> was thinking, maybe, I press down the air-valve while I pump the brake
> again, the brake fluid will force the air out from the valve.
>
> I post the question here to look for confirmation.
>
> I was hoping that someone have experience with this model of car and
> can give me some advise.
>
> Of course, if you never touch a Lexus, it would be hard to visualize.
>
> I hope the above have clarify some misunderstanding.
>
> Alex- Hide quoted text -
>
> - Show quoted text -

=======
=======

is it what i'm smoke'n.......or did this dudes grammer and
sentence composition get markedly better as this conversation
progressed............


~:~
marsh
~takes another toke.........sips his crownroyal.....
looks at the op's first post....looks at the above post.......
fk it....must be the smoke, why would ANYONE.....
hide the fact they could converse......... ~
~:~