Air leaking from front when brakes applied

[gregory O]

could be "double check valve" ? anyway I dont believe it is designed to
continualy release air while service brake is applied. I think it directs the
service psi to the spring psi.
90 psi + 90 psi = 90 psi
but mechanical force of 1,000 psi and another mechanical source of 1,000 psi =
2,000 psi which is where the shoes crack.

My higheel is done and on the bus. folds up to 14 foot high then lifts
automaticaly to 19.5 foot tall
I will post pict later, parade is Sunday
Greg
94ptca


--- In WanderlodgeForum@yahoogroups.com, Curt Sprenger wrote:
>
> Greg,
> Good information for sure, thanks! Do you know the BlueBird name for that
> compounding valve?
>
> Curt Sprenger
> 1987 PT38 8V92 "MacAttack Racing"
> Anaheim Hills, CA
>
>
>
> On Sun, Nov 1, 2009 at 7:21 PM, gregory O wrote:
>
> >
> >
> > it is the anti compouning valve blowing air ?? when the spring brake is
> > left pushing (park brake on) and someone pushes on the service brakes, the
> > valve proportions the pressure working the cams on the axle that hold the
> > spring brakes so there is not too much pressure on the shoes. if the valve
> > is crapped out you get broken shoes with no sign of heat that made the
> > cracks .
> >
> >
> > to keep from giving a lecture then getting a lecture from the mods, check
> > out page 27 of Bendix
handbook<http://www.wsafc.org/WSFMA/Shared%20Docu...e%20H\
andbook.pdf>
> >
> >
> >
> >
> >
http://www.wsafc.org/WSFMA/Shared%20Docu...ook.p\
df
> >
> > here is a good video of the principles of
AB<http://www.youtube.com/watch?v=qJa5-_ExsBE>
> > without much of the new safety crap confusing the process it is from 1967
> >
> > http://www.youtube.com/watch?v=qJa5-_ExsBE
> >
> > Greg
> > 94ptca
> >
> >
> >
> > --- In WanderlodgeForum@yahoogroups.com, Curt Sprenger
> > wrote:
> > >
> > > Paul,
> > >
> > > What you found and determined does not seem right. Post pictures if you
> > can.
> > > I looked under our coach this afternoon. I see a 1/8" plastic air line to
> > > the cylinder that rotates down the driving light. Above that area on the
> > > bottom of the frame rail there are some copper and plastic air lines.
> > None
> > > are open as you describe.
> > >
> > > Curt Sprenger
> > > 1987 PT38 8V92 "MacAttack Racing"
> > > Anaheim Hills, CA
> > >
> > >
> > >
> > > On Sat, Oct 31, 2009 at 2:35 PM, P & D audvid1@ wrote:
> > >
> > > >
> > > >
> > > > Thanks you all for the assistance. Got some help today and we climbed
> > > > under coach and found a ¼ air line on the driver side front right
> > behind the
> >
> > > > fog lights that when you step on the brakes air comes out of that line
> > and
> > > > as soon as let off it stops. After looking at drawings and trying to
> > figure
> > > > out where the other end should be connected, by accident we discovered
> > that
> > > > if you plug the hose, the coach emergency brake released. (Good thing
> > we
> > > > are on a level lot) and if you un plug it, the emergency brakes stay
> > > > locked. Then we tried it with the emergency brake released and no air
> > came
> > > > out, so I think it is releasing the air bypassing the emergency brake
> > so as
> > > > to not release the emergency brake.
> > > >
> > > >
> > > >
> > > > Hope all that made sense, but it appears that is normal operation,
> > although
> > > > I never recall hearing that noise before when I stepped on the brake.
> > > >
> > > >
> > > >
> > > > Thanks again for all the help
> > > >
> > > >
> > > >
> > > > Paul & Debbie Potter
> > > >
> > > > Hesperia CA
> > > >
> > > > 1987 PT 38
> > > >
> > > > Hotel California II
> > > >
> > > >
> > > >
> > > > *From:* WanderlodgeForum@yahoogroups.com [mailto:
> > > > WanderlodgeForum@yahoogroups.com] *On Behalf Of *Wayne Kotila
> > > > *Sent:* Monday, October 26, 2009 1:56 PM
> > > > *To:* WanderlodgeForum@yahoogroups.com
> > > > *Subject:* Re: [WanderlodgeForum] Air leaking from front when brakes
> > > > applied
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > Did you check the rubber hoses to the front brakes? When you step on
> > the
> > > > brake pedal air pressure applies your front brakes so you will have air
> > > > pressure in the supply hoses to until you take your foot off the brake
> > > > pedal. Sometimes from age those hoses will start leaking where the end
> > is
> > > > crimped on the hose and if you need to replace them, a farm supply
> > store
> > > > will carry high pressure hydraulic hose in different diameters and
> > lengths
> > > > and have different end adapters to convert the end connector to what
> > you
> > > > need. You should be able to get a new hose and adapters if needed for
> > under
> > > > $20.00.
> > > >
> > > > Wayne
> > > >
> > > > 1996 WB42
> > > >
> > > >
> > > > ------------------------------
> > > >
> > > > *From:* ppotter14950 audvid1@
> > > > *To:* WanderlodgeForum@yahoogroups.com
> >
> > > > *Sent:* Sun, October 25, 2009 9:38:25 PM
> > > > *Subject:* [WanderlodgeForum] Air leaking from front when brakes
> > applied
> > > >
> > > >
> > > >
> > > > Hi there
> > > >
> > > > Today while finishing up Air Force One supplemental braking install for
> > > > towed vehicle, had engine off and when applied brakes to test Air Force
> > One
> > > > and while pedal was depressed there was a constant air leak up front
> > around
> > > > the left front area, but could not find it. Any suggestions on where it
> > > > might be, will work on taking front driver side panel open and looking
> > in
> > > > there, but it is so tight in there and i dont know what i am looking
> > for so
> > > > any suggestions would be appreciated.
> > > >
> > > > Thanks
> > > >
> > > > Paul & Debbie Potter
> > > > 87PT40 - Hotel California II
> > > > Hesperia CA
> > > >
> > > >
> > > > __________________________________________________
> > > > Do You Yahoo!?
> > > > Tired of spam? Yahoo! Mail has the best spam protection around
> > > > http://mail.yahoo.com
> > > >
> > > >
> > > >
> > >
> >
> >
>

[P & D]

Wow, that is a bunch of good material, but I may still be
confused about the anti-compound valve, is it working correctly or not working
correctly.

To add more to this mystery, it was just in the shop and they
had to replace 2 stripped auto slack adjusters to the brakes, could this have been
because too much pressure was applied with both the parking and regular brakes applied
at the same time?  Also when I plugged the hose, the spring brake released, is
that what you want it to do if you have applied the brakes. 

Thanks for all the info too

Paul

87pt38

Hesperia CA

From:
WanderlodgeForum@yahoogroups.com [mailto:WanderlodgeForum@yahoogroups.com] On
Behalf Of gregory O

Sent: Sunday, November 01, 2009 7:21 PM

To: WanderlodgeForum@yahoogroups.com

Subject: [WanderlodgeForum] Re: Air leaking from front when brakes
applied

it is the anti compouning valve blowing air ?? when the spring brake
is left pushing (park brake on) and someone pushes on the service brakes, the
valve proportions the pressure working the cams on the axle that hold the
spring brakes so there is not too much pressure on the shoes. if the valve is
crapped out you get broken shoes with no sign of heat that made the cracks .





to keep from giving a lecture then getting a lecture from the mods,
check
out page 27 of Bendix handbook





http://www.wsafc.org/WSFMA/Shared%20Docu...ndbook.pdf



here is a good video of
the principles of AB without much of the new safety crap
confusing the process it is from 1967



http://www.youtube.com/watch?v=qJa5-_ExsBE



Greg

94ptca





--- In WanderlodgeForum@yahoogroups.com, Curt Sprenger
wrote:

>

> Paul,

>

> What you found and determined does not seem right. Post pictures if you
can.

> I looked under our coach this afternoon. I see a 1/8" plastic air
line to

> the cylinder that rotates down the driving light. Above that area on the

> bottom of the frame rail there are some copper and plastic air lines. None

> are open as you describe.

>

> Curt Sprenger

> 1987 PT38 8V92 "MacAttack Racing"

> Anaheim Hills, CA

>

>

>

> On Sat, Oct 31, 2009 at 2:35 PM, P & D audvid1@... wrote:

>

> >

> >

> > Thanks you all for the assistance. Got some help today and we climbed

> > under coach and found a ¼ air line on the driver side front right
behind the

> > fog lights that when you step on the brakes air comes out of that
line and

> > as soon as let off it stops. After looking at drawings and trying to
figure

> > out where the other end should be connected, by accident we
discovered that

> > if you plug the hose, the coach emergency brake released. (Good thing
we

> > are on a level lot) and if you un plug it, the emergency brakes stay

> > locked. Then we tried it with the emergency brake released and no air
came

> > out, so I think it is releasing the air bypassing the emergency brake
so as

> > to not release the emergency brake.

> >

> >

> >

> > Hope all that made sense, but it appears that is normal operation,
although

> > I never recall hearing that noise before when I stepped on the brake.

> >

> >

> >

> > Thanks again for all the help

> >

> >

> >

> > Paul & Debbie Potter

> >

> > Hesperia CA

> >

> > 1987 PT 38

> >

> > Hotel California II

> >

> >

> >

> > *From:* WanderlodgeForum@yahoogroups.com [mailto:

> > WanderlodgeForum@yahoogroups.com] *On Behalf Of *Wayne Kotila

> > *Sent:* Monday, October 26, 2009 1:56 PM

> > *To:* WanderlodgeForum@yahoogroups.com

> > *Subject:* Re: [WanderlodgeForum] Air leaking from front when brakes

> > applied

> >

> >

> >

> >

> >

> > Did you check the rubber hoses to the front brakes? When you step on
the

> > brake pedal air pressure applies your front brakes so you will have
air

> > pressure in the supply hoses to until you take your foot off the
brake

> > pedal. Sometimes from age those hoses will start leaking where the
end is

> > crimped on the hose and if you need to replace them, a farm supply
store

> > will carry high pressure hydraulic hose in different diameters and
lengths

> > and have different end adapters to convert the end connector to what
you

> > need. You should be able to get a new hose and adapters if needed for
under

> > $20.00.

> >

> > Wayne

> >

> > 1996 WB42

> >

> >

> > ------------------------------

> >

> > *From:* ppotter14950 audvid1@...

> > *To:* WanderlodgeForum@yahoogroups.com

> > *Sent:* Sun, October 25, 2009 9:38:25 PM

> > *Subject:* [WanderlodgeForum] Air leaking from front when brakes
applied

> >

> >

> >

> > Hi there

> >

> > Today while finishing up Air Force One supplemental braking install
for

> > towed vehicle, had engine off and when applied brakes to test Air
Force One

> > and while pedal was depressed there was a constant air leak up front
around

> > the left front area, but could not find it. Any suggestions on where
it

> > might be, will work on taking front driver side panel open and
looking in

> > there, but it is so tight in there and i dont know what i am looking
for so

> > any suggestions would be appreciated.

> >

> > Thanks

> >

> > Paul & Debbie Potter

> > 87PT40 - Hotel California II

> > Hesperia CA

> >

> >

> > __________________________________________________

> > Do You Yahoo!?

> > Tired of spam? Yahoo! Mail has the best spam protection around

> > http://mail.yahoo.com

> >

> >

> >

>

[gregory O]

slack adjusters on the drive axle got damaged? I believe tcompounding cauld
damegd the slack adjusters. the drive is the axle with the park brakes (drive
axle has four tires)( Tag has one each side).
Greg
94ptca
--- In WanderlodgeForum@yahoogroups.com, "P & D" wrote:
>
> Wow, that is a bunch of good material, but I may still be confused about the
> anti-compound valve, is it working correctly or not working correctly.
>
>
>
> To add more to this mystery, it was just in the shop and they had to replace
> 2 stripped auto slack adjusters to the brakes, could this have been because
> too much pressure was applied with both the parking and regular brakes
> applied at the same time? Also when I plugged the hose, the spring brake
> released, is that what you want it to do if you have applied the brakes.
>
>
>
> Thanks for all the info too
>
>
>
> Paul
>
> 87pt38
>
> Hesperia CA
>
>
>
> From: WanderlodgeForum@yahoogroups.com
> [mailto:WanderlodgeForum@yahoogroups.com] On Behalf Of gregory O
> Sent: Sunday, November 01, 2009 7:21 PM
> To: WanderlodgeForum@yahoogroups.com
> Subject: [WanderlodgeForum] Re: Air leaking from front when brakes applied
>
>
>
>
>
> it is the anti compouning valve blowing air ?? when the spring brake is
> left pushing (park brake on) and someone pushes on the service brakes, the
> valve proportions the pressure working the cams on the axle that hold the
> spring brakes so there is not too much pressure on the shoes. if the valve
> is crapped out you get broken shoes with no sign of heat that made the
> cracks .
>
>
> to keep from giving a lecture then getting a lecture from the mods, check
> <http://www.wsafc.org/WSFMA/Shared%20Docu...ke%20Handb
> ook.pdf> out page 27 of Bendix handbook
>
>
> http://www.wsafc.org/WSFMA/Shared%20Docu...e%20Handbo
> ok.pdf
>
> here is a good video of <http://www.youtube.com/watch?v=qJa5-_ExsBE> the
> principles of AB without much of the new safety crap confusing the process
> it is from 1967
>
> http://www.youtube.com/watch?v=qJa5-_ExsBE
>
> Greg
> 94ptca
>
>
> --- In WanderlodgeForum@yahoogroups.com, Curt Sprenger
> wrote:
> >
> > Paul,
> >
> > What you found and determined does not seem right. Post pictures if you
> can.
> > I looked under our coach this afternoon. I see a 1/8" plastic air line to
> > the cylinder that rotates down the driving light. Above that area on the
> > bottom of the frame rail there are some copper and plastic air lines. None
> > are open as you describe.
> >
> > Curt Sprenger
> > 1987 PT38 8V92 "MacAttack Racing"
> > Anaheim Hills, CA
> >
> >
> >
> > On Sat, Oct 31, 2009 at 2:35 PM, P & D audvid1@ wrote:
> >
> > >
> > >
> > > Thanks you all for the assistance. Got some help today and we climbed
> > > under coach and found a ¼ air line on the driver side front right
> behind the
> > > fog lights that when you step on the brakes air comes out of that line
> and
> > > as soon as let off it stops. After looking at drawings and trying to
> figure
> > > out where the other end should be connected, by accident we discovered
> that
> > > if you plug the hose, the coach emergency brake released. (Good thing we
> > > are on a level lot) and if you un plug it, the emergency brakes stay
> > > locked. Then we tried it with the emergency brake released and no air
> came
> > > out, so I think it is releasing the air bypassing the emergency brake so
> as
> > > to not release the emergency brake.
> > >
> > >
> > >
> > > Hope all that made sense, but it appears that is normal operation,
> although
> > > I never recall hearing that noise before when I stepped on the brake.
> > >
> > >
> > >
> > > Thanks again for all the help
> > >
> > >
> > >
> > > Paul & Debbie Potter
> > >
> > > Hesperia CA
> > >
> > > 1987 PT 38
> > >
> > > Hotel California II
> > >
> > >
> > >
> > > *From:* WanderlodgeForum@yahoogroups.com [mailto:
> > > WanderlodgeForum@yahoogroups.com] *On Behalf Of *Wayne Kotila
> > > *Sent:* Monday, October 26, 2009 1:56 PM
> > > *To:* WanderlodgeForum@yahoogroups.com
> > > *Subject:* Re: [WanderlodgeForum] Air leaking from front when brakes
> > > applied
> > >
> > >
> > >
> > >
> > >
> > > Did you check the rubber hoses to the front brakes? When you step on the
> > > brake pedal air pressure applies your front brakes so you will have air
> > > pressure in the supply hoses to until you take your foot off the brake
> > > pedal. Sometimes from age those hoses will start leaking where the end
> is
> > > crimped on the hose and if you need to replace them, a farm supply store
> > > will carry high pressure hydraulic hose in different diameters and
> lengths
> > > and have different end adapters to convert the end connector to what you
> > > need. You should be able to get a new hose and adapters if needed for
> under
> > > $20.00.
> > >
> > > Wayne
> > >
> > > 1996 WB42
> > >
> > >
> > > ------------------------------
> > >
> > > *From:* ppotter14950 audvid1@
> > > *To:* WanderlodgeForum@yahoogroups.com
> > > *Sent:* Sun, October 25, 2009 9:38:25 PM
> > > *Subject:* [WanderlodgeForum] Air leaking from front when brakes applied
> > >
> > >
> > >
> > > Hi there
> > >
> > > Today while finishing up Air Force One supplemental braking install for
> > > towed vehicle, had engine off and when applied brakes to test Air Force
> One
> > > and while pedal was depressed there was a constant air leak up front
> around
> > > the left front area, but could not find it. Any suggestions on where it
> > > might be, will work on taking front driver side panel open and looking
> in
> > > there, but it is so tight in there and i dont know what i am looking for
> so
> > > any suggestions would be appreciated.
> > >
> > > Thanks
> > >
> > > Paul & Debbie Potter
> > > 87PT40 - Hotel California II
> > > Hesperia CA
> > >
> > >
> > > __________________________________________________
> > > Do You Yahoo!?
> > > Tired of spam? Yahoo! Mail has the best spam protection around
> > > http://mail.yahoo.com
> > >
> > >
> > >
> >
>

[gregory O]

--- In WanderlodgeForum@yahoogroups.com, "gregory O" wrote:
>
>
> slack adjusters on the drive axle got damaged? I believe tcompounding cauld
damegd the slack adjusters. the drive is the axle with the park brakes (drive
axle has four tires)( Tag has one each side).
> Greg
> 94ptca
> --- In WanderlodgeForum@yahoogroups.com, "P & D" wrote:
> >
> > Wow, that is a bunch of good material, but I may still be confused about the
Paul, it kind of makes sense that ;if the service brake is pushed while the
spring brake blatter is empty (spring pushing on the brake pad) air will be also
sent to the spring brake blatter to lift its force off of the shoe which is now
feeling the service brake force?????? But I have no idea of what it should do
and how the air is evacuated once again when you release the service brake I
would check with an expert shop



>> Also when I plugged the hose, the spring brake
> > released, is that what you want it to do if you have applied the brakes.
> >
> >
> >
> > Thanks for all the info too
> >
> >
> >
> > Paul
> >
> > 87pt38
> >
> > Hesperia CA
> >
> >
> >
> > From: WanderlodgeForum@yahoogroups.com
> > [mailto:WanderlodgeForum@yahoogroups.com] On Behalf Of gregory O
> > Sent: Sunday, November 01, 2009 7:21 PM
> > To: WanderlodgeForum@yahoogroups.com
> > Subject: [WanderlodgeForum] Re: Air leaking from front when brakes applied
> >
> >
> >
> >
> >
> > it is the anti compouning valve blowing air ?? when the spring brake is
> > left pushing (park brake on) and someone pushes on the service brakes, the
> > valve proportions the pressure working the cams on the axle that hold the
> > spring brakes so there is not too much pressure on the shoes. if the valve
> > is crapped out you get broken shoes with no sign of heat that made the
> > cracks .
> >
> >
> > to keep from giving a lecture then getting a lecture from the mods, check
> > <http://www.wsafc.org/WSFMA/Shared%20Docu...ke%20Handb
> > ook.pdf> out page 27 of Bendix handbook
> >
> >
> > http://www.wsafc.org/WSFMA/Shared%20Docu...e%20Handbo
> > ok.pdf
> >
> > here is a good video of <http://www.youtube.com/watch?v=qJa5-_ExsBE> the
> > principles of AB without much of the new safety crap confusing the process
> > it is from 1967
> >
> > http://www.youtube.com/watch?v=qJa5-_ExsBE
> >
> > Greg
> > 94ptca
> >
> >
> > --- In WanderlodgeForum@yahoogroups.com, Curt Sprenger
> > wrote:
> > >
> > > Paul,
> > >
> > > What you found and determined does not seem right. Post pictures if you
> > can.
> > > I looked under our coach this afternoon. I see a 1/8" plastic air line to
> > > the cylinder that rotates down the driving light. Above that area on the
> > > bottom of the frame rail there are some copper and plastic air lines. None
> > > are open as you describe.
> > >
> > > Curt Sprenger
> > > 1987 PT38 8V92 "MacAttack Racing"
> > > Anaheim Hills, CA
> > >
> > >
> > >
> > > On Sat, Oct 31, 2009 at 2:35 PM, P & D audvid1@ wrote:
> > >
> > > >
> > > >
> > > > Thanks you all for the assistance. Got some help today and we climbed
> > > > under coach and found a ¼ air line on the driver side front right
> > behind the
> > > > fog lights that when you step on the brakes air comes out of that line
> > and
> > > > as soon as let off it stops. After looking at drawings and trying to
> > figure
> > > > out where the other end should be connected, by accident we discovered
> > that
> > > > if you plug the hose, the coach emergency brake released. (Good thing we
> > > > are on a level lot) and if you un plug it, the emergency brakes stay
> > > > locked. Then we tried it with the emergency brake released and no air
> > came
> > > > out, so I think it is releasing the air bypassing the emergency brake so
> > as
> > > > to not release the emergency brake.
> > > >
> > > >
> > > >
> > > > Hope all that made sense, but it appears that is normal operation,
> > although
> > > > I never recall hearing that noise before when I stepped on the brake.
> > > >
> > > >
> > > >
> > > > Thanks again for all the help
> > > >
> > > >
> > > >
> > > > Paul & Debbie Potter
> > > >
> > > > Hesperia CA
> > > >
> > > > 1987 PT 38
> > > >
> > > > Hotel California II
> > > >
> > > >
> > > >
> > > > *From:* WanderlodgeForum@yahoogroups.com [mailto:
> > > > WanderlodgeForum@yahoogroups.com] *On Behalf Of *Wayne Kotila
> > > > *Sent:* Monday, October 26, 2009 1:56 PM
> > > > *To:* WanderlodgeForum@yahoogroups.com
> > > > *Subject:* Re: [WanderlodgeForum] Air leaking from front when brakes
> > > > applied
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > Did you check the rubber hoses to the front brakes? When you step on the
> > > > brake pedal air pressure applies your front brakes so you will have air
> > > > pressure in the supply hoses to until you take your foot off the brake
> > > > pedal. Sometimes from age those hoses will start leaking where the end
> > is
> > > > crimped on the hose and if you need to replace them, a farm supply store
> > > > will carry high pressure hydraulic hose in different diameters and
> > lengths
> > > > and have different end adapters to convert the end connector to what you
> > > > need. You should be able to get a new hose and adapters if needed for
> > under
> > > > $20.00.
> > > >
> > > > Wayne
> > > >
> > > > 1996 WB42
> > > >
> > > >
> > > > ------------------------------
> > > >
> > > > *From:* ppotter14950 audvid1@
> > > > *To:* WanderlodgeForum@yahoogroups.com
> > > > *Sent:* Sun, October 25, 2009 9:38:25 PM
> > > > *Subject:* [WanderlodgeForum] Air leaking from front when brakes applied
> > > >
> > > >
> > > >
> > > > Hi there
> > > >
> > > > Today while finishing up Air Force One supplemental braking install for
> > > > towed vehicle, had engine off and when applied brakes to test Air Force
> > One
> > > > and while pedal was depressed there was a constant air leak up front
> > around
> > > > the left front area, but could not find it. Any suggestions on where it
> > > > might be, will work on taking front driver side panel open and looking
> > in
> > > > there, but it is so tight in there and i dont know what i am looking for
> > so
> > > > any suggestions would be appreciated.
> > > >
> > > > Thanks
> > > >
> > > > Paul & Debbie Potter
> > > > 87PT40 - Hotel California II
> > > > Hesperia CA
> > > >
> > > >
> > > > __________________________________________________
> > > > Do You Yahoo!?
> > > > Tired of spam? Yahoo! Mail has the best spam protection around
> > > > http://mail.yahoo.com
> > > >
> > > >
> > > >
> > >
> >
>

[Curt Sprenger]

Paul,
Do this test...Parking brake set to PARK...get air brake pressure to max...shut off the engine or auxiliary air compressor...step on the service brake pedal...does air expel?..air expelling is good.

Repeat stepping on the service brake pedal...until air stops expelling...air brake gauge should be at or below 90 psi...no air expelling is good.


Test complete, system is working.  

Greg, you agree?

Curt Sprenger
1987 PT38 8V92 "MacAttack Racing"
Anaheim Hills, CA

On Mon, Nov 2, 2009 at 7:13 PM, P & D <"audvid1@gte.net"> wrote:

 

Wow, that is a bunch of good material, but I may still be
confused about the anti-compound valve, is it working correctly or not working
correctly.

 

To add more to this mystery, it was just in the shop and they
had to replace 2 stripped auto slack adjusters to the brakes, could this have been
because too much pressure was applied with both the parking and regular brakes applied
at the same time?  Also when I plugged the hose, the spring brake released, is
that what you want it to do if you have applied the brakes. 

 

Thanks for all the info too

 

Paul

87pt38

Hesperia CA

 

From:
"WanderlodgeForum@yahoogroups.com" [mailto:"WanderlodgeForum@yahoogroups.com"] On
Behalf Of gregory O

Sent: Sunday, November 01, 2009 7:21 PM

To: "WanderlodgeForum@yahoogroups.com"

Subject: [WanderlodgeForum] Re: Air leaking from front when brakes
applied

 

 

it is the anti compouning valve blowing air ??  when the spring brake
is left pushing (park brake on) and someone pushes on the service brakes, the
valve proportions the  pressure working the cams on the axle that hold the
spring brakes so there is not too much pressure on the shoes. if the valve is
crapped out you get broken shoes with no sign of heat that made the cracks .





to keep from giving a lecture  then getting a lecture from the mods, 
check
out page 27  of  Bendix handbook 





http://www.wsafc.org/WSFMA/Shared%20Docu...ndbook.pdf



here is a good video of
the principles  of AB  without much of the new safety crap
confusing the process it is from 1967



http://www.youtube.com/watch?v=qJa5-_ExsBE



Greg

94ptca





--- In "WanderlodgeForum@yahoogroups.com", Curt Sprenger
wrote:

>

> Paul,

>

> What you found and determined does not seem right. Post pictures if you
can.

> I looked under our coach this afternoon. I see a 1/8" plastic air
line to

> the cylinder that rotates down the driving light. Above that area on the

> bottom of the frame rail there are some copper and plastic air lines. None

> are open as you describe.

>

> Curt Sprenger

> 1987 PT38 8V92 "MacAttack Racing"

> Anaheim Hills, CA

>

>

>

> On Sat, Oct 31, 2009 at 2:35 PM, P & D audvid1@... wrote:

>

> >

> >

> > Thanks you all for the assistance. Got some help today and we climbed

> > under coach and found a ¼ air line on the driver side front right
behind the

> > fog lights that when you step on the brakes air comes out of that
line and

> > as soon as let off it stops. After looking at drawings and trying to
figure

> > out where the other end should be connected, by accident we
discovered that

> > if you plug the hose, the coach emergency brake released. (Good thing
we

> > are on a level lot) and if you un plug it, the emergency brakes stay

> > locked. Then we tried it with the emergency brake released and no air
came

> > out, so I think it is releasing the air bypassing the emergency brake
so as

> > to not release the emergency brake.

> >

> >

> >

> > Hope all that made sense, but it appears that is normal operation,
although

> > I never recall hearing that noise before when I stepped on the brake.

> >

> >

> >

> > Thanks again for all the help

> >

> >

> >

> > Paul & Debbie Potter

> >

> > Hesperia CA

> >

> > 1987 PT 38

> >

> > Hotel California II

> >

> >

> >

> > *From:* "WanderlodgeForum@yahoogroups.com" [mailto:

> > "WanderlodgeForum@yahoogroups.com"] *On Behalf Of *Wayne Kotila

> > *Sent:* Monday, October 26, 2009 1:56 PM

> > *To:* "WanderlodgeForum@yahoogroups.com"

> > *Subject:* Re: [WanderlodgeForum] Air leaking from front when brakes

> > applied

> >

> >

> >

> >

> >

> > Did you check the rubber hoses to the front brakes? When you step on
the

> > brake pedal air pressure applies your front brakes so you will have
air

> > pressure in the supply hoses to until you take your foot off the
brake

> > pedal. Sometimes from age those hoses will start leaking where the
end is

> > crimped on the hose and if you need to replace them, a farm supply
store

> > will carry high pressure hydraulic hose in different diameters and
lengths

> > and have different end adapters to convert the end connector to what
you

> > need. You should be able to get a new hose and adapters if needed for
under

> > $20.00.

> >

> > Wayne

> >

> > 1996 WB42

> >

> >

> > ------------------------------

> >

> > *From:* ppotter14950 audvid1@...

> > *To:* "WanderlodgeForum@yahoogroups.com"

> > *Sent:* Sun, October 25, 2009 9:38:25 PM

> > *Subject:* [WanderlodgeForum] Air leaking from front when brakes
applied

> >

> >

> >

> > Hi there

> >

> > Today while finishing up Air Force One supplemental braking install
for

> > towed vehicle, had engine off and when applied brakes to test Air
Force One

> > and while pedal was depressed there was a constant air leak up front
around

> > the left front area, but could not find it. Any suggestions on where
it

> > might be, will work on taking front driver side panel open and
looking in

> > there, but it is so tight in there and i dont know what i am looking
for so

> > any suggestions would be appreciated.

> >

> > Thanks

> >

> > Paul & Debbie Potter

> > 87PT40 - Hotel California II

> > Hesperia CA

> >

> >

> > __________________________________________________

> > Do You Yahoo!?

> > Tired of spam? Yahoo! Mail has the best spam protection around

> > http://mail.yahoo.com

> >

> >

> >

>

[P & D]

That is what it is doing, parking brake on and full of air, when
I step on brake pedal, I hear air expelling from hose.  I had never heard that
before (it probably was doing it)

I did not run air down to see if it stopped, but if I turn park
brake off (push knob in) then there is no air expelled from hose.

I am starting to think that is normal?

Paul

87PT38 – Hotel California II

Hesperia CA

From:
WanderlodgeForum@yahoogroups.com [mailto:WanderlodgeForum@yahoogroups.com] On
Behalf Of Curt Sprenger

Sent: Tuesday, November 03, 2009 6:24 AM

To: WanderlodgeForum@yahoogroups.com

Subject: Re: [WanderlodgeForum] Re: Air leaking from front when brakes
applied

Paul,

Do this test...Parking brake set to PARK...get air brake pressure to max...shut
off the engine or auxiliary air compressor...step on the service brake
pedal...does air expel?..air expelling is good.



Repeat stepping on the service brake pedal...until air stops expelling...air
brake gauge should be at or below 90 psi...no air expelling is good.



Test complete, system is working.



Greg, you agree?



Curt Sprenger

1987 PT38 8V92 "MacAttack Racing"

Anaheim Hills, CA

On Mon, Nov 2, 2009 at 7:13 PM, P & D <"audvid1@gte.net"> wrote:

Wow, that is a
bunch of good material, but I may still be confused about the anti-compound
valve, is it working correctly or not working correctly.

To add more to
this mystery, it was just in the shop and they had to replace 2 stripped auto
slack adjusters to the brakes, could this have been because too much pressure
was applied with both the parking and regular brakes applied at the same
time? Also when I plugged the hose, the spring brake released, is that
what you want it to do if you have applied the brakes.

Thanks for all
the info too

Paul

87pt38

Hesperia CA

From: "WanderlodgeForum@yahoogroups.com" [mailto:"WanderlodgeForum@yahoogroups.com"]
On Behalf Of gregory O

Sent: Sunday, November 01, 2009 7:21 PM

To: "WanderlodgeForum@yahoogroups.com"

Subject: [WanderlodgeForum] Re: Air leaking from front when brakes
applied

it is the anti compouning valve blowing air
?? when the spring brake is left pushing (park brake on) and someone
pushes on the service brakes, the valve proportions the pressure working
the cams on the axle that hold the spring brakes so there is not too much
pressure on the shoes. if the valve is crapped out you get broken shoes with no
sign of heat that made the cracks .





to keep from giving a lecture then getting a lecture from the mods,
check out page 27 of Bendix handbook





http://www.wsafc.org/WSFMA/Shared%20Docu...ndbook.pdf



here is a good video of the principles of AB without much of
the new safety crap confusing the process it is from 1967



http://www.youtube.com/watch?v=qJa5-_ExsBE



Greg

94ptca





--- In "WanderlodgeForum@yahoogroups.com",
Curt Sprenger wrote:

>

> Paul,

>

> What you found and determined does not seem right. Post pictures if you
can.

> I looked under our coach this afternoon. I see a 1/8" plastic air
line to

> the cylinder that rotates down the driving light. Above that area on the

> bottom of the frame rail there are some copper and plastic air lines. None

> are open as you describe.

>

> Curt Sprenger

> 1987 PT38 8V92 "MacAttack Racing"

> Anaheim Hills, CA

>

>

>

> On Sat, Oct 31, 2009 at 2:35 PM, P & D audvid1@... wrote:

>

> >

> >

> > Thanks you all for the assistance. Got some help today and we climbed

> > under coach and found a ¼ air line on the driver side front right
behind the

> > fog lights that when you step on the brakes air comes out of that
line and

> > as soon as let off it stops. After looking at drawings and trying to
figure

> > out where the other end should be connected, by accident we
discovered that

> > if you plug the hose, the coach emergency brake released. (Good thing
we

> > are on a level lot) and if you un plug it, the emergency brakes stay

> > locked. Then we tried it with the emergency brake released and no air
came

> > out, so I think it is releasing the air bypassing the emergency brake
so as

> > to not release the emergency brake.

> >

> >

> >

> > Hope all that made sense, but it appears that is normal operation,
although

> > I never recall hearing that noise before when I stepped on the brake.

> >

> >

> >

> > Thanks again for all the help

> >

> >

> >

> > Paul & Debbie Potter

> >

> > Hesperia CA

> >

> > 1987 PT 38

> >

> > Hotel California II

> >

> >

> >

> > *From:* "WanderlodgeForum@yahoogroups.com" [mailto:

> > "WanderlodgeForum@yahoogroups.com"]
*On Behalf Of *Wayne Kotila

> > *Sent:* Monday, October 26, 2009 1:56 PM

> > *To:* "WanderlodgeForum@yahoogroups.com"

> > *Subject:* Re: [WanderlodgeForum] Air leaking from front when brakes

> > applied

> >

> >

> >

> >

> >

> > Did you check the rubber hoses to the front brakes? When you step on
the

> > brake pedal air pressure applies your front brakes so you will have
air

> > pressure in the supply hoses to until you take your foot off the
brake

> > pedal. Sometimes from age those hoses will start leaking where the
end is

> > crimped on the hose and if you need to replace them, a farm supply
store

> > will carry high pressure hydraulic hose in different diameters and
lengths

> > and have different end adapters to convert the end connector to what
you

> > need. You should be able to get a new hose and adapters if needed for
under

> > $20.00.

> >

> > Wayne

> >

> > 1996 WB42

> >

> >

> > ------------------------------

> >

> > *From:* ppotter14950 audvid1@...

> > *To:* "WanderlodgeForum@yahoogroups.com"

> > *Sent:* Sun, October 25, 2009 9:38:25 PM

> > *Subject:* [WanderlodgeForum] Air leaking from front when brakes
applied

> >

> >

> >

> > Hi there

> >

> > Today while finishing up Air Force One supplemental braking install
for

> > towed vehicle, had engine off and when applied brakes to test Air
Force One

> > and while pedal was depressed there was a constant air leak up front
around

> > the left front area, but could not find it. Any suggestions on where
it

> > might be, will work on taking front driver side panel open and
looking in

> > there, but it is so tight in there and i dont know what i am looking
for so

> > any suggestions would be appreciated.

> >

> > Thanks

> >

> > Paul & Debbie Potter

> > 87PT40 - Hotel California II

> > Hesperia CA

> >

> >

> > __________________________________________________

> > Do You Yahoo!?

> > Tired of spam? Yahoo! Mail has the best spam protection around

> > http://mail.yahoo.com

> >

> >

> >

>

[Don Bradner]

I think you would find that, if you blocked that hose, you couldn't set the
parking brake at all.

I know just enough about this to be dangerous, so take this as a general thought
rather than expert opinion. It is based on having replaced my parking valve and
looking at the drawiings of how it works.

There are 3 ports on the parking valve. Air source, Air delivery, and Air
exhaust. Its "normal" at rest position (pushed by a spring) would have air
running from source to delivery and spring brake applied.

When you push in and overcome that spring, air pressure keeps it closed with air
running from source to delivery, which holds the spring brake off. If air
pressure drops below the spring value, the switch pops to its resting position.

When the air is allowed to exhaust, another valve in the system opens, called a
Quick Release valve. The line running to the dash is not large enough to truly
exhaust the air quickly from the chambers - that happens at the QR valve.

When you step on the brakes, I'm guessing the QR-valve expels additional air and
you get expelling air out to the exhaust.

When you block the exhaust, the air now coming in opens the valve allowing air
to pass to the parking brake, thus releasing it.

On my coach, the exhaust line runs out through the dash, and I did not trace it,
but it makes sense that it would go down somewhere in front. This line is not
required, but otherwise you get more air noise in the cab.

On 11/3/2009 at 4:26 PM P & D wrote:

>That is what it is doing, parking brake on and full of air, when I step
>on brake pedal, I hear air expelling from hose. I had never heard that
>before (it probably was doing it)
>
>
>
>I did not run air down to see if it stopped, but if I turn park brake off
>(push knob in) then there is no air expelled from hose.
>
>
>
>I am starting to think that is normal?