Air leaking from front when brakes applied

[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

> >

> >

> > __________________________________________________

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> >

>