Air leak

[Chuck Wheeler]

Sounds like you found the Vacuum generator! If working properly it will
shut off when the vacuum reaches a "set point". If you have a vacuum leak
in the cruse control it will continue to vent air to make up the lost
vacuum. I replaced my cruse control with a Rostra Global Cruise when my
generator quit as they are not available any more. It worked with the
existing stalk control and speed sensor.

- Chuck Wheeler -
82 FC 31 SB
Fort Worth, TX


_____

From: WanderlodgeForum@yahoogroups.com
[mailto:WanderlodgeForum@yahoogroups.com] On Behalf Of Gardner Yeaw
Sent: Sunday, August 20, 2006 6:53 PM
To: WanderlodgeForum@yahoogroups.com
Subject: [WanderlodgeForum] Air leak



I have an air leak in the front of my 78FC33. Lying on the ground
and reaching up in the left front there is what looks like a
distribution valve. It has at least two thin black hoses attached
with screw on caps. When I shut off the coach it leaks for a few
minutes then stops. The brake tanks keep about 75 lbs of preasure,
but the step stops working.

There is a tube that is designed to have a rubber hose sliped over
it on one side of the valve, I can't see it, but that is where the
air is leaking from, It seemed odd that there would be a slip on
connection when all the others are the standard black tube with a
screw on connector.

Does anyone have any idea what this valve may be for? I had read
that the cruise control used air passing over a venturi to generate
vacuume, could this be it?

Thanks
Gardner
78FC33






[Non-text portions of this message have been removed]

[dthollis1961]

Gardner,

On my '78, what you are talking about was a manifold that sent air
to the steps, horns, tire inflator hose etc. There is a safety
valve on that manifold that shut the air supply off to these non-
essential accessories when air pressure drops to 65 pounds so your
brakes will still function . That's why your gauges stop dropping
at 65. Also on that manifold is the low air pressure warning
sensor. I replaced both the safety valve and the low air
sensor...one or both were leaking. Common parts and less than $10
each at the big truck store.

My 78 had an electric vacuum pump for the cruise mounted in the RF
compartment.

David Hollis 84 FC35 Springfield,IL


--- In WanderlodgeForum@yahoogroups.com, "Gardner Yeaw"
wrote:
>
> I have an air leak in the front of my 78FC33. Lying on the ground
> and reaching up in the left front there is what looks like a
> distribution valve. It has at least two thin black hoses attached
> with screw on caps. When I shut off the coach it leaks for a few
> minutes then stops. The brake tanks keep about 75 lbs of preasure,
> but the step stops working.
>
> There is a tube that is designed to have a rubber hose sliped
over
> it on one side of the valve, I can't see it, but that is where the
> air is leaking from, It seemed odd that there would be a slip on
> connection when all the others are the standard black tube with a
> screw on connector.
>
> Does anyone have any idea what this valve may be for? I had
read
> that the cruise control used air passing over a venturi to
generate
> vacuume, could this be it?
>
> Thanks
> Gardner
> 78FC33
>

[Gardner Yeaw]

Dave,
I will follow up on your info. I need to have the under carriage cleaned
so I see the color of the wires and determine where the leaks are (oil,
power steering, etc). Since I don’t plan to use the cruise control for now,
I will block the leak and see what happens. I wish there was a physical
location manual to find all of these little trick valves, etc. I think I
will take digital pictures and post them on the forum. Other members that
know what certain valves, solenoids do could add comments to make it easier
for others.

I determined that my horn problems are in the steering column where the
citrcuit is transferred from the rotating wheel to the horn circuit. If I
turn the wheel the horn works, but straight ahead it doesn’t. I am checking
in the parts manual to see what I need, but in the meantime I installed a
separate button for the horn to get through state inspection.

Gardner
78FC33


-----Original Message-----
From: WanderlodgeForum@yahoogroups.com
[mailto:WanderlodgeForum@yahoogroups.com]On Behalf Of dthollis1961
Sent: Sunday, August 20, 2006 9:34 PM
To: WanderlodgeForum@yahoogroups.com
Subject: [WanderlodgeForum] Re: Air leak

Gardner,

On my '78, what you are talking about was a manifold that sent air
to the steps, horns, tire inflator hose etc. There is a safety
valve on that manifold that shut the air supply off to these non-
essential accessories when air pressure drops to 65 pounds so your
brakes will still function . That's why your gauges stop dropping
at 65. Also on that manifold is the low air pressure warning
sensor. I replaced both the safety valve and the low air
sensor...one or both were leaking. Common parts and less than $10
each at the big truck store.

My 78 had an electric vacuum pump for the cruise mounted in the RF
compartment.

David Hollis 84 FC35 Springfield,IL

--- In WanderlodgeForum@yahoogroups.com
, "Gardner Yeaw"
wrote:
>
> I have an air leak in the front of my 78FC33. Lying on the ground
> and reaching up in the left front there is what looks like a
> distribution valve. It has at least two thin black hoses attached
> with screw on caps. When I shut off the coach it leaks for a few
> minutes then stops. The brake tanks keep about 75 lbs of preasure,
> but the step stops working.
>
> There is a tube that is designed to have a rubber hose sliped
over
> it on one side of the valve, I can't see it, but that is where the
> air is leaking from, It seemed odd that there would be a slip on
> connection when all the others are the standard black tube with a
> screw on connector.
>
> Does anyone have any idea what this valve may be for? I had
read
> that the cruise control used air passing over a venturi to
generate
> vacuume, could this be it?
>
> Thanks
> Gardner
> 78FC33
>



[Non-text portions of this message have been removed]

[Jeff Miller]

If your '78 has a mechanical (Ghast) vacuum pump in the back of the
compartment under the co-pilot's seat, this is not an
aspirator/vacuum-generator. If it is, look for vacuum leaks in the
cruise control as others have mentioned.

- Jeff Miller
in Holland, MI


--- In WanderlodgeForum@yahoogroups.com, "Gardner Yeaw"
wrote:
>
> I have an air leak in the front of my 78FC33. Lying on the ground
> and reaching up in the left front there is what looks like a
> distribution valve. It has at least two thin black hoses attached
> with screw on caps. When I shut off the coach it leaks for a few
> minutes then stops. The brake tanks keep about 75 lbs of preasure,
> but the step stops working.
>
> There is a tube that is designed to have a rubber hose sliped over
> it on one side of the valve, I can't see it, but that is where the
> air is leaking from, It seemed odd that there would be a slip on
> connection when all the others are the standard black tube with a
> screw on connector.
>
> Does anyone have any idea what this valve may be for? I had read
> that the cruise control used air passing over a venturi to generate
> vacuume, could this be it?
>
> Thanks
> Gardner
> 78FC33
>

[Gardner Yeaw]

Jeff,
I don't believe I have a pump, at least I have never heard it run
and there is nothing in the compartment. I will study the diagrams
and such and begin looking for the vacuume lines and cruise control
components. In the meantime I will seal up the leak and skip the
cruise control.

Gardner
78FC33

--- In WanderlodgeForum@yahoogroups.com, "Jeff Miller"
wrote:
>
> If your '78 has a mechanical (Ghast) vacuum pump in the back of the
> compartment under the co-pilot's seat, this is not an
> aspirator/vacuum-generator. If it is, look for vacuum leaks in the
> cruise control as others have mentioned.
>
> - Jeff Miller
> in Holland, MI
>
>
> --- In WanderlodgeForum@yahoogroups.com, "Gardner Yeaw"
> wrote:
> >
> > I have an air leak in the front of my 78FC33. Lying on the ground
> > and reaching up in the left front there is what looks like a
> > distribution valve. It has at least two thin black hoses attached
> > with screw on caps. When I shut off the coach it leaks for a few
> > minutes then stops. The brake tanks keep about 75 lbs of
preasure,
> > but the step stops working.
> >
> > There is a tube that is designed to have a rubber hose sliped
over
> > it on one side of the valve, I can't see it, but that is where
the
> > air is leaking from, It seemed odd that there would be a slip on
> > connection when all the others are the standard black tube with a
> > screw on connector.
> >
> > Does anyone have any idea what this valve may be for? I had
read
> > that the cruise control used air passing over a venturi to
generate
> > vacuume, could this be it?
> >
> > Thanks
> > Gardner
> > 78FC33
> >
>

[Stephen Birtles]

Gardner
is there a small screenned in portion inthe front bin if there is
look behind that It took me 2 years before I found mine just never
paid attention to the screened in box
Stephen 77fc35

--- In WanderlodgeForum@yahoogroups.com, "Gardner Yeaw"
wrote:
>
> Jeff,
> I don't believe I have a pump, at least I have never heard it run
> and there is nothing in the compartment. I will study the diagrams
> and such and begin looking for the vacuume lines and cruise control
> components. In the meantime I will seal up the leak and skip the
> cruise control.
>
> Gardner
> 78FC33
>
> --- In WanderlodgeForum@yahoogroups.com, "Jeff Miller"
> wrote:
> >
> > If your '78 has a mechanical (Ghast) vacuum pump in the back of the
> > compartment under the co-pilot's seat, this is not an
> > aspirator/vacuum-generator. If it is, look for vacuum leaks in the
> > cruise control as others have mentioned.
> >
> > - Jeff Miller
> > in Holland, MI
> >
> >
> > --- In WanderlodgeForum@yahoogroups.com, "Gardner Yeaw"
> > wrote:
> > >
> > > I have an air leak in the front of my 78FC33. Lying on the ground
> > > and reaching up in the left front there is what looks like a
> > > distribution valve. It has at least two thin black hoses attached
> > > with screw on caps. When I shut off the coach it leaks for a few
> > > minutes then stops. The brake tanks keep about 75 lbs of
> preasure,
> > > but the step stops working.
> > >
> > > There is a tube that is designed to have a rubber hose sliped
> over
> > > it on one side of the valve, I can't see it, but that is where
> the
> > > air is leaking from, It seemed odd that there would be a slip on
> > > connection when all the others are the standard black tube with a
> > > screw on connector.
> > >
> > > Does anyone have any idea what this valve may be for? I had
> read
> > > that the cruise control used air passing over a venturi to
> generate
> > > vacuume, could this be it?
> > >
> > > Thanks
> > > Gardner
> > > 78FC33
> > >
> >
>

[Gardner Yeaw]

Stephen,

You are correct, there is a pump behind the screen, however, it
is in a state of partial disassembly and has been disconnected. Back
to the drawing board.It is possable the air operated vacuume
generator was retro-fitted, or I just have a missing connection.
Looks like a little more digging is in order.

Thanks,
Gardner
78FC33

--- In WanderlodgeForum@yahoogroups.com, "Stephen Birtles"
wrote:
>
> Gardner
> is there a small screenned in portion inthe front bin if there is
> look behind that It took me 2 years before I found mine just never
> paid attention to the screened in box
> Stephen 77fc35
>
> --- In WanderlodgeForum@yahoogroups.com, "Gardner Yeaw"
> wrote:
> >
> > Jeff,
> > I don't believe I have a pump, at least I have never heard it
run
> > and there is nothing in the compartment. I will study the
diagrams
> > and such and begin looking for the vacuume lines and cruise
control
> > components. In the meantime I will seal up the leak and skip the
> > cruise control.
> >
> > Gardner
> > 78FC33
> >
> > --- In WanderlodgeForum@yahoogroups.com, "Jeff Miller"

> > wrote:
> > >
> > > If your '78 has a mechanical (Ghast) vacuum pump in the back
of the
> > > compartment under the co-pilot's seat, this is not an
> > > aspirator/vacuum-generator. If it is, look for vacuum leaks in
the
> > > cruise control as others have mentioned.
> > >
> > > - Jeff Miller
> > > in Holland, MI
> > >
> > >
> > > --- In WanderlodgeForum@yahoogroups.com, "Gardner Yeaw"

> > > wrote:
> > > >
> > > > I have an air leak in the front of my 78FC33. Lying on the
ground
> > > > and reaching up in the left front there is what looks like a
> > > > distribution valve. It has at least two thin black hoses
attached
> > > > with screw on caps. When I shut off the coach it leaks for a
few
> > > > minutes then stops. The brake tanks keep about 75 lbs of
> > preasure,
> > > > but the step stops working.
> > > >
> > > > There is a tube that is designed to have a rubber hose
sliped
> > over
> > > > it on one side of the valve, I can't see it, but that is
where
> > the
> > > > air is leaking from, It seemed odd that there would be a
slip on
> > > > connection when all the others are the standard black tube
with a
> > > > screw on connector.
> > > >
> > > > Does anyone have any idea what this valve may be for? I
had
> > read
> > > > that the cruise control used air passing over a venturi to
> > generate
> > > > vacuume, could this be it?
> > > >
> > > > Thanks
> > > > Gardner
> > > > 78FC33
> > > >
> > >
> >
>

[erniecarpet@...]

Terry, that would be great. I would like a couple of those babies- maybe
they will sell them in quantity?

Ernie Ekberg
83PT40
Livingston, Mt




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[erniecarpet@...]

Thanks, Ron, Terry Neal just called me and he will try the Detroit place in
Billings on Monday. The coach airs up, but I stopped for 15 minutes to get
propane and the air was down to 60, with the engine off.

Ernie Ekberg
83PT40
Livingston, Mt




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[Non-text portions of this message have been removed]

[erniecarpet@...]

Thanks Mike, I'll look in Bozeman, on Sat.

Ernie Ekberg
83PT40
Livingston, Mt




************************************** Get a sneak peek of the all-new AOL at
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[Non-text portions of this message have been removed]