Vacuum line

[patrick flowers]

Arch,

Try plugging the line and pulling a vacuum(using a mityvac or similar)
on the servo it's supposed to be connected to and see if you get air out
the duct. If not, it's a bad servo. If you do, break out the
maintenance manual to find the other end of that line. Pull the other
end off and plug it, then try to pull a vacuum on it. If you can't,
then replace the line, if you can.... You get the idea, right?

HTH,
Patrick

>
> GMCers
>
> Been working on the lady all day. There is a purple vacuum line going
> to the passenger side black box located between the "Positive battery
> terminal" and the under hood work light. With the ac on recirculate and
> on high there is no air coming out of that duct. I can blow and suck on that
> line with no resistance. Where is the problem? I also have no air coming
> out of the drivers side duct. I do have that big center duct open without
> the duct work on it. ( Thats the modification done to later models). Lots
> of good cold air out of that duct. AC seems to be working very well--
> return line sweating all the way back to compressor on a 78 degree day.
>
> Take Care
> Arch
- --
Patrick Flowers
Mailtoatrick

The GMC Motorhome Page
http://www.gmcmotorhome.com

 

[ron & gina]

Hi Arch,

Hey I'm still learning, But isn't that the recirc duck back to the blower ?
The one the net talks about opening up to increase flow back to blower for
better flow while in recirc mode? Should feel suction by floor duct in front
of pass seat, When in AC recirc mode. My 73 has little air flow thru that
suction duct. Thinking of doing that mod. on the flow back.

Ron&Gina
73 Pumpkin-Rose
Ft. Mohave, AZ.

- ----- Original Message -----
From:
To:
Sent: Sunday, May 07, 2000 7:12 PM
Subject: GMC: Vacuum line

> GMCers
>
> Been working on the lady all day. There is a purple vacuum line going
> to the passenger side black box located between the "Positive battery
> terminal" and the under hood work light. With the ac on recirculate and
> on high there is no air coming out of that duct. I can blow and suck on
that
> line with no resistance. Where is the problem? I also have no air coming
> out of the drivers side duct. I do have that big center duct open without
> the duct work on it. ( Thats the modification done to later models). Lots
> of good cold air out of that duct. AC seems to be working very well--
> return line sweating all the way back to compressor on a 78 degree day.
>
> Take Care
> Arch

 

[ron & gina]

Arch,

IIRC, I believe you can see the gate open on that duct from the inside,
might need a mirror

Ron&Gina
73 Pumpkin-Rose
Ft. Mohave, AZ.

- ----- Original Message -----
From:
To:
Sent: Monday, May 08, 2000 4:06 PM
Subject: Re: GMC: Vacuum line

> In a message dated 05/08/2000 5:03:51 PM Central Daylight Time,

>
> > Should feel suction by floor duct in front
> > of pass seat, When in AC recirc mode. My 73 has little air flow thru
that
> > suction duct. Thinking of doing that mod. on the flow back.
> >
> Ron
>
> Thanks. Think I may fire it up tonight and use my hand vacuum on
> it. I also found I can lower the output air temp by 8 degrees if I cover
> the outside air intake. It is not sealed but just some of it blocked off.
>
> Take Care
> Arch

 

[ron & gina]

Meant also to say that I also taped/restrict my fresh air intake, But
removed during last trip to Bay area needed more hot air that time. And
seemed to help the heater with tape removed? (more air, cause of restricted
duct return?

Ron&Gina
73 Pumpkin-Rose
Ft. Mohave, AZ.

- ----- Original Message -----
From: "Ron & Gina"
To:
Sent: Monday, May 08, 2000 4:25 PM
Subject: Re: GMC: Vacuum line

> Arch,
>
> IIRC, I believe you can see the gate open on that duct from the inside,
> might need a mirror
>
> Ron&Gina
> 73 Pumpkin-Rose
> Ft. Mohave, AZ.
>
> ----- Original Message -----
> From:
> To:
> Sent: Monday, May 08, 2000 4:06 PM
> Subject: Re: GMC: Vacuum line
>
>
> > In a message dated 05/08/2000 5:03:51 PM Central Daylight Time,

> >
> > > Should feel suction by floor duct in front
> > > of pass seat, When in AC recirc mode. My 73 has little air flow thru
> that
> > > suction duct. Thinking of doing that mod. on the flow back.
> > >
> > Ron
> >
> > Thanks. Think I may fire it up tonight and use my hand vacuum on
> > it. I also found I can lower the output air temp by 8 degrees if I cover
> > the outside air intake. It is not sealed but just some of it blocked
off.
> >
> > Take Care
> > Arch
>
>