Re: Dash Vent System

Jumpnjoe59 · Post by **Jumpnjoe59** » Sat Sep 14, 2019 12:01 pm

'
So I it seems I may have a plumbing issue and maybe a vacuum pump issue. Right now I need to resolve the plumbing issue. Anyone have knowledge on where to start my investigation. When I set the air flow to upper/lower the system seems to work fine. I can actually watch the actuator move under the dash and feel the air begin to blow and it holds a vacuum. When I switch to upper, defrost, or recirculation the vacuum is lost and the actuator moves back up and I have no air flow.
Thx,
Joe,1997 Saraha 3550, 3126/300, 6 Sp'

TD · Post by TD » Sat Sep 14, 2019 12:57 pm

'Joe,

When there is no vacuum, the system defaults to defrost, all air goes
to the windshield. That position should not require any vacuum.
Re-circulation should require the most vacuum. In any case, from what
you described earlier, your pump is toast, so replace the pump and
then you should be able to pull enough vacuum to hear where the leak
is coming from. Or you can put a fog/smoke machine on it and you will
easily be able to see where the leaks are.

John
'95 Safari Serengeti 38ft, Cummins C8.3-300, Allison
6spd

On 9/14/19, jumpnjoe59@... [Safarifriends]
wrote:

>
>
> So I it seems I may have a plumbing issue and maybe a vacuum pump issue.
> Right now I need to resolve the plumbing issue. Anyone have knowledge on
> where to start my investigation. When I set the air flow to upper/lower the
> system seems to work fine. I can actually watch the actuator move under the
> dash and feel the air begin to blow and it holds a vacuum. When I switch to
> upper, defrost, or recirculation the vacuum is lost and the actuator moves
> back up and I have no air flow.
>
>
> Thx,
>
>
> Joe,1997 Saraha 3550, 3126/300, 6 Sp
>

'

Gary Smith · Post by **Gary Smith** » Sat Sep 14, 2019 1:25 pm

'Joe,I found these worked perfectly for my 1998 Sahara as well as my 2000 Trek.
https://www.amazon.com/gp/product/B00UAX1JSO/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Gary'98 Sahara 3006 300CAT
'

astrnmrtom · Post by **astrnmrtom** » Sat Sep 14, 2019 2:20 pm

'This should provide some options:
https://www.amazon.com/s?k=12v+miniature+vacuum+pump&ref=nb_sb_noss

Tom Masterson1998 Serengeti 3706300HP Cat, Allison 3060'

Jumpnjoe59 · Post by **Jumpnjoe59** » Sat Sep 14, 2019 5:41 pm

'Thanks again for all rsponses. I have ordered a pump and will see what that brings.'

Sarah George · Post by **Sarah George** » Tue Sep 17, 2019 12:14 pm

'Received the new vacuum pump, https://preview.tinyurl.com/yyxq3p4a , don't know how long this will work but for now it is working as I think it should. I have had this MH for two years and have never heard the pump shut off!! The defroster still does not blow air. I will have to investigate that another time. Thanks to all for the suggestions and input.

Joe, 1997 Sahara 3550, 3126/300hp, 6 spd'

James Exler · Post by **James Exler** » Tue Sep 17, 2019 12:22 pm

'

Joe,

Are you aware that my drawing for the dash A/C is in the files section and includes both electrical and vacuum?

Jim Exler, Nampa, ID

On 9/17/2019 7:14 PM, Sarah George jumpnjoe59@... [Safarifriends] wrote:

Received the new vacuum pump,
https://preview.tinyurl.com/yyxq3p4a , don't know how long this will work but for now it is working as I think it should. I have had this MH for two years and have never heard the pump shut off!! The defroster still does not blow air. I will have to investigate
that another time. Thanks to all for the suggestions and input.

Joe, 1997 Sahara 3550, 3126/300hp, 6 spd

Virus-free.
www.avg.com

'

Jumpnjoe59 · Post by **Jumpnjoe59** » Wed Sep 18, 2019 5:30 am

'Yes...I have looked at it in the past. I just have trouble putting the drawings to the physcal location within the MH. I will play some more this weekend. You have a bunch of great documentation out there....I think I speak for all when I say we appreciate all the time and effort you guys put into the documentation that is out there.
Joe'

Billy Massey · Post by **Billy Massey** » Tue Sep 24, 2019 5:26 am

' I just replaced my defroster duct hoses. Originals were rotted to pieces. Yours probably are too. Billy
'98 Serengeti
Central Texas From: Safarifriends@yahoogroups.com [mailto:Safarifriends@yahoogroups.com]
Sent: Tuesday, September 17, 2019 8:15 PM
To: Safarifriends@yahoogroups com
Subject: [Safarifriends] Re: Dash Vent System
Received the new vacuum pump, https://preview.tinyurl.com/yyxq3p4a , don't know how long this will work but for now it is working as I think it should. I have had this MH for two years and have never heard the pump shut off!! The defroster still does not blow air. I will have to investigate that another time. Thanks to all for the suggestions and input.

Joe, 1997 Sahara 3550, 3126/300hp, 6 spd '

Bill Edwards · Post by **Bill Edwards** » Tue Sep 24, 2019 9:23 am

' Vent hoses in mine are like new, both coaches. There was an excess of hose from all points. I removed 20+ feet improving flow considerably.

Sent from Yahoo Mail for iPad

On Tuesday, September 24, 2019, 12:26 PM, 'Billy Massey' bdub@... [Safarifriends] wrote:
I just replaced my defroster duct hoses. Originals were rotted to pieces. Yours probably are too. Billy
'98 Serengeti
Central Texas From: Safarifriends@yahoogroups.com [mailto:Safarifriends@yahoogroups.com]
Sent: Tuesday, September 17, 2019 8:15 PM
To: Safarifriends@yahoogroups com
Subject: [Safarifriends] Re: Dash Vent System
Received the new vacuum pump, https://preview.tinyurl.com/yyxq3p4a , don't know how long this will work but for now it is working as I think it should. I have had this MH for two years and have never heard the pump shut off!! The defroster still does not blow air. I will have to investigate that another time. Thanks to all for the suggestions and input.

Joe, 1997 Sahara 3550, 3126/300hp, 6 spd

'