Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Bob Fryer on November 03, 2018, 03:12:46 pm

Title: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: Bob Fryer on November 03, 2018, 03:12:46 pm
Hi,

Reading through the many post regarding the Heat/AC actuators I notice I'm having a simular problem that "Ducky1" had (posted about 9 months ago), no vacuum at the vacuum store ball.  I'm unable to find the vacuum pumps location in any of the manuals that I currently own. 

Question: can someone provide location of the vacuum pump for a 88 GV? 

Thanks Bob
Title: Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: craneman on November 03, 2018, 03:22:01 pm
I am not sure about yours but my '81 and '99 use an air venturi device to make the vacuum. Air pressure goes through a valve that creates suction on a port that goes to the can or ball.
Title: Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: jor on November 03, 2018, 04:00:13 pm
Here is a photo of where it is on a 93 225 and a photo of the pump itself. Might be similar. It was low down so if you lay on your back under the front end on the drivers side of a 93 you would be looking right at it.
jor
Title: Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: craneman on November 03, 2018, 04:10:26 pm
This is a photo of my '99 don't have a pic for the '81

obsolete vacuum generator (http://www.foreforums.com/index.php?topic=27357.msg223782#msg223782)
Title: Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: Old phart phred on November 03, 2018, 04:46:32 pm
It's not a pump, it's just a venturi fitting follow the hoses out of the ball to a black plastic piece with a 1.25" round top it will have 3 hoses connected and an exhaust port. Believe or not that's it. Compressed air line goes into bottom.
Title: Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: Chuck & Jeannie on November 03, 2018, 05:18:17 pm
Bob,

IF it turns out you have the electric vacuum pump like shown in JOR's post (above), then there may also be a vacuum controlled switch mounted on the firewall somewhere up above the pump.  This switch tells the pump when to come on, so if it fails...no vacuum.  See the post linked below for a photo:

Vacuum switch for dash AC controls. (http://www.foreforums.com/index.php?topic=34465.msg317867#msg317867)
Title: Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: red tractor on November 03, 2018, 08:45:02 pm
On our 84 ORED the park brake had to be released to get air to the venturi.
Title: Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: Protech Racing on November 03, 2018, 10:24:58 pm
 My 88 is the out side of the firewall  , right  inline with  the steering wheel .  Open the driver side hood and look down for 3 small air lines  going to a T type of housing.
Title: Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: Old phart phred on November 04, 2018, 01:25:56 am
On our 84 ORED the park brake had to be released to get air to the venturi.
Aha, mystery solved why it runs continuous sometimes, but doesn't drain the air tanks when parked. Thanks red tractor!
Title: Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)
Post by: Bob Fryer on November 04, 2018, 08:46:11 am
Thanks everyone!  I think "Old Phart Phred" id'd the one I have... will track the Venturi line to see if it's damaged.