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Topic: Vacuum Pump Location for Heat/AC Actuators (1988 GV) (Read 587 times) previous topic - next topic

Vacuum Pump Location for Heat/AC Actuators (1988 GV)

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
1986 Grand Villa
Model: 3600 ORED
Truck Maker: Oshkosh
Truck Model: V-917-2
Engine: 3208-T-250

Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)

Reply #1 –
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.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)

Reply #2 –
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
93 225
95 300
97 270
99 320

Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)

Reply #3 –
This is a photo of my '99 don't have a pic for the '81

obsolete vacuum generator
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)

Reply #4 –
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.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)

Reply #5 –
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.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)

Reply #6 –
On our 84 ORED the park brake had to be released to get air to the venturi.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)

Reply #7 –
 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.

Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)

Reply #8 –
Quote from: red tractor –
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!
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Vacuum Pump Location for Heat/AC Actuators (1988 GV)

Reply #9 –
Thanks everyone!  I think "Old Phart Phred" id'd the one I have... will track the Venturi line to see if it's damaged. 
1986 Grand Villa
Model: 3600 ORED
Truck Maker: Oshkosh
Truck Model: V-917-2
Engine: 3208-T-250