HVAC Problem

[lennyrebel]

My friends 96 H1 has no AC or Heater working . I told him I would ask the experts. Someone suggested vacuum lines. Any help would be appreciated. Thanks The Rebel

[ssgharkness020147]

First of all we would need to know if he has the updated HVAC system. So, are the HVAC controls the knobs or the "sliders". If he has the knobs it is the newer system, which I can help you with. The knob system is in fact vacuum controled, my guess would be the vacuum pump is not working any longer. Does he get defrost? If he gets defrost and nothing else (he may get some A/C from the vents) the pump itself is shot. Does he have access to a vacuum guage? If so tell him to pull the white line off of the wastegate solenoid, start the truck and measure for vacuum. He should get at least 18 hg in. If the pump is shot it will probably be more like 10.

[lennyrebel]

Thanks For your quick reply Carey, I'll be talking to him tonight and I'll get the info. Regards The Rebel

[lennyrebel]

First of all we would need to know if he has the updated HVAC system. So, are the HVAC controls the knobs or the "sliders". If he has the knobs it is the newer system, which I can help you with. The knob system is in fact vacuum controled, my guess would be the vacuum pump is not working any longer. Does he get defrost? If he gets defrost and nothing else (he may get some A/C from the vents) the pump itself is shot. Does he have access to a vacuum guage? If so tell him to pull the white line off of the wastegate solenoid, start the truck and measure for vacuum. He should get at least 18 hg in. If the pump is shot it will probably be more like 10.
Carey, I talked to my friend today and He does in fact have the knob system. He is going out to buy a vacuum gauge today. He says something about some air blowing out the defrost--cold air only. I'm trying to get him computer literate but so far no sucess. Thanks for your help. Regards The Rebel

[ssgharkness020147]

That sounds like a bad vacuum pump for sure. Only getting air out of the defrost is a tell tale sign. I have had two fail, both in the summer so I cannot say for sure that he would only get cold air. Seeing as how the temps contol is vacuum operated I would say that makes sense. On the other hand the blend door motor is electric. Have him pull the vacuum with a gauge and let me know how much he pulls.

[HUMMERDOGG.]

Carey Harkness
1997.5 Black Slantback
The Sole Remaining God Father

Carey-

Hey I just noticed in your footer... What happened? Did all the other Godfathers of Wheeling exit stage left leaving you holding the bag as the only one left??? What ever happened to H2R/Robert Rios or whatever his name is...

-Dogg

[ssgharkness020147]

Hey HUMMERDGG,
I dont know what happened to R2, he rode off into the sunset a long time ago. I heard a while ago that he sold his truck, not sure if thats true or not. As for the other Godfathers, who the hell knows. :confused:

Carey-

Hey I just noticed in your footer... What happened? Did all the other Godfathers of Wheeling exit stage left leaving you holding the bag as the only one left??? What ever happened to H2R/Robert Rios or whatever his name is...

-Dogg

[lennyrebel]

That sounds like a bad vacuum pump for sure. Only getting air out of the defrost is a tell tale sign. I have had two fail, both in the summer so I cannot say for sure that he would only get cold air. Seeing as how the temps contol is vacuum operated I would say that makes sense. On the other hand the blend door motor is electric. Have him pull the vacuum with a gauge and let me know how much he pulls.
Talked to my H1 friend today and He says he doesn't know where to look for vacuum pump. I see him at work and he doesn't bring the H1 there so I can't help Him look . If you could give me the location I'll point him in the right direction. Thanks, The Rebel

[ssgharkness020147]

It is below the atlenator. there will be a line running from the pump up to the wastegate solenoid, which is behind the altenator. Pull that line off and check it for vacuum.

[lennyrebel]

It is below the atlenator. there will be a line running from the pump up to the wastegate solenoid, which is behind the altenator. Pull that line off and check it for vacuum.
Roger That . I'll communicate to my friend and let you Know. Thanks, The Rebel

[lennyrebel]

That sounds like a bad vacuum pump for sure. Only getting air out of the defrost is a tell tale sign. I have had two fail, both in the summer so I cannot say for sure that he would only get cold air. Seeing as how the temps contol is vacuum operated I would say that makes sense. On the other hand the blend door motor is electric. Have him pull the vacuum with a gauge and let me know how much he pulls.
You were right Carey, it was a bad vacuum pump and my friend is replacing it today. Many thanks for your helpful knowledge and Merry Christmas to you. Regards The Rebel:)

[ssgharkness020147]

Glad to hear he got it figured out Reb. Make sure that he has the proper pully remover to get it off. Its just a standard power steering pully remover, any autoparts store has them. I hope for his sake the guy at the parts store told him that, I hate not being able to finish a job because of small crap like that.

Oh, and if he pulls the alternator it makes it a whole hell of alot easier to replace the pump. Just make sure to disconnect the batteries first, there is a hot wire on the alternator.