Climate Control/Vacuum Woes
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From: Buffalo
Climate Control/Vacuum Woes
Has anyone ever delved into diagnosing this system?
Currently I'm getting no vacuum to my recirc vacuum motor. So far I've made sure that source vacuum is present at the selector switch, verified the check valve under the hood is good, and replaced the selector switch with a "known good" switch and it has solved nothing. I've disconnected the vacuum connector under the glovebox which goes out into the engine compartment and made a "jumper" to still apply source vacuum to switch while leaving the recirc line open to test for vacuum.
The only other fault in the system is when the selector switch is in DEFROST, on top of getting air out of the defroster nozzles, I also get it coming out of the floor vents. Other than that, the system is working properly.
So I know lines can get kinked or clogged, but I've pretty much tested for vacuum right off the selector switch and am getting nothing.
What the heck could be causing this?
'84 F250 with integral AC by the way.
Currently I'm getting no vacuum to my recirc vacuum motor. So far I've made sure that source vacuum is present at the selector switch, verified the check valve under the hood is good, and replaced the selector switch with a "known good" switch and it has solved nothing. I've disconnected the vacuum connector under the glovebox which goes out into the engine compartment and made a "jumper" to still apply source vacuum to switch while leaving the recirc line open to test for vacuum.
The only other fault in the system is when the selector switch is in DEFROST, on top of getting air out of the defroster nozzles, I also get it coming out of the floor vents. Other than that, the system is working properly.
So I know lines can get kinked or clogged, but I've pretty much tested for vacuum right off the selector switch and am getting nothing.
What the heck could be causing this?
'84 F250 with integral AC by the way.
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From: AZ
Have you checked the vacuum at the diverter under the hood by the passenger side fender on the firewall? That is the actual diverter for the recirc and fresh air. See if you have vacuum at that point first. If yes, then the diverter may have a leak inside.
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From: Buffalo
I'll apply vacuum to it to see if it holds, but I thought that was just a storage tank for the source.
If you are talking about the 3 port check valve, then yes, I have checked that and it does hold vacuum. There are only two lines entering through the firewall into the cabin, source and recirc.
It's like I'm getting nothing out of the switch to supply the recirc motor.
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From: AZ
No, yours may be different than 1983. On the air box you will see a silver diverter that is attached to the door arm that changes the air intake. You should see a vacuum line going to it from the tree located on the firewall that is held in place with two screws. The black ball is just a reserve for vacuum.
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From: Buffalo
No, yours may be different than 1983. On the air box you will see a silver diverter that is attached to the door arm that changes the air intake. You should see a vacuum line going to it from the tree located on the firewall that is held in place with two screws. The black ball is just a reserve for vacuum.
Oh, the actual vacuum motor itself. Yes, I did check that first and it is bad. I ordered a new one, but I haven't installed it yet because when I checked the motor, I also checked for vacuum at the motor and did not have any.
What I'm trying to figure out is why I'm getting no vacuum to the recirc door motor.
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