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Old Oct 19, 2009 | 05:54 PM
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4x4 vacuum question

well i havent been on here in a while but ... anyways i just installed warn manual locking hubs because my 4x4 wouldent work . now i turn on my 4x4 and i still loose my hvac system i did plug the lines that use to go to the old auto hubs heres my question where do those lines get vacuum from so i can plug it right from the source pictures would be awesome thanks
 
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Old Oct 19, 2009 | 06:06 PM
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Look above the right front fender well for the balck coffee can looking thing. That is the vaccum canister. One line will track to a solenoid valve bolted to the fender well. Plug that line before the valve and you will have isolated the 4x4 aspects of the system.
 
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Old Oct 20, 2009 | 10:48 AM
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You don't have to plug the vacuum line. Just unplug the connection on the solenoid for the front hubs that sits on the passenger firewall. The solenoid will not send vacuum to the hubs with this unpluged Here is a pic of it unpluged.



 
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Old Oct 20, 2009 | 11:06 AM
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Pic of vacuum system from Passenger side.

 
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Old Oct 20, 2009 | 11:57 AM
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Also, be SURE to plug off the vacuum ports down on the hubs, as you will allow dirt and water into them otherwise.

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Old Oct 20, 2009 | 12:51 PM
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Originally Posted by miller_feed
You don't have to plug the vacuum line. Just unplug the connection on the solenoid for the front hubs that sits on the passenger firewall. The solenoid will not send vacuum to the hubs with this unpluged Here is a pic of it unpluged.



I agree with miller_feed. If you already disconnected the hubs and plugged the lines and you are still having vacuum problems when you click in or out of 4x4 (defrost on the ventilation), then all I can think of is poor line plugging, crack/split in the line or a bad solenoid. If you disconnect the line going TO the solenoid from the vacuum system (should come from either the pump or the reservoir), then you've isolated the whole hub locking portion from the system.
 
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Old Oct 20, 2009 | 01:40 PM
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Of course if the solenoid is failed open, like mine was, you will need to plug the line goint to it...
 
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Old Oct 20, 2009 | 01:48 PM
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Originally Posted by MR5x5
Of course if the solenoid is failed open, like mine was, you will need to plug the line goint to it...
I agree with this. I was thinking of a working solenoid.
 
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