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Getting Vacuum to test box ??

dspur

dspur

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My heat a/c box was rebuilt some time back. Also my vacuum switch was rebuilt. I am trying to test before installing.
All of the vacuum lines are connected to the actuators etc. If I put my thumb over the inlet that plugs into the vac switch, I get vacuum (see pic).
If I hook to the vacuum switch I get no vacuum regardless of which button is pushed in. This is the original switch rebuilt by Mr Powell almost two years ago.
I had a spare, tho different number and I tried that one with same result.

My thinking was to hook vacuum to test the box actuators in each position.

Maybe this doesn’t work because? What am I doing wrong? Possible both switches are bad or am I leaving out a step? Any other way to test the actuators and re-test the switch? I don’t want to install and then have to take it back out for some reason.

I am not very well versed in these systems

TIA

IMG_2796.jpeg


IMG_2797.jpeg
 
The switch is probably leaking. Looking at the big melt in it I’m guessing the plates inside the switch aren’t shifting and moving as they should.

There are after repop ones available and NOS ones still kicking around north on the internet
 
Last edited:
4mulas said:
The switch is probably leaking. Looking at the big melt in it I’m guessing the plates inside the switch are shifting and moving as they should.

There are after repop ones available and NOS ones still kicking around north on the internet
Click to expand...
Thanks. I paid to have this one rebuilt, but if this is the problem I will replace. So I should have vacuum with a (good) switch attached?
 
dspur said:
Thanks. I paid to have this one rebuilt, but if this is the problem I will replace. So I should have vacuum with a (good) switch attached?
Click to expand...
Who rebuilt it ? I had a member here rebuild mine.
 
Yes you would still vacuum, but if it's being applied to the wrong port it won't do anything...
 
I had issues checking mine with a vacuum pump but it worked fine when hooked up. I concluded that my pump could not constsntly supply the volume of vacuum needed to make the actuators work properly. Putting your thumb over the plug is really only checking the input line and nothing else.
 
dspur said:
Anthony Powell. About 2 1/2 years ago. Been sitting ever since so that might be the problem, I dunno
Click to expand...
It should still be good,did you contact him about it?
 
Did you get it figured out?
 
davek said:
Did you get it figured out?
Click to expand...
Not yet. Did a little checking and testing the actuators. Concerned one may not be working properly so that may be it but not sure yet. Also need to make sure I have all hooked up properly etc. Hope to be working on it some more this week.
 
You won't build enough vacuum with a hand pump to test your system that way. you will need to have a small electric vacuum pump or some other constant source of vacuum.
 
Kilrbee said:
You won't build enough vacuum with a hand pump to test your system that way. you will need to have a small electric vacuum pump or some other constant source of vacuum.
Click to expand...
Yes I’ve figured that out. Looking for something now. Thank you.
 
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