Vacuum sucks. Low pressure?

alaskan9974

alaskan9974

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alaskan9974
I have a wet vac pump with about 200 hours on it driving a AI and wing leveler. Noticing less pressure, 4” vs it’s usual 5”, no change over 50 hours.

Pressure doesn’t fluctuate, my IA adjusted the regulator but there was no change up, would a bad regulator cause that?
 
Last edited:
alaskan9974 said:
I have a wet vac pump with about 200 hours on it driving a AI and wing leveler. Noticing less pressure, 4” vs it’s usual 5”, no change over 50 hours.

Pressure doesn’t fluctuate, my IA adjusted the regulator but there was no change up, would a bad regulator cause that?
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Regulators can stick. I found one that had corrosion on its valve face. But most low pressure problems are either a bad pump or a leaking line or fitting somewhere, which is what I'd look for first. I once found an aluminum vacuum line with a huge hole in it caused by corrosion. Some older airplanes had sections of line like that instead of the all-hose most have now.

A really dirty central vacuum filter will also drop the vacuum differential, which is what most gauges are plumbed for. And the vacuum relief filter, usually a foam garter on the regulator valve, might be shot, too, and bits of it have gotten into the valve and are holding it open. Both filters are supposed to be checked at annual, but I often found them totally shot, especially that foam filter. Often came off as dust, they were that old. And that dust and stuff goes right into the pump, too.

Maintenance. It always comes down to maintenance.
 
Wing leveler has a leak.
 
Tom-D said:
Wing leveler has a leak.
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Wouldn't the pressure drop or change when its turned on?

Replacing all the hoses tomorrow, they are about 10 years old. Ordered a new regulator. This one looks simple to clean but they were surprisingly cheap.
 
Where are the regulator valve and filter typically located?

What about on a 182P?
 
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