Schrader Valve question

MuseChaser

MuseChaser

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MuseChaser
Dumb question #34b...

Is the Schrader valve core in an AN812-1 strut valve different than the core you'd get from any regular store?
 
Unit74 said:
Yes... it will Be more expensive..

Honestly, I don’t know but I had to say something snarky. That’s what I do.....
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Lol... I hear the aviation aisle at Home Depot has them for less...

In all seriousness, the valve is described as a high pressure valve rated up to 1500 psi, and I suspect the trashed core I removed may have been ...ummmm... not up to the task....
 
MuseChaser said:
Lol... I hear the aviation aisle at Home Depot has them for less...

In all seriousness, the valve is described as a high pressure valve rated up to 1500 psi, and I suspect the trashed core I removed may have been ...ummmm... not up to the task....
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Ehhgem...you mean those owner manufactured parts? I’d get rid of those before the guy with the name tag on and clip board shows up.
 
Last edited:
Timbeck2 said:
Yes it is different. The ones for cars are rated to a hundreds pounds or so. The valve in the strut is rated to a lot more, I want to say around 2500 psi. edit: or up to 4000 psi.

At about $3 apiece and you only need two, it isn't a major issue.

https://www.aircraftspruce.com/catalog/lgpages/9914B.php?clickkey=8151
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Thanks, Timbeck.. The AN812-1 valve specified in the parts list for my plane is rated to 1500 psi, and the valve core is AN809-1. The only AN812-1 I could find was also listed here - https://www.skygeek.com/dill-controls-sk15171-302-637-strut-valve.html - as SK15171, and it comes with a 302-DN core. Searches for "AN809-1" list 302DN as an alternate #, and they're rated from 0-2000psi. The core to which you linked lists an operating pressure from 200-4000 psi; is it possible the low end of 200 psi is too high for the little Cherokee 140 front strut when unloaded, or doesn't that matter?

And... Skygeek has the 302DN cores for 95 cents (plus $15 shipping!?!!?!?), while Aircraftsupply.com sells them for $3.95. In the grand scheme of AviationMonetaryUnits, it ain't a thang.. but still.... why?!? Couldn't find anything for AN812-1, SK15171, or 302DN (and various usual permutations omitting/inserting dashes, spaces, etc) on Aircraft Spruce, which is a shame because I've had good experiences with them throughout the years.

I'm guessing my years-long struggles with a slowly collapsing front strut may all be due to a PO or someone else using a standard tire-pressure-rated valve core. Sigh. Sure wish I had checked this out years ago.
 
MuseChaser said:
. The core to which you linked lists an operating pressure from 200-4000 psi; is it possible the low end of 200 psi is too high for the little Cherokee 140 front strut when unloaded, or doesn't that matter?
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The presssure in there can get a lot higher when someone plants the nosewheel hard on the runway.
 
MuseChaser said:
...is it possible the low end of 200 psi is too high for the little Cherokee 140 front strut when unloaded, or doesn't that matter?..
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Your front strut, actually all your struts for that matter will take whatever psi that is required to maintain the distance necessary depicted in the maintenance manual. Off the top of my head the mains are 4.25", a little less for the nose. Usually about 500 psi is used as a starting point and then pressure is bled off to get the required distance. So no, it isn't too high and it will probably be over 200 psi when you're finished.
 
Thanks, all. Much appreciated.
 
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