Just in case you are curious Vapor 2 way valve

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76was124
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Re: Just in case you are curious Vapor 2 way valve

Postby 76was124 » Tue Jul 04, 2017 7:36 am

My rudimentary testing a few years back indicated that a properly functioning 2 way valve has two different 'open' thresholds depending on pressure or vacuum. Not sure if that's splitting hairs or not, but something I observed.
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RRoller123
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Re: Just in case you are curious Vapor 2 way valve

Postby RRoller123 » Wed Jul 05, 2017 6:58 am

Exactly, there is a higher pressure (or vacuum) setting in one direction versus the other. This was done for a purpose, and the fuel filter won't perform the same function.

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'80 FI Spider 2000
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'75 BMW R75/6
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joelittel
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Re: Just in case you are curious Vapor 2 way valve

Postby joelittel » Wed Jul 05, 2017 11:04 am

Should I be looking into a new charcoal canister to go with my new valve?

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RRoller123
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Re: Just in case you are curious Vapor 2 way valve

Postby RRoller123 » Wed Jul 05, 2017 11:24 am

I can't answer as to whether it still works (charcoal) but you can check and see if it is plugged up? :?: It should allow some air flow with reasonably small pressure through the various orifices.

p.s. The 2-way valve operates in a step function; i.e. there is no air flow until a set pressure is reached, then it opens and allows flow. Also, the step is different in each direction.
'80 FI Spider 2000
'74 and '79 X1/9 (past)
'75 BMW R75/6
2011 Chevy Malibu (daily driver)
2010 Chevy Silverado 2500HD Ext Cab 4WD/STD BED
2002 Edgewater 175CC 80HP 4-Stroke Yamaha
2003 Jaguar XK8
2003 Jaguar XKR
2021 Jayco 22RB
2019 Bianchi Torino Bicycle

76was124
Patron 2019
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Posts: 620
Joined: Sun May 16, 2010 4:43 pm
Your car is a: 1981 Spider 2000
Location: Detroit Area

Re: Just in case you are curious Vapor 2 way valve

Postby 76was124 » Wed Aug 09, 2017 7:56 pm

There is a metered orfice in the vent cap on the charcoal canister. Plugging it can cause a stall, or not having the cap does impact idle speed.
Last edited by 76was124 on Sat Aug 12, 2017 7:55 am, edited 1 time in total.
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PhillySpider
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Re: Just in case you are curious Vapor 2 way valve

Postby PhillySpider » Fri Aug 11, 2017 10:51 am

Bought a NOS valve in the sealed FIAT baggy for $14 off the bay. Very happy, kept the old one as a back up. Don't want a lawn mower fuel filter on our Bella,...trying to go for the original survivor thing...


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