Matronics Email Lists Forum Index Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
 
 Get Email Distribution Too!Get Email Distribution Too!    FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Sniffle valve

 
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> Engines-List
View previous topic :: View next topic  
Author Message
Mark Phillips in TN



Joined: 10 Jan 2006
Posts: 431
Location: Columbia, TN

PostPosted: Mon May 21, 2007 3:04 pm    Post subject: Sniffle valve Reply with quote

I am installing a Lycoming sniffle valve (included in Vans FWF kit) to an Aerosport IO-360 and would like to confirm its inteded operation. I "think" it is basically a check valve that should open when manifold pressure is equal to atmospheric (engine not running) to drain any fuel pooled in the sump. Engine running, it should close when manifold pressure drops. The valve I have flows freely when blowing into the sump side, but still passes a bit of air when blown into from the tube side, which I surmise would constitute a small vacuum leak and possible leaner than normal operation.

Is this normal?

Thanks-
Mark

See what's free at AOL.com.
[quote][b]


- The Matronics Engines-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Engines-List

_________________
From The PossumWorks...
Back to top
View user's profile Send private message Send e-mail Visit poster's website
glcasey(at)adelphia.net
Guest





PostPosted: Tue May 22, 2007 4:15 am    Post subject: Sniffle valve Reply with quote

I assume most Lycoming installations (at least the 3 that I have
owned) just use a simple drain, so there is a "leak" the size of the
tube when the engine is running. The idle speed and mixture
adjustments compensate, so no one seems to worry. A sniffle valve
would presumably reduce that leak, but apparently isn't necessary.
Gary Casey

Quote:

I am installing a Lycoming sniffle valve (included in Vans FWF kit)
to an
Aerosport IO-360 and would like to confirm its inteded operation.
I "think" it

is basically a check valve that should open when manifold pressure
is equal to

atmospheric (engine not running) to drain any fuel pooled in the
sump. Engine

running, it should close when manifold pressure drops. The valve I
have
flows freely when blowing into the sump side, but still passes a
bit of air when

blown into from the tube side, which I surmise would constitute a
small vacuum

leak and possible leaner than normal operation.

Is this normal?

Thanks-
Mark


- The Matronics Engines-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Engines-List
Back to top
apilot2(at)gmail.com
Guest





PostPosted: Tue May 22, 2007 4:29 am    Post subject: Sniffle valve Reply with quote

The engines I'm familiar with all call for a sniffle valve, that looks
like a standard AN 90 degree fitting. I don't know how well it is
supposed to seal after fuel and gunk have drained through it for a few
years.

On 5/22/07, Gary Casey <glcasey(at)adelphia.net> wrote:
Quote:


I assume most Lycoming installations (at least the 3 that I have
owned) just use a simple drain, so there is a "leak" the size of the
tube when the engine is running. The idle speed and mixture
adjustments compensate, so no one seems to worry. A sniffle valve
would presumably reduce that leak, but apparently isn't necessary.
Gary Casey

>
> I am installing a Lycoming sniffle valve (included in Vans FWF kit)
> to an
> Aerosport IO-360 and would like to confirm its inteded operation.
> I "think" it
>
> is basically a check valve that should open when manifold pressure
> is equal to
>
> atmospheric (engine not running) to drain any fuel pooled in the
> sump. Engine
>
> running, it should close when manifold pressure drops. The valve I
> have
> flows freely when blowing into the sump side, but still passes a
> bit of air when
>
> blown into from the tube side, which I surmise would constitute a
> small vacuum
>
> leak and possible leaner than normal operation.
>
> Is this normal?
>
> Thanks-
> Mark


- The Matronics Engines-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Engines-List
Back to top
MONTY(at)bpaengines.com
Guest





PostPosted: Tue May 22, 2007 7:23 am    Post subject: Sniffle valve Reply with quote

If you have a small leak at the “ sniffle “ valve it will only effect you at idle and can be compensated with idle mixture adjustment. At WOT the engine doesn’t care as long as the leak is small. A big hole is another story.

Monty Barrett
BPE, Inc.

--


- The Matronics Engines-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Engines-List
Back to top
Mark Phillips in TN



Joined: 10 Jan 2006
Posts: 431
Location: Columbia, TN

PostPosted: Tue May 22, 2007 10:54 pm    Post subject: Sniffle valve Reply with quote

In a message dated 5/22/2007 10:25:10 AM Central Daylight Time,
MONTY(at)bpaengines.com writes:

If you have a small leak at the “ sniffle “ valve it will only effect you at
idle and can be compensated with idle mixture adjustment. At WOT the engine
doesn’t care as long as the leak is small. A big hole is another story.

Quote:
>>>

Thanks to all respondents- good discussion. Primary concern was a defective
part, but it don't sound like a biggie- I'm puttin' the sucker in since it's
paid for and shouldn't make the plane fall out of the sky! Cool

Mark do not archive

************************************** See what's free at http://www.aol.com


- The Matronics Engines-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Engines-List

_________________
From The PossumWorks...
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> Engines-List All times are GMT - 8 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Powered by phpBB © 2001, 2005 phpBB Group