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Sniffle valve line

wirejock

Well Known Member
IO-360-M1B
I searched but only found questions about the valve.
I have a Airflow Performance Sniffle Valve installed.

Questions
What sort of hose should be connected? It's an AN816
Where should it come out of the fuse?

I'm thinking a section of aluminum tube transitioning to plastic then back to aluminum to exit.
Photos?
 
Use a piece of 3/8" rubber hose (fuel injection line, MIL-DTL-6000D, power steering, etc.) to transition from the sniffle valve to a length of 3/8" aluminum tube. Position the end of the tube between the exhaust pipes, secure to fuselage/firewall with rubber cushion clamp as depicted in OP-32

See OP-32 excerpts for Nose and Taildragger options (attached)
 

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I used a spark plug boot. It fit perfectly.
 

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OP-32

Use a piece of 3/8" rubber hose (fuel injection line, MIL-DTL-6000D, power steering, etc.) to transition from the sniffle valve to a length of 3/8" aluminum tube. Position the end of the tube between the exhaust pipes, secure to fuselage/firewall with rubber cushion clamp as depicted in OP-32

See OP-32 excerpts for Nose and Taildragger options (attached)

Thanks Brian
I'll check OP-32 tomorrow.
Guess I better review them all again. Missed that.
 
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I had cowl and exhaust clearance issues with my sniffle valve drain line, with a Superior cold air sump and cross-over exhaust. Once I got those issues handled the line rubbed on the smooth lower cowl (non-scoop).
I ended up going with the shorter Airflow Performance Manifold Drain instead of the sniffle valve, which allowed more room for manipulating the drain line. https://airflowperformance.com/index.php/product/manifold-drain/
 
I think I'm having the same issues with my IO-375. Superior Cold Air Sump and a Vetterman cross over exhaust. It's VERY tight there. I've sent an email request to AirFlowPerformance, but maybe you can answer. Is that shorter manifold fitting they sell equipped with the same thermal valve that closes when hot and opens when cold? It's a fraction of the cost of the Lycoming Sniffle Valve.
 
Just a little ball?

In both the $160 Lycoming "Sniffle Valve" and the $38 Airflow Performance Manifold Drain? Functionally they're equal?
 
I've not looked inside the Lycoming part. For $160 I never will ;)

Functionally they do the same thing.
 
I'm thinking a section of aluminum tube transitioning to plastic then back to aluminum to exit.
Photos?

Bingo, exactly what I did. Have had zero issues. This middle section is rubber fuel line.

Sorry pics aren't great. I drilled a small hole in the firewall flange, that is where it exits.
 

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Equivalent in operation, vastly different in cost.

I am informed now. The two valves, Lycoming "Sniffle Valve" and the Airflow Performance valve do the same thing, but in different ways. The Lycoming ($160) operates via engine heat which closes the valve when operating and opens the drain valve when the engine cools. The Airflow Manifold Drain ($38) operates by the vacuum in the intake manifold which pulls the valve closed if a vacuum is present and opens the valve once the vacuum ceases.

Got it.
 
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