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Sniffle valve on Exp 119

Ron B.

Well Known Member
The location I we have chosen for the Sniffle valve has it very close to the exhaust pipe. The bottom of this engine is different from what is in the photo in the EXP 119 KAI manual. We chose the centre of the three holes, if we were to move over to the right hole we would have approximately 1/2” clearance. Don’t know what moving over would do to the function of the valve?
 
The sniffle valve contains a metal ball that closes the valve when the intake plenum is at a lower pressure than atmospheric (e.g. vacuum)

When the engine is not running the ball falls, allowing the contents of the cylinders, intake runners, etc. (usually some fuel & oil) to dribble out and make a mess on the hangar floor.

Some operators eliminate the valve entirely and don't seem to experience any negative effects...

See thread - https://vansairforce.net/community/showthread.php?t=198643&highlight=sniffle

Great pictures.
 
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The location I we have chosen for the Sniffle valve has it very close to the exhaust pipe. The bottom of this engine is different from what is in the photo in the EXP 119 KAI manual. We chose the centre of the three holes, if we were to move over to the right hole we would have approximately 1/2” clearance. Don’t know what moving over would do to the function of the valve?

It will not do anything in the function of the valve and I installed it in the middle hole. In my opinion, there is enough clearance in that location. What I have not liked about VAN's plans is the hose and how it exits the cowl so I have made a small modification to that for support and exiting but I am not flying yet and only time will tell.
 
Some operators eliminate the valve entirely and don't seem to experience any negative effects...

True for the "big box" horizontal intake sump on earlier 390 A's and EXP's, as it has a lot of internal volume. The intake manifold volume on the C/D/119's "cold air" package is far smaller. I'd strongly recommend using a sniffle on the 119.
 
Called Van's tech. support about the interference and they were not concerned. Leaving it with about 1?8" clearance and will keep an eye on it.
 
As for the sniffle valve, I’d be more worried about it allowing water in the intake from sitting outside draining than a little oil. Would not skip it. I made a small heat shield that clamps to the exhaust in that area. The rubber drain hose bends around that and has held up very well.
 
As for the sniffle valve, I’d be more worried about it allowing water in the intake from sitting outside draining than a little oil. Would not skip it. I made a small heat shield that clamps to the exhaust in that area. The rubber drain hose bends around that and has held up very well.
A small hole at the bottom of your snorkel, unless you don't have a snorkel is a good way of preventing water getting into your intake.
 
I have seen sniffle valves open and close at idle power, causing a "surge" while taxi; If you do not over prime, you don't need one!! Also, on some sumps on tail draggers, you would have to reallllly over prime a bunch to allow the sniffle valve to do its job!

DAR Gary
 
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