Induction Drain Valve drip

[PTK]

Is it normal for the line from the induction drain valve to drip a little after engine shutdown?

I'm referring to the smaller tube under pilot's side next to breather tube.

I noticed it was dripping a very small amount today on shutdown after a long flight. More like a "weeping" which caused a few drops to accumulate on the tarmac during the few minutes time it took us to deplane.

[co2bruce]

Ours does a little

[Bob_Belville]

Yes.

[PTK]

Thank you all!

I hadn't really noticed it before. I caught a drop between my index finger and thumb to feel and smell it.

I can't say it was fuel really. It felt more like the consistency of water.

[rgpilot]

When I flew a m20J it did the same thing.

[carusoam]

Can anyone explain the sniffle valve operation? (If that's the one...)

When does it fill up? Excess priming?

When does it empty? Excess fuel floats the ball?

How does it stay closed? Gravity?

If it leaks after the flight, how did excess fuel stay in there or get in there?

These are ideas that come to mind...

It sounds to me like there shouldn't be fuel leaking after the flight if the valve is operating properly. Getting it cleaned may be all it takes.

Let me know if I missed the boat...

I don't mean to derail the original request.

Best regards,

-a-

[N601RX]

With engine off ball falls to bottom which is on and allows any fuel to drain. With engine running the light ball is sucked upward and closes off.

[Piloto]

The dripping is normal. It comes from the fuel injectors discharging the excess fuel into the air plenum inside the oil sump. It will also show when you prime the engine with the electric pump.

 

José

[CoachTom]

One way to clean the line as the "drains" are located directly under the injectors, is to go full rich/ full throttle and turn max boost pump on until the fuel comes out: then shut off boost pump.

The fuel will pool/overflow the intake plenum where those drains are installed and ball bearing and assembly is cleaned by the 100ll cleaning solution.  This is functioning as designed.