Sniffle valve troubles

[Guest]

The other day we removed the sniffle valve(item 29) from an Ovation for cleaning in the ultrasonic bath after finding a sticky one in a Piper Seneca.  While working on it we found the connecting hose(item 24) rotten and failing.  The hoses is really meant for instrument air not engine compartments. The break was inside the fire sleeve.

Clarence

 

[Yetti]

think the factory did the non hydrocarbon hose?  

[kortopates]

Is that just a single sniffle valve at #30 with the hose before it? If so, I imagine that engine was running really rough. Interesting though, as I thought all the TSIO-360 installations had the sniffle valve where the aluminum tubing joins the 3 cyls on each side.

[Guest]

8 hours ago, kortopates said:

Is that just a single sniffle valve at #30 with the hose before it? If so, I imagine that engine was running really rough. Interesting though, as I thought all the TSIO-360 installations had the sniffle valve where the aluminum tubing joins the 3 cyls on each side.

Hi Paul,

#30 is the washer, #29 is the Parker 1H-19-15 valve, fastened to the right exhaust fairing.  The hose is the original, I’ve seen the same failure on an Acclaim.

It did start with an attempt to improve the ground idle mixture.

Clarence

[hypertech]

Did fixing the hose fix the ground idle roughness?

[kortopates]

5 hours ago, M20Doc said:

Hi Paul,

#30 is the washer, #29 is the Parker 1H-19-15 valve, fastened to the right exhaust fairing.  The hose is the original, I’ve seen the same failure on an Acclaim.

It did start with an attempt to improve the ground idle mixture.

Clarence

Thanks Clarence, after re-reading your post I realize now you were talking about an Ovation, but I misunderstood originally and thought this was a Seneca with a TSIO-360 with possibly a sniffle valve not up in the aluminium tubing. I understand you better now. I have also seen the aluminum tubing get chaffed through going to close to the engine where it comes down below it to the mate both sides just before the hose junction.

[Guest]

5 hours ago, hypertech said:

Did fixing the hose fix the ground idle roughness?

Yes, once replaced the idle was back to normal.

Clarence

[hypertech]

Thanks, I've been chasing a little bit of a rough idle since my overhaul.  That hose was replaced on mine with a new hose, which I think is a 124J hose.  I wonder if one of those fittings is loose or if my sniffle valve needs cleaning.  I'll have it checked at next month's annual.  I never would have thought that little hose could cause an idle issue.

[Guest]

12 hours ago, hypertech said:

Thanks, I've been chasing a little bit of a rough idle since my overhaul.  That hose was replaced on mine with a new hose, which I think is a 124J hose.  I wonder if one of those fittings is loose or if my sniffle valve needs cleaning.  I'll have it checked at next month's annual.  I never would have thought that little hose could cause an idle issue.

A leaking sniffle valve or broken hose can leak a lot of air, your 550 is quite a vacuum source at idle.

Clarence

[FlyWalt]

Amazingly enough, the guy that reinstalled my engine after the overhaul never reinstalled the sniffle valve. But I sure was sniffing when I saw the bill for a new one to be installed by the MSC that discovered it.

[carusoam]

Thanks for the heads up Clarence!

Somebody has selected various hoses that were not very good for their intended purposes some days...

• PVC tubing for the vacuum pump in the tail... (bleeds the lubricant from the polymer into the vac system...)
• Instrument air hose for the sniffle valve... (its a fuel drain... the hose dissolves when it comes in contact with an organic solvent, aka fuel...)

Some things to check for at annual... or if you have a rough idle.

If not familiar with the sniffle valve... Fuel injection systems have a drain for excess fuel that occurs either from start-up or shut down... the one way valve allows the excess fuel to escape....  if the valve stops functioning, or the hose falls off... unmetered air enters into the intake system causing challenges that show up the most at idle...

PP thoughts only, not a mechanic...

Best regards,

-a-

[Guest]

2 hours ago, carusoam said:

Thanks for the heads up Clarence!

Somebody has selected various hoses that were not very good for their intended purposes some days...

• PVC tubing for the vacuum pump in the tail... (bleeds the lubricant from the polymer into the vac system...)
• Instrument air hose for the sniffle valve... (its a fuel drain... the hose dissolves when it comes in contact with an organic solvent, aka fuel...)

Some things to check for at annual... or if you have a rough idle.

If not familiar with the sniffle valve... Fuel injection systems have a drain for excess fuel that occurs either from start-up or shut down... the one way valve allows the excess fuel to escape....  if the valve stops functioning, or the hose falls off... unmetered air enters into the intake system causing challenges that show up the most at idle...

PP thoughts only, not a mechanic...

Best regards,

-a-

Anthony,

Here is a picture of the sniffle valve, 1H19-5.  It’s installed in the left exhaust fairing of the Ovation, secured with a 13/16” nut.  On the K models it’s secured with an Adel clamp in the left exhaust fairing.

Clarence

Edited February 5, 2019 by M20Doc

[Will.iam]

This was the only topic i found on mooneyspace about sniffle valves but my question was not asked so here it goes. I was doing a piston ring flush on the cylinders and started with #2 cylinder on a tsio-360 mb2 engine. That cylinder was fine when i poured the solution into the cylinder and hydrolocked it the fluid flowed down into the oil pan and out the drain hole. When i went to do cylinder #4 as i was filling up the cylinder the solution started running out the sniffle overflow tube like when you prime the engine too much with gas. At first i thought i had the piston somewhere wrong in the cycle but confirmed 3 times that it was on the compression stroke. Even brought the piston to TDC and added some fluid only to have it start leaking out the sniffle tube. I went ahead to cylinder #6 and tried that cylinder and it worked just like #2 did and left it compressed overnight for a good soaking. Will do cylinders #5, #3, #1 tomorrow to see if any of those drain to the sniffle tube if not any ideas why the #4 cylinder does? Ironically I couldn’t get the idle lean enough for 50 RPM rise at cutoff. It was going up to 200rpm rise with the idle screw all the way lean. That’s when the A&P sent the throttle body, spider, and fuel pump to be repaired as i also had a rough idle. Now with this thread talking about rough idling i wonder if we barked up the wrong tree, except y’all talk about the mixture going lean and mine went rich. 
At first i thought maybe my exhaust valve or intake valve was not seating and the solution was flowing around the valve but when i turn the prop on compression stroke pressure builds up on my finger and stays for over 30 seconds so air is not leaving quickly. Also if i quickly add fluid and put the plug back in and turn the prop fluid also goes out the drain in the oil pan but also out the sniffle tube as well although not as fast.

any ideas why this is happening on cylinder #4 would be great  

 

[carusoam]

17 minutes ago, Will.iam said:

This was the only topic i found on mooneyspace about sniffle valves

 

Really?

 

A few pages of “sniffle valve” search….

-a-

https://mooneyspace.com/search/?q="Sniffle valve"&quick=1&updated_after=any&sortby=relevancy

[carusoam]

Be familiar with how the sniffle valve drain is plumbed for your plane…

It essentially is an intake drain….

When too much fuel is dumped in the intake, gravity sends it towards the sniffle valve drain… 

When the engine starts the engine vacuum pulls the ball valve closed…

 

Sounds like your intake valve is open while the cleaning fluid is in the cylinder… allowing passage towards the intake system…?

For more specific searches use Google…. And your model of plane…. The sniffle valve and its plumbing may be very engine specific…

PP guesses only, good luck with the hunt…

Best regards,

-a-

[Will.iam]

1 hour ago, carusoam said:

Really?

 

A few pages of “sniffle valve” search….

-a-

https://mooneyspace.com/search/?q="Sniffle valve"&quick=1&updated_after=any&sortby=relevancy

Sorry -a- i used google fu which normally returns more accurate data than mooneyspace seach but not so this time. Thanks for the additional linked subjects. 
 

p. S. I was lazy and searched mooneyspace sniff instead of sniffle and that does make a difference 

 

[carusoam]

12 hours ago, Will.iam said:

Sorry -a- i used google fu which normally returns more accurate data than mooneyspace seach but not so this time. Thanks for the additional linked subjects. 
 

p. S. I was lazy and searched mooneyspace sniff instead of sniffle and that does make a difference 

 

There seams to be something unique about the word sniffle…

the search does pretty good with four letters or more….

just not this time…

searching for both words together made the difference…

-a-

[Will.iam]

Well finishing the flush on cylinders 1, 3, and 5. #3 the mid cylinder like #4 was the mid cylinder also started flowing out the sniffle tube but only when compressing the solution not like #4 that started pouring out the sniffle the moment you start adding into the cylinder. Waiting for my new va-400 scope to come in so i can more closely inspect the intake valve especially on #3 as it would act that way if the valve was not fully sealing against the seat and solution was being pushed past it as well as the rings. At least it’s symmetrical happening to the middle cylinders.