SR22 Oil Drain Tube

I am a new owner of a 2004 SR22 with 30hr complete overhaul there is three tubes under the airplane the one small one on the left sitting in the pilots seat has a check valve on it, the question is while test running after oil change oil came out probably an 1/2 ounce or so, on a recent 5 hour trip i used about 1 quart of oil ! Just wondering what the oil lines and check valve do on this engine ?


Not sure without a Pic, but if I understand you correctly, the ‘check valve’ is a Fuel Sump outlet, to dump fuel in your gascolator.

The pin in your sump cup will open up the valve.

Needed to add: You should be dumping that in your preflites. Altho I don’t feel that one is as important as the four tank sump outlets, it is still there and should be sumped before each flight.

Sumping, not dumping… Arrrggh sometimes I dispise autospell.

Yours should look like this. The ports are the following:

On the pilots side port is a sniffle valve. It’s purpose is to allow fuel that is in the fuel drain tubes (from priming the engine) to flow out overboard when the engine is not running. When the engine is running it needs to close to avoid it being it be a huge vacuum leak. The system looks like this.

Red are the fuel drains, one at each cylinder. The blue circle is what I think you’re asking about, the sniffle valve. There is no oil line down there. There is a crankcase breather tube (the large diameter tube) that minor amounts of oil will come out along with the blowby that comes out in normal operation.

Thank You you answered my question perfectly !!

As far as your oil usage question, there are many threads on this. If the engine has sat idle for a few days, all the oil in the filter and clinging to the inside of the engine will drain to the sump. This can be up to a quart, so it is important when you measure your oil level to really see how much you are using. Also, while the sump is 8 quarts, most engines will just blow out the eighth quart. Each engine seems to have it’s happy place somewhere between 6-7 quarts of oil. I only put seven at oil changes.

You can also do a search for the Garfinkle extension for your oil breather tube…many have had success with this.

Thanks for the response I installed an Air Wolf Air/Oil Separator and that fixed the oil on the belly, but I thought that the small tube could have something to do with oil usage but as I have learned it does not ! I let the engine set for a week before i decided that it used a quart oil oil ! I did add 8 quarts of oil at oil change time and with the larger oil filter it only showed 7 quarts after an 30 min test flight !

Have you calibrated your dipstick? If I put 8 quarts in mine only reads 6 1/2 or thereabouts.

via COPAme

Hi Roger. After a couple hour flight I notice literally one or two drops of what appear to be oil out of my copilot side fuel drain port. Any ideas what this could be. Being trace in nature, could it be normal?


Not Roger however I’m awake.

The right port is the cavity drain for the electric driven and engine driven fuel pump and the fuel flow divider. There is a “T” connection to combine the appropriate hoses just above the exit point.

Oil is a warning.

Find the source.

It appears both Jim and I are on line at the same time. Our advice is essentially the same.

Being pragmatic, it seems the engine driven fuel pump could be the source; however, there’s no potential for the electric fuel pump to emit oil. Would you agree with that?

The engine seems to be most likely.

Exercise skills of maintenance trouble shooting before condemning the EDP.

Access the T and confirm the drain hose to each component. Separate and note the source line of the oil… one might be surprised that the electric pump has a lubricant when mixed with fuel resembles engine oil…


Easy for you to say! [;)]

Your description of fuel lubricant mixture looking like oil (dark blue) would describe what I have been seeing lately under cowling of 2009 TN. It is in for annual now Any recommendations?


This doesn’t answer your question directly, but dark blue is from evaporated fuel – the faint blue dye stays around when the fuel evaporates. So if you’re seeing that, there is fuel involved.

Jim, does yours look like this image?

After reading this thread I looked to see what mine was looking like. This is after not cleaning the belly for probably 15-20 hours of flying. How much is normal? I just cleaned the belly near this port and I’m going to watch the accumulation.

That is a troubling Signature to me. The fuel stain strongly suggests the co pilot side is leaking. That concerns me more than the liquid fuel on the pilot side. Any fuel leak on the co pilot side is from fuel leaking from inside one of the fuel pumps or the spider valve. None of those are good. Pull the drain hoses off and work backwards to the source. I would look at the electric pump first.

The liquid fuel could be just a small amount of overpriming that released once the sniffle valve opened.

If would like a longer explanation call me. Glad to talk.