Oil in Cabin

[Kerbs]

I have been flying the T-Craft quite a bit lately and noticed my right shoe is getting really dirty. After a little inspection, it looks like i am getting oil that is coming through the roughly 1" round vent (?) hole in the firewall. It's not a lot but enough that I don't want to fly in any nice pair of shoes and gets the carpet pretty gross. My oil consumption is about 1 qt every 10 hours. I'm not that concerned about the consumption but would prefer not to have oil splatter into the cabin. Is there any reason I should not plug that round hole in the firewall that comes into the cabin? I can try to get a picture in the next day or two.

[3Dreaming]

Re: Oil in Cabin

Absolutely that hole should be plugged, as well as any others through the firewall. Also check your oil pressure line to make sure there is not a small pin hole in it somewhere.

[Guest]

Re: Oil in Cabin

I have been flying the T-Craft quite a bit lately and noticed my right shoe is getting really dirty. After a little inspection, it looks like i am getting oil that is coming through the roughly 1" round vent (?) hole in the firewall. It's not a lot but enough that I don't want to fly in any nice pair of shoes and gets the carpet pretty gross. My oil consumption is about 1 qt every 10 hours. I'm not that concerned about the consumption but would prefer not to have oil splatter into the cabin. Is there any reason I should not plug that round hole in the firewall that comes into the cabin? I can try to get a picture in the next day or two.

Hi Stu,

They call it a "fire wall" for a reason.

There should be no holes and that should have been caught at the annual.

You can find sheet steel and round steel plugs to cover it up.

Dave R

[Hank Jarrett]

Re: Oil in Cabin

Picture a fire in the engine compartment. That hole would be a flame thrower. If it is a strange size for a stock plug you can cut a piece of sheet metal the size of the hole and thickness of the firewall with a second slightly larger piece on both sides. A 10-32 screw and nut to hold the stack together and fill the hole.

By the way, there shouldn't be oil mist in the engine compartment either. You need to clean the engine area up while you are plugging the hole and find the leak.

Hank

[Mark Bowden]

Re: Oil in Cabin

You might post a pic of how your breather tube is routed, some routings can "help" more oil escape. Air flow in the cowling can blow spray/drips in funny ways. Also there is a tube extension that can be added to the insert into the crankcase that can minimize crank splash from being forced out the breather tube should that be an issue in your situation.

For ref, max oil consumption per the Continental manuals is 3/4 pint per hour.

Mark

[Kerbs]

Re: Oil in Cabin

Thanks everyone. Makes sense and I will first get it plugged and everything cleaned up. I'll start seeing if I can figure out where the oil is coming from. I have an annual in a couple weeks and will also bring it up there. Thanks again for the help. Sometimes you just don't know what you don't know! Appreciate all the help.

[Kerbs]

Re: Oil in Cabin

I'll take a look at the breather and see if I can get a pict. Thanks Mark for the idea.

[M Towsley]

Re: Oil in Cabin

Do you have cabin heat and the corresponding outlet? Is that the hole you are speaking of?

[PA1195]

Re: Oil in Cabin

These can work but some like a screwed on metal patch: https://apexfasteners.com/fasteners/...s-plug-buttons Commonly found in the hardware section of most stores that sell things for home and cars.

[Kerbs]

Re: Oil in Cabin

Thanks Marty.

Ran out to the hanger this morning to take a look and see what I could do. Well I feel like a dumb-dumb because the hole I was referencing is indeed where the cabin heat comes in. Upon further inspection, I'm not positive that is where the oil is coming through. I did notice that some of the gaskets around the various cables passing through the firewall are pretty shot so I could be getting some there. I didn't have much time to tinker with it so I dig into it more this weekend.

Here's a picture just for reference. It looks like it's coming more from the right side, but that is the grommet that was in the worst shape.

[Kerbs]

Re: Oil in Cabin

Sorry, Not sure why the picture came through upside down.

[Hank Jarrett]

Re: Oil in Cabin

The picture came in up side down because that is how most of us have seen it! Standing on our heads under the panel and tank. ;-)

I think I would start by plugging up the heater outlet since I doubt you will need it much this time of year and see if the problem goes away. I would NOT delay fixing all the other firewall penetrations regardless and I would NOT put off fixing the the heater leak if that is what is doing it. If the oil IS coming from the heater muff that could mean a leak in the exhaust system which would be bad in two ways. First you would have exhaust coming into the cabin and second your valves would be blowing oil! Both are BAD!!! Problem is getting he heat muff off without taking he engine loose from the mount is almost impossible and you don't want to do it if you don't have to, but if you do suspect an exhaust leak, YOU HAVE TO!

Be safe and first step is to clean up the firewall and look for the source of the leak. When I started to get oil on my shoes it turned out to be a tiny leak at the oil pressure gauge that was running along different things under the cowl and finally dripping on my foot. The oil may NOT be coming from someplace obvious.

First priority is to be safe!

Hank

[3Dreaming]

Re: Oil in Cabin

Plugging up the holes is a good thing, but unless you have a major leak I doubt you oil is coming from the front side of the firewall. I would look real close at the oil pressure line and gauge. A very small leak there can make a big mess, because the oil is under pressure when the engine is running. I have seen this with other airplanes before.

[Mark Bowden]

Re: Oil in Cabin

Just an observation. The insulation/sound damping material on the firewall and floor board has been there a while, looks like linoleum (maybe cork). It also looks saturated with oil from a leak that has been there quite a while.

It is flowing down from the top of the picture. You might start with the oil pressure line as it penetrates the firewall, then up hill. Looks as though it is running down both on top of and behind the dampening.

It needs to be taken out of your cabin, take it out before you start chasing the leak. Other than the weight, smell and hazard, it can mask the leak source.

As you chase the leak by running/flying, don't forget to check the sump level before you go, don't fly it low/empty.

Mark

[Guest]

Re: Oil in Cabin

Fuel valve and/or fitting weeping and bleeding the asphalt out the sound dampener.

That's my thought.