Oil on left nose gear door

[Bigdaddie]

I just did my first oil change myself on my 231.  I ran the airplane pretty hard and checked for leaks and found none.  After I flew it there was oil on the outside of the left nose gear door.  A single paper towel cleaned it up.

I added 8qts of oil plus 16oz of Cam Guard.

Do you think it is just blowing the oil out the breather due to being over filled or spilled oil I didn't catch and clean up?  It seems to me that breather oil would be aft of the cowling. I can't find any leaks in the engine compartment.

[Ragsf15e]

3 minutes ago, Bigdaddie said:

I just did my first oil change myself on my 231.  I ran the airplane pretty hard and checked for leaks and found none.  After I flew it there was oil on the outside of the left nose gear door.  A single paper towel cleaned it up.

I added 8qts of oil plus 16oz of Cam Guard.

Do you think it is just blowing the oil out the breather due to being over filled or spilled oil I didn't catch and clean up?  It seems to me that breather oil would be aft of the cowling. I can't find any leaks in the engine compartment.

I would say both.  It’s impossible to not spill a few drips.  A little looks like a lot.  Are there any drops on the drain?  Mine spits some out the breather anyway.  Also, why did you do 8qts?  Typically they spit extra out the breather if you top it off.  I usually put in 7 (some fills the filter) and then keep the level ~6. It blows out less.  Is yours different? (Mine is an SB engine but should be similar)

[Bigdaddie]

25 minutes ago, Ragsf15e said:

I would say both.  It’s impossible to not spill a few drips.  A little looks like a lot.  Are there any drops on the drain?  Mine spits some out the breather anyway.  Also, why did you do 8qts?  Typically they spit extra out the breather if you top it off.  I usually put in 7 (some fills the filter) and then keep the level ~6. It blows out less.  Is yours different? (Mine is an SB engine but should be similar)

I added 8qts because I'm a dumb dumb.  I know that it takes a few days of the aircraft sitting before you get an accurate dipstick reading.  Just something about seeing only 6qts on the dipstick made me add the extra qt.  I usually run at 7qts and add a qt when it reads 6.  With that I don't notice much blow by or oil consumption (maybe a qt every 12hrs or so).  And yes there is a drip or two coming out of the breather.  I just wonder how it gets from the breather to the gear door as it looks like it would have to travel upwind.  Mine is a LB engine. 

[47U]

33 minutes ago, Bigdaddie said:

I just did my first oil change myself on my 231.

First oil change… so the airplane is new to you?  As @Ragsf15e says, probably spit out the breather.  

If you have an 8 qt sump, and you put in 8 qts plus 16 oz CamGuard, then you were definitely overfilled.  The CamGuard ratio is 1.6 oz per quart of oil, so following Rags15e procedure, after the oil change put in 7 qts oil and 11.2 oz CamGuard.  (Or, 6 qts oil and 9.6 oz CamGuard.)

[Yetti]

Yes the oil can travel up wind inside the engine compartment.   has to do with low pressure and high pressure areas.   after sitting after running, mine will leave a spot on the floor under the tube.

[Bigdaddie]

5 minutes ago, 47U said:

First oil change… so the airplane is new to you?  As @Ragsf15e says, probably spit out the breather.  

If you have an 8 qt sump, and you put in 8 qts plus 16 oz CamGuard, then you were definitely overfilled.  The CamGuard ratio is 1.6 oz per quart of oil, so following Rags15e procedure, after the oil change put in 7 qts oil and 11.2 oz CamGuard.  (Or, 6 qts oil and 9.6 oz CamGuard.)

Had the airplane for about 3 years.  I like to change the oil about every 200hrs or 3 years.  JUST KIDDING!  I bought the airplane mid-annual so it was done at the first annual.  Then it spent 8 months in the avionics shop where they did an annual and thus, my first time just rolled around.  I went a little long @ 45hrs but 20 of that was flying to OSH and back (highway miles).

I guess I screwed up the CamGuard too.  I don't know why but I was thinking it required slightly more than one 16oz bottle and that I was using a little less than the recommended amount.  3.2oz extra won't hurt anything in the short term (I hope).

Thanks for the support everyone!  This group is awesome.

[Ragsf15e]

1 hour ago, Bigdaddie said:

I just did my first oil change myself on my 231.  I ran the airplane pretty hard and checked for leaks and found none.  After I flew it there was oil on the outside of the left nose gear door.  A single paper towel cleaned it up.

I added 8qts of oil plus 16oz of Cam Guard.

Do you think it is just blowing the oil out the breather due to being over filled or spilled oil I didn't catch and clean up?  It seems to me that breather oil would be aft of the cowling. I can't find any leaks in the engine compartment.

One other thought… I’ll look again, but i think my poh says 5-8qts.  6 is already a qt above that, so seems plenty good, no?

ahh, found it:

[Bigdaddie]

23 minutes ago, Ragsf15e said:

One other thought… I’ll look again, but i think my poh says 5-8qts.  6 is already a qt above that, so seems plenty good, no?

ahh, found it:

5qts is getting a bit low for me.  I think they get that number from the engine type certificate data sheet which specifies the minimum amount of oil for operation.  I'm flying to work tonight (airline pilot) and it should be about 1.5 hrs.  I'll post an update when I get to Sydney, AU tomorrow.

[Pinecone]

3 hours ago, Bigdaddie said:

I guess I screwed up the CamGuard too.  I don't know why but I was thinking it required slightly more than one 16oz bottle and that I was using a little less than the recommended amount.  3.2oz extra won't hurt anything in the short term (I hope).

Extra will not hurt.

What I do is take one bottle of CamGuard and two bottles of oil.  I then remove 1.6 ounces of CamGuard from the bottle and put it into one of the quarts of oil.  Repeat with the other bottle.

That way I have a couple of quarts of oil that I can add and no have too little CamGuard.   But if I am flying a trip where an oil change will be done when I get back, I just add plain oil.  Yes, I am a CB.

 

[Ragsf15e]

2 hours ago, Bigdaddie said:

5qts is getting a bit low for me.  I think they get that number from the engine type certificate data sheet which specifies the minimum amount of oil for operation.  I'm flying to work tonight (airline pilot) and it should be about 1.5 hrs.  I'll post an update when I get to Sydney, AU tomorrow.

Oh I agree, 5 is pretty low, I guess I was just trying to say 6 isn’t bad.  I do think 5 is actually Mooney’s limit, continental’s is even lower.  The manufacturer has to allow for some use in flight.  I think there’s some formula for it but I just keep her at 6 and she doesn’t spit out as much.

[Pinecone]

IIRC, FAA requires that the minimum oil level be 1/2 or less than the full level.

This is an explanation why there are many engines, that if filled to full, blow out 1 - 2 quarts almost immediately.  The manufacturer determined the minimum level and made 2x the min = Full

[EricJ]

51 minutes ago, Pinecone said:

IIRC, FAA requires that the minimum oil level be 1/2 or less than the full level.

This is an explanation why there are many engines, that if filled to full, blow out 1 - 2 quarts almost immediately.  The manufacturer determined the minimum level and made 2x the min = Full

Usually what's referenced is that there must be enough oil capacity to run through full fuel tanks at the maximum oil loss rate.    The max loss rate for most Lycomings is around 1.5 hours/quart, and with 8 qts that gets you to 12 hours, which is tank duration plus margin on most Mooneys.

The minimum for Lycomings is usually just enough that the sump can draw oil and not air, so on some airplanes, like an Arrow II, the "m,inimum safe quantity" is 2 quarts for the IO-360 in that aircraft.   Airframe manufacturers can increase those limits, so for many others with similar engines it is higher for whatever reason the manufacturer determined (e.g., margin for uncoordinate flight, etc.).

Lycomings will often blow out oil that is above the drain groove in the bottom of the crank case since it is subject to crankshaft windage there.   For the IO-360s (and many other Lycomings) that's about the six quart level.   

[Fly Boomer]

6 minutes ago, EricJ said:

Usually what's referenced is that there must be enough oil capacity to run through full fuel tanks at the maximum oil loss rate.    The max loss rate for most Lycomings is around 1.5 hours/quart, and with 8 qts that gets you to 12 hours, which is tank duration plus margin on most Mooneys.

The minimum for Lycomings is usually just enough that the sump can draw oil and not air, so on some airplanes, like an Arrow II, the "m,inimum safe quantity" is 2 quarts for the IO-360 in that aircraft.   Airframe manufacturers can increase those limits, so for many others with similar engines it is higher for whatever reason the manufacturer determined (e.g., margin for uncoordinate flight, etc.).

Lycomings will often blow out oil that is above the drain groove in the bottom of the crank case since it is subject to crankshaft windage there.   For the IO-360s (and many other Lycomings) that's about the six quart level.   

Our engines are "air cooled", but without a water jacket, radiator, and coolant pump, it might be more accurate to say "air/oil cooled".  Low oil=high temperature.

[PeteMc]

On 2/27/2025 at 8:25 AM, Bigdaddie said:

I added 8qts of oil plus 16oz of Cam Guard.

So 48oz, 1qt oil & 16oz of Cam Guard, got blown out the oil vent tube. 

You want to put 7qts in max at an oil change.  Run the engine and make sure everything is okay and you may show 6-7 qts.  Let it sit a day or more and then check, where you may find you have MORE than 7qts.  Since you probably ran the engine to get the oil warm before the oil change, all the engine parts were still covered in oil.  It will take a while in the TSIO-360 for that oil to move down out of the engine. 

Edited February 28 by PeteMc

[Bigdaddie]

On 2/28/2025 at 7:35 AM, EricJ said:

Usually what's referenced is that there must be enough oil capacity to run through full fuel tanks at the maximum oil loss rate.    The max loss rate for most Lycomings is around 1.5 hours/quart, and with 8 qts that gets you to 12 hours, which is tank duration plus margin on most Mooneys.

The minimum for Lycomings is usually just enough that the sump can draw oil and not air, so on some airplanes, like an Arrow II, the "m,inimum safe quantity" is 2 quarts for the IO-360 in that aircraft.   Airframe manufacturers can increase those limits, so for many others with similar engines it is higher for whatever reason the manufacturer determined (e.g., margin for uncoordinate flight, etc.).

Lycomings will often blow out oil that is above the drain groove in the bottom of the crank case since it is subject to crankshaft windage there.   For the IO-360s (and many other Lycomings) that's about the six quart level.   

This is from the TSIO360LB Type Certificate Data Sheet:

Oil sump capacity, qt.8. 5 usable at 26° noseup and 5 useable at 18° nosedown

So I would think that 5qts would be the absolute minimum for normal operations; not to say that less than 5qts would be okay at normal flight attitudes.

[Bigdaddie]

On 2/28/2025 at 9:06 AM, PeteMc said:

So 48oz, 1qt oil & 16oz of Cam Guard, got blown out the oil vent tube. 

You want to put 7qts in max at an oil change.  Run the engine and make sure everything is okay and you may show 6-7 qts.  Let it sit a day or more and then check, where you may find you have MORE than 7qts.  Since you probably ran the engine to get the oil warm before the oil change, all the engine parts were still covered in oil.  It will take a while in the TSIO-360 for that oil to move down out of the engine. 

I actually listened to an episode of "Ask the A&Ps" where Paul New stated he never warmed the engine up before changing the oil because you end up retaining much of the dirty oil for reasons you stated above.  I just plugged in my Tanis oil pan pre-heater in for maybe 30 minutes and the oil drained quite nicely.

[Bigdaddie]

I flew 2 hrs and the airplane sat for 3 days.  Oil level: 7.5 qts.  So after flying about 4 hours, just a little oil on the gear door. I think it's getting back to it's happy place.  These engines REALLY don't like to be filled to capacity.  I should know that because I taught students that for years, but now I'm old and stupid.

[PeteMc]

21 hours ago, Bigdaddie said:

I just plugged in my Tanis oil pan pre-heater in for maybe 30 minutes and the oil drained quite nicely.

Sure, if you HAVE a Tanis heater!  

And I get Paul New's point...  But did he clarify how much "old" oil was really retained?  My guess is that it is not much in reality.  And if you're changing the oil frequently, is it really an issue?   Well...  I guess if you're having engine issues and you're always getting all sorts of crap in your oil, it might matter. 

 

[Pinecone]

Mine engine will hold 1 - 2 quarts after running.  I really can't check the oil accurately until the next day.

[Bigdaddie]

Yea Continental engines are crazy at hiding oil.  I get a reading of about 1/2 quart more after 24 hrs of a flight and about a full quart after several days.