For the engine experts-Oil Level

Morgan3820

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For the engine experts. I have a 0-320. When I add oil, the oil level quickly seems to drop from the original 7 qt. level to stabilize at 6 qts. I am guessing that the qt. I added blows out the vent tube. 6 qts. is the minimum operating level. Is there any way that I can raise the oil level to a higher amount? I recall the planes I trained in usually settled in somewhere around 7 qts.
 
For the engine experts. I have a 0-320. When I add oil, the oil level quickly seems to drop from the original 7 qt. level to stabilize at 6 qts. I am guessing that the qt. I added blows out the vent tube. 6 qts. is the minimum operating level. Is there any way that I can raise the oil level to a higher amount? I recall the planes I trained in usually settled in somewhere around 7 qts.
Where are you getting a minimum oil level of 6 qts in a o-320? I think an o-320 min oil level is just 2 qts.

Mine will tend to blow out til around 6 qts and then stabilize also. I just tend to refill when under 5.5 qts.
 
That's where it sits on the PA-28-151/160 I fly. The minimum is 2qt if I really the POH correctly.
 
For the engine experts. I have a 0-320. When I add oil, the oil level quickly seems to drop from the original 7 qt. level to stabilize at 6 qts. I am guessing that the qt. I added blows out the vent tube. 6 qts. is the minimum operating level. Is there any way that I can raise the oil level to a higher amount? I recall the planes I trained in usually settled in somewhere around 7 qts.

This is completely typical and why everyone tops them to 6 quarts. 6 quarts is NOT the minimum operating level according to Lycoming. IIRC Lycomings instructions are to not leave the ground with less than 2 quarts, and you should add a quart for each hour you intend to fly.

I run them between 5 & 6 quarts.
 
Lol, Three identical answers in a row, I think we should just lock the thread before it goes stupid. :rofl: You have the answer you need. You have no problems. The engine stabilizes where it wants between 5&6 quarts. I typically add oil at 4 quarts or top to 6 for a long trip. This is how most everybody I have ever met with an O-320 handles it, and the service record on it is good, so no worries. ;)
 
Lol, Three identical answers in a row, I think we should just lock the thread before it goes stupid. :rofl: You have the answer you need. You have no problems. The engine stabilizes where it wants between 5&6 quarts. I typically add oil at 4 quarts or top to 6 for a long trip. This is how most everybody I have ever met with an O-320 handles it, and the service record on it is good, so no worries. ;)

And the belly of the plane stays ALOT cleaner too... At least it did on my 0-320-E3D in the Warrior...
 
Before we lock the thread, can I ask the same question about a Continental IO520? When I bought it, it had just less than 10 qts on the stick (it holds 12 qts). After about 20 hours, it shows just over 9 qts, and it is still really clean. I think it has about 35 hours since the last oil change and about 80hrs total on the engine. Should I have the oil changed or just add a qt. I am putting it in for annual in about a month anyway. I expect to add about 10 hours by then.
 
Before we lock the thread, can I ask the same question about a Continental IO520? When I bought it, it had just less than 10 qts on the stick (it holds 12 qts). After about 20 hours, it shows just over 9 qts, and it is still really clean. I think it has about 35 hours since the last oil change and about 80hrs total on the engine. Should I have the oil changed or just add a qt. I am putting it in for annual in about a month anyway. I expect to add about 10 hours by then.

Rule of thumb for any engine is the mark below the top mark is where it stabilizes. There are some minor differences in level that come from differences in cowlings, so the best thing to do is take some short flights and monitor consumption heading toward the minimum and find where your engine settles in.
 
Oil seperators? Can certified planes add them without an STC?

Depends on the TCDS I would suppose. The Air Sep comes with one. Unless you have a wet pump though, if you need an Air Sep unit, you probably need a nose seal.
 
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Depends on the TCDS I would suppose. The Air Sep comes with one. Unless you have a wet pump though, if you need an Air Sep unit, you probably need a nose seal.

:confused:

I dont understand. What does the landing gear have to do with an air oil sperator? :eek:
 
:confused:

I dont understand. What does the landing gear have to do with an air oil sperator? :eek:

Nose of the case/crankshaft seal behind the prop. When they dry/shrink/deteriorate the high pressure in the area flows through the seal and crank seeking the low pressure at the end of the vent tube.

I had to do them on the 310. I knew I would have to when I bought it, cost $300 to do both and I had them done at the annual right before the final flight. It was funny, the inspectors and I were just talking looking at the plane (everything that had to be established was accomplished with my first three words, "I ****ed up", after that it was pretty much shooting the **** until the plane was up and we towed it away.) and I pulled the dipsticks. The FSDO dude laughs and asked me if I was planning on flying out.:lol: I told him about having the seals done and being curious if it had cured the oil consumption problem; it had.
 
I'm lost.

Can you read a water tower and tell me where you are? Can you hit Ident for me?

The Nose Seal is on the engine, it has nothing to do with gear. It is what seals the high pressure air that cools your engine from your crank case (it will not leak oil in flight typicality). When that air flows thought the crank case, it blows oil out with it.
 
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I run a mooney with io360 and fill to 6 add at 4qts.....works a lot better.

Now if you have a plane that uses a lot of oil, keep more in it on long flights.

It would be embarrassing to run out of oil before gas :)
 
I run a mooney with io360 and fill to 6 add at 4qts.....works a lot better.

Now if you have a plane that uses a lot of oil, keep more in it on long flights.

It would be embarrassing to run out of oil before gas :)

The Dromader was like that, and it had a big oil tank.:rofl:
 
Any exceptions to the rule of thumb of 1/2 the dipstick max capacity is an adequate minimum?
 
My O-320 stabilizes at 6-6.5 so that is where I fill it to. My O-300 stays at 7 all the time.


Jim R
Collierville, TN

N7155H--1946 Piper J-3 Cub
N3368K--1946 Globe GC-1B Swift
N4WJ--1994 Van's RV-4
 
Oil seperators? Can certified planes add them without an STC?

It's always better to have the paper, because you know some one will call it a major alteration.
 
Any exceptions to the rule of thumb of 1/2 the dipstick max capacity is an adequate minimum?

Lycomings pretty much are all 2 quart minimum for the 4 cylinders, and 4 quart for 6 cyl, and Max is 8 & 12, so that makes 4 and 6 the midpoints, so following the Lycoming rule, if you were planning a 2 hour flight or less, yes, that would be an adequate minimum. Reality is if you are consuming a quart in 10 hrs, you're fine for the fuel range. Personally I just top them when the need a quat to get to the stability point.
 
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I can run 6, 7, 8, 9, or 10 quarts in the tank on the E-225.

Dry sump. Low windage. Nice.....
 
A question..

If your engine will not hold the proper oil level, and drops a couple quarts in an hour doesn't that engine exceed the oil usage per the manuals ?

Isn't some thing wrong with it ?
 
A question..

If your engine will not hold the proper oil level, and drops a couple quarts in an hour doesn't that engine exceed the oil usage per the manuals ?

Isn't some thing wrong with it ?

No, not really. There is no requirement to fill to the top mark. As long as you find a spot that will keep you above minimum for th duration of the flight and be within consumption parameters, you're fine.
 
Lycomings pretty much are all 2 quart minimum for the 4 cylinders, and 4 quart for 6 cyl, and Max is 8 & 12, so that makes 4 and 6 the midpoints, so following the Lycoming rule, if you were planning a 2 hour flight or less, yes, that would be an adequate minimum. Reality is if you are consuming a quart in 10 hrs, you're fine for the fuel range. Personally I just top them when the need a quat to get to the stability point.



What about Continental?
 
No, not really. There is no requirement to fill to the top mark. As long as you find a spot that will keep you above minimum for th duration of the flight and be within consumption parameters, you're fine.

How do say that when an engine uses/ looses/ more than the manuals set forth. it is airworthy?
 
How do say that when an engine uses/ looses/ more than the manuals set forth. it is airworthy?

If it never stabilizes and continues to take it below minimum at defined excessive rate, then the engine fails the test. If it never hits minimum it never fails the test.
 
If it never stabilizes and continues to take it below minimum at defined excessive rate, then the engine fails the test. If it never hits minimum it never fails the test.

you just keep thinking that..
 
you just keep thinking that..

I don't have to. There is no defined criteria which means I can use whatever method I please that I can defend.

I'll give you another one out of the book though. The factory allows for 1 quart per hour. I fill to the full 8 quarts and fly 4 hours. I find 6 quarts in my engine. It passes the test.

At this point Imauit playing because this is another of your pointless inane arguments. Every plane on every ramp is 2 quarts low. I'm done playing now.
 
I believe Tom is hinting at the maximum oil consumption per hour per HP as set forth by Lycoming in S.I. 1427B:
.006 x BHP x 4 divided by 7.4 = Qt./Hr
 
I believe Tom is hinting at the maximum oil consumption per hour per HP as set forth by Lycoming in S.I. 1427B:
.006 x BHP x 4 divided by 7.4 = Qt./Hr

I'd like to see Henning defend against that in any NTSB hearing.
 
I don't have to. There is no defined criteria which means I can use whatever method I please that I can defend.

that's just it, you can't.

I'll give you another one out of the book though. The factory allows for 1 quart per hour. I fill to the full 8 quarts and fly 4 hours. I find 6 quarts in my engine. It passes the test.

Show me any engine manufacturer that allows a qt per hour.
 
Just so every body knows, I do realize there are a great many engines that will discharge oil to a point.

My question was "Is that a discrepancy that should be corrected?" Where do you draw the line as to how much is too much?

As has been pointed out, the factory has given us a usage limit. Has any one ever checked their engine usage to see if it exceeds the factory numbers?
 
I will see if I can find the reference, but I read that during some of the engine certifications oil capacity was calculated as follows:

Oil capacity should allow for 1 qt./hr. consumption for available fuel on board and still have 2X the minimum quantity for safe engine operation.

Lycoming 320/360 engines 8 qts. total, 4 hrs. fuel on board, 2 qts. minimum to run.

If I find the reference, I will post it.
 
I believe Tom is hinting at the maximum oil consumption per hour per HP as set forth by Lycoming in S.I. 1427B:
.006 x BHP x 4 divided by 7.4 = Qt./Hr

I really don't care as it's just one of his stupid, inane, pointless points that does nothing but try to confuse or annoy people. If it blows out some excess and stabilizes at 6 quarts, your engine is ****ing fine, period. What is the point in trying to intoduce doubt and confusion to that?:dunno: It's ****ing asinine and I'm not playing with him on it anymore. It goes against the purpose of this board, or at least what it should be for.

Want to have a stupid argument, that's what Spin Zone is for.
 
I really don't care as it's just one of his stupid, inane, pointless points that does nothing but try to confuse or annoy people. If it blows out some excess and stabilizes at 6 quarts, your engine is ****ing fine, period. What is the point in trying to intoduce doubt and confusion to that?:dunno: It's ****ing asinine and I'm not playing with him on it anymore. It goes against the purpose of this board, or at least what it should be for.

Want to have a stupid argument, that's what Spin Zone is for.
So, You can't answer the questions.
 
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