How full is full? Settle a debate
- Thread starter jcartwright99
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Full is the capacity the manual states. Dipsticks can be wrong.
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MolaKule
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Originally Posted By: jcartwright99
...I say as long as it is either in the crosshatched section or a little above you should be fine. I told him you never want to overfill or be at that over or into that top hole because then you are overfilling it (and that can be bad)...
This is correct.
Too many people have this "more is better" attitude when it comes to many things in life.
...I say as long as it is either in the crosshatched section or a little above you should be fine. I told him you never want to overfill or be at that over or into that top hole because then you are overfilling it (and that can be bad)...
This is correct.
Too many people have this "more is better" attitude when it comes to many things in life.
You have inadvertently opened a topic that's been visited many times here with the usual conflicting advice.
Me, I fill the sump with the recommended refill capacity and call it good.
I'll check the oil level every thousand miles or so.
While some will obsessively add oil a quarter quart at a time, I won't do so until the level is down to add on the dipstick, which typically won't happen during an OCI with my cars.
Either way, as long as the oil level is somewhere between add and full on the dipstick, the engine will be fine.
There is a reason that manufacturers have provided a range of acceptable oil levels on engine oil dipsticks and it isn't because there is any need to maintain the oil level at the full mark all the time everywhere.
Over thousands of miles of use, you come to know what to expect from an engine and you'll know how many miles will pass before any oil adds will be needed, if they're needed at all.
Me, I fill the sump with the recommended refill capacity and call it good.
I'll check the oil level every thousand miles or so.
While some will obsessively add oil a quarter quart at a time, I won't do so until the level is down to add on the dipstick, which typically won't happen during an OCI with my cars.
Either way, as long as the oil level is somewhere between add and full on the dipstick, the engine will be fine.
There is a reason that manufacturers have provided a range of acceptable oil levels on engine oil dipsticks and it isn't because there is any need to maintain the oil level at the full mark all the time everywhere.
Over thousands of miles of use, you come to know what to expect from an engine and you'll know how many miles will pass before any oil adds will be needed, if they're needed at all.
Originally Posted By: Cujet
When it's full, after a proper oil and filter change using 9 quarts, the dipstick reads 8 quarts.
Lycoming allows the engine to run, in flight, as low as 4 quarts. Testing shows that the engine will not suffer oil pressure problems in any aspect of flight until it's at 3 quarts on the dipstick.
The bottom line is that every engine has a significant safety margin built in.
Correct answer here ^^^.
Your sump has a large safety margin, while your dip stick is not a precision instrument.
How would you fill a bath tub with a level marker ?
One inch low and you will never get clean, one inch high and you are going to drown ?
When it's full, after a proper oil and filter change using 9 quarts, the dipstick reads 8 quarts.
Lycoming allows the engine to run, in flight, as low as 4 quarts. Testing shows that the engine will not suffer oil pressure problems in any aspect of flight until it's at 3 quarts on the dipstick.
The bottom line is that every engine has a significant safety margin built in.
Correct answer here ^^^.
Your sump has a large safety margin, while your dip stick is not a precision instrument.
How would you fill a bath tub with a level marker ?
One inch low and you will never get clean, one inch high and you are going to drown ?
Originally Posted By: jcartwright99
My friend and I got into a spirited discussion on how much oil you should have in there. He claims it should always be right at the top Max hole and you if you aren't, are low on oil. I say as long as it is either in the crosshatched section or a little above you should be fine.
I say you are correct. I'm sure the engineers are well aware that neither the dipstick nor the manual service fill capacity is "exact." Between different sized filters, draining time, not being level when measuring, being careless with a dipstick, a dipstick being hard to read, and so forth, there's plenty of room for inaccuracy.
What's "right on the dot" here and now may not be the same ten minutes from now. With the G37, I always check it after it's been sitting all night in the same place in the garage to minimize those little issues. That being said, the taxis were always checked after being off for no more than 5 minutes after running all day. You make due with what you have.
Listen to Trav - a few ounces over or under are immaterial. If he worried about that, he'd never get anything else done in his life.
And yes, overfilling is not a good idea.
My friend and I got into a spirited discussion on how much oil you should have in there. He claims it should always be right at the top Max hole and you if you aren't, are low on oil. I say as long as it is either in the crosshatched section or a little above you should be fine.
I say you are correct. I'm sure the engineers are well aware that neither the dipstick nor the manual service fill capacity is "exact." Between different sized filters, draining time, not being level when measuring, being careless with a dipstick, a dipstick being hard to read, and so forth, there's plenty of room for inaccuracy.
What's "right on the dot" here and now may not be the same ten minutes from now. With the G37, I always check it after it's been sitting all night in the same place in the garage to minimize those little issues. That being said, the taxis were always checked after being off for no more than 5 minutes after running all day. You make due with what you have.
Listen to Trav - a few ounces over or under are immaterial. If he worried about that, he'd never get anything else done in his life.
And yes, overfilling is not a good idea.
Whatever -as long as it's in the operating zone (cross hatch), it's good to go. All else is just smoke ...
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Originally Posted By: ARCOgraphite
Safe OP is between 1/2 down the crosshatch and full.
Safe is generally anything over 2 quarts on a typical 4 cylinder and about 3 quarts on larger engines.
When I purchase a used car, I always check the oil. I walked away from an awesome car when I discovered that it had no visible oil. I took it for a great test drive and was very happy with the car. Oil pressure looked perfect. Probably had about 2 quarts total in the sump. No issues at all. Even so, I passed on the car and found a better one.
Safe OP is between 1/2 down the crosshatch and full.
Safe is generally anything over 2 quarts on a typical 4 cylinder and about 3 quarts on larger engines.
When I purchase a used car, I always check the oil. I walked away from an awesome car when I discovered that it had no visible oil. I took it for a great test drive and was very happy with the car. Oil pressure looked perfect. Probably had about 2 quarts total in the sump. No issues at all. Even so, I passed on the car and found a better one.
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Originally Posted By: bigj_16
Isn't this more of a philosophical debate? Is it a half quart above the low mark, or a half quart below the full mark?
But the thing is it a half quart from add or a half quart from full?
Isn't this more of a philosophical debate? Is it a half quart above the low mark, or a half quart below the full mark?
But the thing is it a half quart from add or a half quart from full?
As for me and my house, if any of my cars require partial qts I merely round up to the nearest 1/2 qt.
For example, 6.7 qts go to 7: 5.3 go to 5.5: 5.7 goes to 6: etc. That's how I roll....
I keep all my leftovers at half quarts. Why? Because I want to and somehow my mind feels better with uniformity.
For example, 6.7 qts go to 7: 5.3 go to 5.5: 5.7 goes to 6: etc. That's how I roll....
I keep all my leftovers at half quarts. Why? Because I want to and somehow my mind feels better with uniformity.
Originally Posted By: JohnnyJohnson
Originally Posted By: bigj_16
Isn't this more of a philosophical debate? Is it a half quart above the low mark, or a half quart below the full mark?
But the thing is it a half quart from add or a half quart from full?
Nope, it just means the oil pan is too big.
Originally Posted By: bigj_16
Isn't this more of a philosophical debate? Is it a half quart above the low mark, or a half quart below the full mark?
But the thing is it a half quart from add or a half quart from full?
Nope, it just means the oil pan is too big.
Full is the top area of the cross hatching or the "full" dot, marker, indentation etc.
Half a quart low on most passenger vehicles would mean the oil level is halfway between the low marker and the full marker. (Still within a safe range obviously.)
As others have said, anything a little above or below won't hurt anything. Technically, I would say one is safe until oil is no longer on the dip stick, but I wouldn't want to test that theory on anything I own either. This may also depend on the size of the sump too.
*I don't think the non BITOG public worries about this. They are either on 3k OCI's so consumption to below the low mark isn't an issue/ they don't care or feel it's their problem OR they have new vehicles that are dealer serviced and don't consume anything between changes.
OP: When it comes to oil changes, your friend is a putz.
Half a quart low on most passenger vehicles would mean the oil level is halfway between the low marker and the full marker. (Still within a safe range obviously.)
As others have said, anything a little above or below won't hurt anything. Technically, I would say one is safe until oil is no longer on the dip stick, but I wouldn't want to test that theory on anything I own either. This may also depend on the size of the sump too.
*I don't think the non BITOG public worries about this. They are either on 3k OCI's so consumption to below the low mark isn't an issue/ they don't care or feel it's their problem OR they have new vehicles that are dealer serviced and don't consume anything between changes.
OP: When it comes to oil changes, your friend is a putz.
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