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Too Little Oil Usage?

macrafic

Well Known Member
Lots of info on the site relative to average and max oil usage. And when an engine may be broken in using oil consumption as criteria. Could not find anything however on MINIMUM oil consumption.

I did my first oil change at 15 hours on a new engine. I made the decision that the break-in was complete and changed from mineral oil. Since then, I have gone another 17 hours and have only used a half (1/2) quart of oil. Oil color still looks good.

Should I be concerned? Is there such a thing as to LITTLE oil being used?
 
I wold not be concerned with your usage. If you used zero oil in 17 hours I'd probably investigate.
 
My O-290-D2 is the same way. It's spooky. I have Cermichrome cylinders. In the fall, I flew across the Country and back and only used maybe 3/4 qt. of Aeroshell W80. Compression has been 78/80 or better ever since my first flight (3 years ago).
 
My IO-320-D1A has used between 1/2 to 2/3 quart between 25-hour oil changes since new. It used a bit more at higher power settings on a long cross country, but on a lot of my flights to breakfast, etc. I'm puttering along at 2400 rpm or so.
 
Oil

My 0 320 with 10-1 pistons and new Lycoming cylinders is the same or maybe less. No concerns.
 
I had an O-235 that used about 1 qt every 25 hours, and that was from major overhaul to about 600 hours when I sold it. I wish I could tell you we did something special, or had some top secret recipe, but the reality is we bought a lot of new parts, put them together per the book, and had a nice engine as result.

With other planes of I've owned, the frequency of flying has had a dramatic effect on oil usage. If I only flew once every couple weeks I used a lot more oil than if I flew a long cross country.

DEM
 
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Does it matter if you have an air oil separator? I assume so. I am running an ASA vacuum valve (and bypass) and ASA air oil separator, oil consumption is almost zilch. I had it removed for awhile and usage was about a quart or two between oil changes. My engine compartment and belly are much cleaner with this setup installed.
 
No such thing as too little usage. I have owned four planes. Three used almost no oil. One burnt the “normal amount” until I replaced a cracked valve guide and a bad cylinder.
I usually add 7 qts. to my O-360-A1A. It blows 1/2 qt. out the vent in the first hour and then stays at 6 1/2 until the oil change.
 
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My IO-320-D1A has used between 1/2 to 2/3 quart between 25-hour oil changes since new. It used a bit more at higher power settings on a long cross country....

My Aerosport/Superior IO-320 D2A is similar... 1/2 to 1 qt in 31 hours.... been that way for 4+ years now.
 
My IO360 burns about half a quart in 8 hours, surprising really, I run it pretty hard.
 
I typically do not add oil between oil changes with spin on filter recommendation of 50-hours. After engine was rebuilt and broke in correctly, I would go 45-hours before the engine used a quart. Would just change it instead of adding. After 800-hours, it will still go 31 to 35-hours till it needed a quart. Present engine will go over 35-hours till it needs a quart. Have done last two oil changes based on time and not operating hours. Stuff like that happens when you move.
 
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I'm not an expert, but in theory it could be possible to "make" oil if you had a really screwed up fuel pump allowing some fuel to enter the oil system. I think I read of this happening but you should be able to smell the difference and it would show up in an oil sample.
 
I'm seeing about 1.5 to 2 quarts every 50 hours (IO-360-M1B) but this also depends on whether I have been doing aeros or not.

I have the half Raven system on the engine primarily to catch oil when doing stall terns etc. I am venting the blow by oil, water, acids etc. overboard which means I need to clean the belly every 6 months as it accumulates a mist of oily residue

Cheers
 
Lots of info on the site relative to average and max oil usage. And when an engine may be broken in using oil consumption as criteria. Could not find anything however on MINIMUM oil consumption.

I did my first oil change at 15 hours on a new engine. I made the decision that the break-in was complete and changed from mineral oil. Since then, I have gone another 17 hours and have only used a half (1/2) quart of oil. Oil color still looks good.

Should I be concerned? Is there such a thing as to LITTLE oil being used?

Definitely, suggest the engine be disassembled to determine cause of low oil usage. :)
 
I'm not an expert, but in theory it could be possible to "make" oil if you had a really screwed up fuel pump allowing some fuel to enter the oil system. I think I read of this happening but you should be able to smell the difference and it would show up in an oil sample.

This was my thought as well. Things get added to the oil as part of the combustion process.
 
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