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Oil Quantity (IO-360)?

dmat

Well Known Member
Advertiser
Hi All,

basic question but figured I ask.... My IO360 manual states no more then 8qts and some ridiculous number of no less then 4qts.

I have been hovering at about 6 qts. Is that acceptable or should I play it safe and keep it at 7?

Thanks,
D
 
6

6 quarts is adequate for operation in all attitudes, and has always been my minimum level at takeoff. In my experience, and often reported, 7 or 8 quart level leads to venting overboard to a stable level at 6. Look to your engine manual for more info. I think you will find that minimum for takeoff is 4 quarts, just FYI -- not recommending.
 
Cold air sump?

Does a Superior cold air sump change anything concerning the quantity?

My guess is that due to its construction, the oil pan itself lost a bit of the volume (to take oil) compared to a standard oil pan.
Therefore the level of the oil, lets take 6 qts, is slightly higher and will be vented overboard.......

So what is the oil quantity if you use a superior cold air sump?

What do the guys do who already fly behind an IO-360 with superior cold air sump?

Mit Fliegergru
 
Does a Superior cold air sump change anything concerning the quantity?

My guess is that due to its construction, the oil pan itself lost a bit of the volume (to take oil) compared to a standard oil pan.
Therefore the level of the oil, lets take 6 qts, is slightly higher and will be vented overboard.......

So what is the oil quantity if you use a superior cold air sump?

What do the guys do who already fly behind an IO-360 with superior cold air sump?

Mit Fliegergruß

You'll likely need to re-calibrate your dipstick to the new sump but the amount should not change, if I recall.
 
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re-calibration of the dipstick is necessary!

I am just curious about the quantity!

Mit Fliegergru
 
5 qtz on the dip stick (in the sump), +/- 1 qt in the filter.
Any more and mine will just dump the extra.
When I change oil, I fill with 6 qtz with a new filter. It will always find its level on the dip stick right at or near 5.
 
re-calibration of the dipstick is necessary!

I am just curious about the quantity!

Mit Fliegergru?

An email to Superior asking if the capacity for my O360-A4M would remain at 8 qts received the following response:

"Yes, it remains at the same capacity"

I plan to do this upgrade in the next 6 months.
 
Careful with the original dipstick for the IO-360-M1B. As the Lyc service bulletin about dipstick replacement intimates, the level marking below 6 Qt is incorrect. I have not changed mine yet but during an oil change after the SB, I filled one quart at a time and watched the dipstick. The 4 Qt mark is definitely in the wrong place and the area under the 6 Qt is not visually linear. Actual contained oil drops really quickly when the oil shows below 6 Qt.

As a result, I have gotten into the habit of keeping the level right at 6 Qt by adding 1/2 Qt when needed.
 
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A very respected sage who cashed quite a few paychecks from Lycoming Engines taught me that every engine has a 'happy spot' when it comes to oil level. The IO-360 I fly is around 5.5 qts. The O-320 I fly is around 4.75 qts. Anything more than those quantities on those particular airplanes ends up on the belly of the airplane. YMMV.
 
When/how to measure oil quantity?

This may not be significant but I've often wondered if the marking on the dipstick indicate how much oil is in the oil pan, or in the engine?

Assume that the oil has just been drained and the filter replaced so there's no oil in the filter. You put in 8 qts new oil and let it settle. After first run, the filter will fill and I assume not drain back to pan too quick. Will the dipstick then read less by the equivalent of what the filter is holding?

Bevan
 
This may not be significant but I've often wondered if the marking on the dipstick indicate how much oil is in the oil pan, or in the engine?

Assume that the oil has just been drained and the filter replaced so there's no oil in the filter. You put in 8 qts new oil and let it settle. After first run, the filter will fill and I assume not drain back to pan too quick. Will the dipstick then read less by the equivalent of what the filter is holding?

Bevan

The dipstick can only measure what is in the sump in the orientation the engine is in at the time. It then depends on whether or not it was calibrated for the application and/or systems installed.
There is a slight difference between a tail dragger and a nose wheel. Floats, Tundra Tires, filter systems, oil cooler capacity, etc... all effect what the dipstick see's as an "oil level".
The only way to know for you is to do a calibration check. You can then mark your dipstick, typically by notching with a file, if it reads differently than marked.
Lycoming specifically states to add one quart if using a filter for max and min oil levels measured by the dipstick.
 
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Lycoming specifically states to add one quart if using a filter for max and min oil levels measured by the dipstick.

Can you point us to the reference/document for this?

FWIW, mine tends to vent anything above 6 on the dipstick, then runs around 12-15 hrs/qt. I add a quart when it gets below around 1/2 way between 6 and 4 on the (new per SB) dipstick. Oil analyses at ~500 hours now have always been excellent.
 
Yep.

A very respected sage who cashed quite a few paychecks from Lycoming Engines taught me that every engine has a 'happy spot' when it comes to oil level. The IO-360 I fly is around 5.5 qts. The O-320 I fly is around 4.75 qts. Anything more than those quantities on those particular airplanes ends up on the belly of the airplane. YMMV.

You have a good sage answer. A lot of things go into where the oil level likes to stabilize and not throw off any more to crank-case venting. How old is it, that pistons does it have, how hard to you push it, how do you fly ( flat and level or up-side down a lot. Anyway, If you are going on a long cross country that extra two Quarts is there for safety if you spring a leak and in some cases for cooling. Ours likes 6 quarts for just local flying and 4 is the least I let it go and most of the time I will add one at 5 quarts, just to feel good about things around the patch. Yes it is an IO-360 with am "M" sump. Just what we do, your call, your engine. Yours, R.E.A. III #80888
 
for the 4 bangers I consider 6 "Full", and add when it drops below 4.

What Toolbuilder said above. I also use 4 as my "add a quart" point for 4 cylinder Lycomings. Angle valve, parallel valve, narrow deck, wide deck with oil filter or just screen. 4 is my trigger. That usually makes a youthful flight instructor's head explode since the dipstick has an "8" on it. The same guy who uses full rich mixture on takeoff no matter the density altitude because the checklist says so.

Jim
 
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