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Oil usage

donaziza

Well Known Member
I have an ECI IO 360 engine. 188 HP. How much oil usage is too much? ( No leaks) Or put another way, how many hours should a guy be able to go before adding a quart of oil??
 
Up to a quart an hour can be acceptable, although very annoying.

A quart every 10-15 hours is pretty good, a quart every 3 hours is not that good, but again, not necessarily a problem.
 
From the Lycoming website:

QUESTION: At what rate of oil consumption does continued operation of the engine become a hazard?
ANSWER: Generally speaking, when the oil consumption reaches one quart per hour, corrective action should be taken. However, maximum permissible for each particular engine is listed in the engine operator’s manual.
 
Monitor closely if a big change.

I have an ECI IO 360 engine. 188 HP. How much oil usage is too much? ( No leaks) Or put another way, how many hours should a guy be able to go before adding a quart of oil??

I had an ECI 360 engine with about 900 hours go from a quart per 12-15 hours go to a quart every 6 hours to a quart every 3 hours to a brand new Superior IO360 in about a month.
How old is your engine? Some of their lifters in about 2012-13 time frame were, how to say it, not very well made.
Check you filter very carefully.
 
I would say that an absolute minimum is that you can go from topped off to minimum oil qty over the span of time = full fuel endurance. Most would say that long before that point you are due for a top O/H. Burning that much oil is likely to create enough carbon chunks in the oil pan that the risk of clogging up the finger strainer is realistic in a moderate amount of time. I glazed 2 cylinders after my 320 O/H (creates a pretty significant oil consumption rate) and only ran 10 hours before addressing it. Was shocked by how many carbon chunks I found.

Whenever consumption gets below 1 qt in 10 hours, owners need to be more vigilant on checking the strainer IMHO.

Larry
 
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As above, the allowable oil consumption per Lycoming is dictated by hp and is fairly large.
I would also be concerned if your oil consumption increased precipitously like mine did on the titan x-340. We found this:
 

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One thing to consider as well is various engines have a different “happy level” that they will burn down to then level off. Check what the minimum oil level is by the manufacturer (often way lower than you’d think and not where I’d ever run it) and see if it will just burn down to a level above that and then level off. I’ve often see. 2-4 Qt’s below full as a normal level off depending on engine size / oil capacity where it will burn / blow off down to that level quickly then stop.
 
One thing to consider as well is various engines have a different “happy level” that they will burn down to then level off. Check what the minimum oil level is by the manufacturer (often way lower than you’d think and not where I’d ever run it) and see if it will just burn down to a level above that and then level off. I’ve often see. 2-4 Qt’s below full as a normal level off depending on engine size / oil capacity where it will burn / blow off down to that level quickly then stop.

Good call, I was topping off my IO-360 200HP to 8 quarts and was "burning" down to too quickly for my liking. After talking to a couple of local 360 guys I learned that it would be much happier at 6 quarts. I ran at 6 and my consumption went back to 1 quart every 15 hours. Next good plane wash I realized that topping off to 8 did nothing more than puke the top 2 quarts overboard before it settled happily at 6 quarts.
 
I had an ECI 360 engine with about 900 hours go from a quart per 12-15 hours go to a quart every 6 hours to a quart every 3 hours to a brand new Superior IO360 in about a month.
How old is your engine? Some of their lifters in about 2012-13 time frame were, how to say it, not very well made.
Check you filter very carefully.

The engine is just shy of 1000 hours. I bought the plane from the builder in 2013. I seem to recall, he finished it in 2008, but it only had 98 hours on it in 2013. Been running like a top so far. Took it to my mechanic, he checked for leaks, none, said I was fine. (And I keep it it at no more than 6 quarts). Used to go maybe 15--20 hours before I had to add a quart. Now everytime I fly, say a coupla hours, when I get bsck, I need to put a qt in.
 
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Don,

Something isn't right if it suddenly went from 10-15 hours per quart to 2 hours per quart and there's no obvious leak. Take out the plugs and see if one is really dark and oily. Do a compression check and have it boroscoped. This needs to be investigated.

Rob
 
Used to go maybe 15--20 hours before I had to add a quart. Now everytime I fly, say a coupla hours, when I get bsck, I need to put a qt in.

A significant change in consumption like that is NOT from normal wear. Something inside one or several cylinders has changed. First guess in a broken ring. Changes like that deserve further exploration to determine root cause. Step one is to determine where the oil is going - being burned in cylinders or being blown out of the breather from excessive pressure.

Larry
 
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Immediate compression check is needed. This will tell you where the oil is going if it's being "consumed", internal vs leaking, external. The leaking air from the compression check will be heard in the exhaust, intake and/or breather. depending on where the leak is heard the plan of attack can be formed around the findings
 
Immediate compression check is needed. This will tell you where the oil is going if it's being "consumed", internal vs leaking, external. The leaking air from the compression check will be heard in the exhaust, intake and/or breather. depending on where the leak is heard the plan of attack can be formed around the findings

I disagree for several reasons. A compression check will not always identify why an engine is consuming oil, though it does help to identify some causes of why it is blowing oil out of the breather. A good example is a broken or siezed oil ring. NO change in compression readings, but oil consumption goes off the charts; Usually produces blue exhaust that smells oilly. ANother is glazed walls. Perfect compression, but burns a lot of oil. leakage past the valves does nothing to tell you the source of oil consumption.

Larry
 
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I disagree for several reasons. A compression check will not always identify why an engine is consuming oil, though it does help to identify why it is blowing oil out of the breather. A good example is a broken or siezed oil ring. NO change in compression readings, but oil consumption goes off the charts; Usually produces blue exhaust that smells oily. Another is glazed walls. Perfect compression, but burns a lot of oil.

Larry

And should be noticed on the plugs....mainly the lower especially if it is fired with a mag. Take a look at your plugs.
 
Yeah, when my ring broke in the prior post pics, compression was good, oil consumption went to a quart an hour suddenly and the affected cylinder plug was oily.
 
The engine is just shy of 1000 hours. I bought the plane from the builder in 2013. I seem to recall, he finished it in 2008, but it only had 98 hours on it in 2013. Been running like a top so far. Took it to my mechanic, he checked for leaks, none, said I was fine. (And I keep it it at no more than 6 quarts). Used to go maybe 15--20 hours before I had to add a quart. Now everytime I fly, say a coupla hours, when I get bsck, I need to put a qt in.

This brings back memories. My RV-8 motor was built from an ECI package by Mattituck with Cerminil cylinders back in 2005. It rarely got better than about 6-7 hours per quart, despite a textbook break-in, At 1400 hours, I came back from a trip from Dallas to Houston, and had to add a full quart to get back to where it was before take-off, and that was a clear sign something was wrong.

It turned out that the rings were delaminating - they had a special coating on them to make them work with the Cerminil, and it was flaking off - we found lots of bare spots on the rings when we replaced the cylinders with straight nitrided cylinders from Lycoming - and all was well again, and has stayed that way.

No more Cerminil for me, and if that is what you have, you might have to bite the bullet and spring for some jugs.

Paul
 
I was planing to fly Atlanta-Milwaukee this Thursday, an 8 hour round trip. You guys think I'm safe?? Or stay home and head back to my mechanic.:confused::confused:
 
I was planing to fly Atlanta-Milwaukee this Thursday, an 8 hour round trip. You guys think I'm safe?? Or stay home and head back to my mechanic.:confused::confused:

My mentor mechanic always answers questions like that with "That's pilot stuff" (G rated version). So you are really only asking yourself that question. Since it is an ECI engine, I would personally do a compression check and then camera scope the cylinders. I was in your same shoes two years ago with ECI cylinders (Americas Aircraft Engines Eagle IV assembly). Had I known then what I know now about ECI Titan issues I would have swapped out my ECI cylinders for all new steel cylinders. I continued flying it in ignorant bliss. Alas I had to do a complete TDI of the engine when the nickel coating came off in #1. That was much more expensive than just swapping out the cylinders prior to the problem.
 
I guess I'm really lucky with my engine - I change oil at 50 hours, and only add one quart around the 30 hour mark. Anything more than 6 quarts will go out the breather, but it will run between 5 and 6 quarts forever.
 
Ignore any hysteria and approach the problem logically.

It's only a machine, nothing magical or mysterious about it.

Start with this podcast: https://youtu.be/lduHFzZBzGw

Then pull the top plugs and get a borescope in there. Look for excessive oil pooling in the bottom of the cylinders or dark streaks that could indicate a stuck ring. Longitudinal scratches could be a broken ring. If nothing is obviously wrong go for the compression test and maybe a ring wash.

I'd at least scope it before flying again, that can tell you a lot and it only takes an hour. You can get a great vividia scope on Amazon for 200 bucks. https://youtu.be/7R-dAmv9VZk
 
Ignore any hysteria and approach the problem logically.

It's only a machine, nothing magical or mysterious about it.

Start with this podcast: https://youtu.be/lduHFzZBzGw

Then pull the top plugs and get a borescope in there. Look for excessive oil pooling in the bottom of the cylinders or dark streaks that could indicate a stuck ring. Longitudinal scratches could be a broken ring. If nothing is obviously wrong go for the compression test and maybe a ring wash.

I'd at least scope it before flying again, that can tell you a lot and it only takes an hour. You can get a great vividia scope on Amazon for 200 bucks. https://youtu.be/7R-dAmv9VZk

This video you referred me to, turned out to be excellent. Its a Mike Busch EAA webinar from the year 2014. I don't have oil on the belly, no leaks inside the cowling, so its got to be door number 3, ie oil being sucked into one combustion chamber thru a worn intake valve guide and a bad intake valve oil seal (Borescope) OR getting into combution chamber because of stuck (typically lead fouled) piston rings (Do Ring wash) One thing he suggested was to put my fingers inside my exhaust pipes. I guess its supposed to be dry. Mine are kinda gooy/oily feeling. A telltale sign.
 
This video you referred me to, turned out to be excellent. Its a Mike Busch EAA webinar from the year 2014. I don't have oil on the belly, no leaks inside the cowling, so its got to be door number 3, ie oil being sucked into one combustion chamber thru a worn intake valve guide and a bad intake valve oil seal (Borescope) OR getting into combution chamber because of stuck (typically lead fouled) piston rings (Do Ring wash) One thing he suggested was to put my fingers inside my exhaust pipes. I guess its supposed to be dry. Mine are kinda gooy/oily feeling. A telltale sign.

This is the problem with diagnosing via someone's video. Yes, oilly exh pipes helps to confirm that too much oil is getting into the combustion area. However, there are numerous causes beyond a stuck ring. It could be a broken ring, it could be delamination of the ring, if coated, it could be a problem with the cyl wall, including delamination, if coated, a blocked oil return line from a rocker box, etc. IMHO, there is not a lot of oil flow to the rocker box in a lyc and even if there was, gravity pulls it away from the guide, unlike most other engines. Therefore, pulling oil in via the intake valve doesn't seem like a possible source of oil consumption in a Lyc, beyond trace amounts. Definitely not enough to burn .5 qt/hr. Remember that the same valve didn't have a problem for the last 1000 hours. That said, a blocked return line will flood the rocker area and oil will now flow past the guides and make it to the combustion chamber.

The sudden change in consumption points to a single traumatic event. Untill you know what it is, it is hard to know whether or not you can expect it to be stable or get worse. I don't think that I would take a four hour trip until I knew the cause and could confirm that things are stable in the new state.

You would think Mike would know better, but the Lyc does not use oil seals on the valves. The clearance can get quite large and still not allow oil past it. Also, rings get stuck from carbon (coked oil) not lead. Lead is a naturally low friction material and very soft. Have you ever cleaned out a ring land? It is not like popping lead balls out of a sparkplug. The stuff is rock hard and sticks like an adhesive. Quite the chore to clean out.

Larry
 
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For those of you who may be interested, (probably not): My oil usages weren't quite as bad as I originally thought. ( I had just winged the math very quickly).
1 qt at 5.9 hours
1 qt at 6.1 hours
1 qt at 14.2 hours
1 qt at 7.8 hours
1 qt at 4 hours

Went to my mechanic today:

1> Checked exhaust pipes- not gooey like I thought
2> Checked all spark plugs--good
3> Cylinder compressions were:
#1 80/80
#2 78/80
#3 79/80
#4 79/80

Borescoped cylinders to check pistons,
cylinder walls
valves. No detects noted

Spark plugs show no defects

Exhaust pipes clean and free of oil residue.

Hope this helps someone else.

Oh, and what Paul Dye said back on post 16---I don't have those kind of cylinders, it turns out.
 
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With a high of 1qt in 4 hours to a low of 1qt in 14 hours, there is something that is not right.

My oil consumption (Phillips XC) is over 20hrs per qt and is very consistent. As already mentioned, comp reading in the high 70's can still be achieved with bad oil rings.

If you don't have oil on the belly, then you are burning it..... at a ratio of about 1/2 of a modern two stroke.
 
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With a high of 1qt in 4 hours to a low of 1qt in 14 hours, there is something that is not right.

My oil consumption (Phillips XC) is over 20hrs per qt and is very consistent. As already mentioned, comp reading in the high 70's can still be achieved with bad oil rings.

If you don't have oil on the belly, then you are burning it..... at a ratio of about 1/2 of a modern two stroke.

+1

For a 1000 hours it burned 1 qt in 15-20 hours. Over a very short period of time, it now burns a qt in around 4-6 hours. Know nothing about your mechanic, but I would NOT walk away thinking all is normal; Something significant has changed. Not saying it is a ticking time bomb, however, I would want to know what it is so that I could decide if it is stable or expected to get worse. If you are not showing signs of it burning, it is possible it is coming out the breather. An oil separator can keep the belly clean even with a significant load of oil coming out of the breather.

Larry
 
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Don, you know the VAF is not going to let you off that easy! :D

One thing you might try if not already doing it, is to send an oil sample to blackstone labs to see how much metal they see in the oil. I'd also recommend cutting open the filter and checking the oil pickup screen for anything unusual.

About the borescope, do you know if the mechanic has one that can look back on the valves? That might also be interesting information.
 
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