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How do you fully drain the IO360 Crankcase?

Dandlac58

Well Known Member
Hi Van's Friends,

At the risk of exposing my neophyte Lycoming engine knowledge, I have to ask what probably a lot of you may find to be a silly question, but this is my first oil change on my airplane (I am not the builder, I bought this beautiful bird, Super Tweety)... but here goes:

My IO-360 has a twist and push up oil drain valve at the pilot's side front of the engine. However it is not at the very bottom of the crankcase - as the bottom of the crankcase appears to about 3 inches lower, just below the level where the air intake pipes run through the crankcase from the throttle body. So, it appears to me there is a lot of oil still in the crankcase below the level where my drain valve is located.

There is no drain plug at the very bottom of the engine, or Im AFU and missing something?

Thanks in advance for your assistance.

Dan
 
Photo would be good, but I will take a stab at this.

Is there another drain location in the lower part of the sump? If so, probably has a square head plug in it.

If so, is there room to put the drain valve into the plugged hole? Plug would then go into the hole where the drain valve was.

Another thought is that you may have a cold air sump, and what you are looking at is actually the intake manifold area.
 
Oil screen?

Have u found the oil screen? On my io360 it’s at the back starboard side. Lowest point on my 7A. U should be removing that plug and cleaning the screen. May drain any remaining oil there.
 
Sounds like you have a horizontal induction engine with the throttle body pointing forward. If so, the oil sump is above the intake manifold plenum. In the 3" below the drain plug, there is just an air plenum (so no oil there). Does your sump look like the one below? If so, there's no oil below the drain plug.

Capture.JPG
 
Oil screen?

Okay, PilotKMS, I did see this plug on the back on the starboard side of the bottom of the crankcase, at about the same height as the drain valve at the front port side of the engine. It has safety wire attached to it. So, Im supposed to remove that plug also to clean a screen inside? Do you just route a long funnel up in there to try to catch the oil before it runs out over everything below it?

Have u found the oil screen? On my io360 it’s at the back starboard side. Lowest point on my 7A. U should be removing that plug and cleaning the screen. May drain any remaining oil there.
 
Chock the mains, and raise the tail to level flight. You should also be pulling the oil suction screen usually once a year. Lycoming recommends it every oil change according to their service instructions on how to change oil, but that seems excessive. Most mechanics I know don’t even know about the suction screen! Be sure to have a AN-900-16 gasket on hand for it.

https://www.lycoming.com/sites/defa...ervicing and Associated Corrective Action.pdf
 

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Yes, this is the answer! Its an intake manifold plenum, not part of the crankcase!!

You have solved my problem and Im feeling a little foolish. :eek: Yes, this is precisely what I have, the intake manifold plenum. So no oil in here... which makes perfect sense but just looking at it from the outside, it doesnt jump out and bite you (glad its not a rattler). Anyhow, thanks for showing me the obvious without also smacking me for not knowing any better. I have to admit one of my buddies came over while I was doing the oil change and remarked that those air intake pipes running through there was cooling the oil too... of course he has an airplane with a BMW motorcycle engine as the power plant! So I dont feel too bad! :)



Sounds like you have a horizontal induction engine with the throttle body pointing forward. If so, the oil sump is above the intake manifold plenum. In the 3" below the drain plug, there is just an air plenum (so no oil there). Does your sump look like the one below? If so, there's no oil below the drain plug.

View attachment 30450
 
Glad you got it figured out!

But, removing the oil screen is still important too. In the screenshot below from the Lyc parts catalog (you can download all these nowadays from Lyc), the screen is item 14, and it's held in place by the plug 19 and crush washer 18 (AN-900-16), which taltruda above called out. The rest of those parts on that diagram are only used for the AIO-series engines.

Not much oil comes out of that plug when removed, so a disposable coffee cup is plenty to catch what comes out.

Capture.JPG
 
Thank you for the view of the oil suction screen!

Hi Tom,

Thank you, I will be pulling the suction screen tomorrow! Thanks also for the Lycoming SB pertaining to the screen. Another gentleman helped me understand the intake manifold is directly under the crankcase and does not have oil in it (obviously)! lol The airplane does sit as if it is in level flight and now that I understand it is the intake manifold underneath the crankcase, I am now comfortable that I am getting a full oil drain when I open the oil drain valve at the port front bottom of the crankcase.

Learn something new every day and the folks like you and him, here on Vans AF are outstanding and immensely helpful to rookies suck as me! :eek:

Dan

Chock the mains, and raise the tail to level flight. You should also be pulling the oil suction screen usually once a year. Lycoming recommends it every oil change according to their service instructions on how to change oil, but that seems excessive. Most mechanics I know don’t even know about the suction screen! Be sure to have a AN-900-16 gasket on hand for it.

https://www.lycoming.com/sites/defa...ervicing and Associated Corrective Action.pdf
 
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Thank you again!

WILCO on the screen and THANK YOU so much for your assistance Mr Gerhardt!
:)

Glad you got it figured out!

But, removing the oil screen is still important too. In the screenshot below from the Lyc parts catalog (you can download all these nowadays from Lyc), the screen is item 14, and it's held in place by the plug 19 and crush washer 18 (AN-900-16), which taltruda above called out. The rest of those parts on that diagram are only used for the AIO-series engines.

Not much oil comes out of that plug when removed, so a disposable coffee cup is plenty to catch what comes out.

View attachment 30452
 
You have solved my problem and Im feeling a little foolish. :eek: ... So I dont feel too bad! :)

Please come back for any other questions - the people on VAF want you fly your aircraft safely. Every RV is different, and it's your mechanic's and your responsibility to maintain it correctly. Doing so will give you many years of enjoyable flying.

A quick tip to search VAF - just type something like this in the google:

site:vansairforce.com maintenance tips

site:vansairforce.com oil suction screen

site:vansairforce.com oil filter

site:vansairforce.com ignition timing

site:vansairforce.com nosewheel bearing

The google search often comes up with better links than the VAF search.
 
Please come back for any other questions - the people on VAF want you fly your aircraft safely. Every RV is different, and it's your mechanic's and your responsibility to maintain it correctly. Doing so will give you many years of enjoyable flying.

A quick tip to search VAF - just type something like this in the google:

site:vansairforce.com maintenance tips

site:vansairforce.com oil suction screen

site:vansairforce.com oil filter

site:vansairforce.com ignition timing

site:vansairforce.com nosewheel bearing

The google search often comes up with better links than the VAF search.

Just to add to this, using quotes will search for strings (phrases).

Example:

site:vansairforce.com oil filter - will search for instances of the word oil and instances of the word filter

site:vansairforce.com "oil filter" - will search for the phrase "oil filter"

You can combine quoted and non quoted as well.

site:vansairforce.com "oil filter" lycoming
 
Chock the mains, and raise the tail to level flight. You should also be pulling the oil suction screen usually once a year. Lycoming recommends it every oil change according to their service instructions on how to change oil, but that seems excessive. Most mechanics I know don’t even know about the suction screen! Be sure to have a AN-900-16 gasket on hand for it.

While many follow that, doing it on a new to you plane is a good idea. You never know what the last guy was doing. I know a guy that is struggling with fuel debris issues. It has been 6 years and the finger strainer in the servo had never been cleaned as he didn't know it was there. NEVER trust the "last guy."

Larry
 
...one of my buddies came over while I was doing the oil change...

Thank you, I will be pulling the suction screen tomorrow!

Perhaps too late. The screen draws oil from the bottom of the oil sump. It is removed for cleaning while the sump is drained.

Has someone at your airport showed you how to cut a filter for contents inspection?
 
Thank you for the Search Ideas

Hi Mickey, I appreciate this tip, I will put it to use for future issues... I didn't really understand how best to search this massive database of information from other experienced Vans builders/owners.
Dan

Please come back for any other questions - the people on VAF want you fly your aircraft safely. Every RV is different, and it's your mechanic's and your responsibility to maintain it correctly. Doing so will give you many years of enjoyable flying.

A quick tip to search VAF - just type something like this in the google:

site:vansairforce.com maintenance tips

site:vansairforce.com oil suction screen

site:vansairforce.com oil filter

site:vansairforce.com ignition timing

site:vansairforce.com nosewheel bearing

The google search often comes up with better links than the VAF search.
 
Already drained the oil but havent yet refilled the crankcase.

Hi Dan,

Yeah, I already drained the oil without knowing the screen should be pulled during the drain. Still I will pull it and check it. I haven't yet refilled the crankcase.

I do know about the process for cutting the filter to check it for metal, etc and will be doing that with my buddy. Appreciate you bringing it up though.

Best wishes and safe fun flights, whether getting somewhere or simply enjoying the beautiful experience of strapping our wings on and blasting off.

Dan

Perhaps too late. The screen draws oil from the bottom of the oil sump. It is removed for cleaning while the sump is drained.

Has someone at your airport showed you how to cut a filter for contents inspection?
 
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Amen, Larry. What I have learned from this experience of buying this bird is that clean log books don't necessarily equate to a well maintained airplane - in fact it is probably not the case. Although my bird is, in fact, a good bird, there have been many gigs I have had to trouble shoot, track down, find out about, and fix. After traveling about 1200 miles to the airplane, I bought it based on a couple of test flights and my own - lacking - inspection of the airplane, and some back and forth with the previous owner. Honestly I dont know if a pre-buy inspection would have uncovered all the little gigs (and a couple of bigger ones) I should have found someone at the location to do it... but it is such a pretty bird, well equipped and appointed and I was all in after flying her a couple of times. A pretty shiny object!

PS... I will also be looking for that finger strainer in the servo!

While many follow that, doing it on a new to you plane is a good idea. You never know what the last guy was doing. I know a guy that is struggling with fuel debris issues. It has been 6 years and the finger strainer in the servo had never been cleaned as he didn't know it was there. NEVER trust the "last guy."

Larry
 
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Nice Search ideas on a GREAT forum.

Thanks! I will put this to practice in future searches... as I hate creating a new issue when it has probably already been asked and answered by someone else. I have found the people on here to be amazing and so helpful - its a GREAT forum. :D

Just to add to this, using quotes will search for strings (phrases).

Example:

site:vansairforce.com oil filter - will search for instances of the word oil and instances of the word filter

site:vansairforce.com "oil filter" - will search for the phrase "oil filter"

You can combine quoted and non quoted as well.

site:vansairforce.com "oil filter" lycoming
 
Dan L,

The plates where the nose gear leg goes into the engine mount and form an upside down pyramid, seem to be designed to trap and collect oil, in particular oil from the screen. Consider covering the opening with aluminum foil, stuffing the opening with paper towel, or doing something else to keep the pyramid from collecting oil.

Regards,
 
I do not understand what the big aversion is to following the SB per manufacturer and examine the sump screen? A crush washer, a couple drips of oil to clean up and safety wire.... 10 min longer and it is done right. We religiously cut open the filter looking for dust, but ignore the big parts collector....?
 
Hi Larry,

No aversion, just didn't know it existed! lol Now that I know, it will get pulled and checked today. Just part of the learning experience as a new experimental owner. I feel just a bit smarter with the new knowledge. lol :D

Oh definitely know about cutting the filter and will do so.

I do not understand what the big aversion is to following the SB per manufacturer and examine the sump screen? A crush washer, a couple drips of oil to clean up and safety wire.... 10 min longer and it is done right. We religiously cut open the filter looking for dust, but ignore the big parts collector....?
 
Hi Dan,

I know that you are asking, my comments were for those who know the SB , but choose not to comply with it. I don't understand their reasoning.

I am sorry that I wrote it in such a way that you thought my comment was directed at you.
 
I agree with u Larry, about the screen. That’s why I mentioned it rather than him worrying about just draining the oil. If he had a question about draining oil I doubt he knew anything about the screen, as we have seen even old timers ignoring the screen.
 
I do not understand what the big aversion is to following the SB per manufacturer and examine the sump screen? A crush washer, a couple drips of oil to clean up and safety wire.... 10 min longer and it is done right. We religiously cut open the filter looking for dust, but ignore the big parts collector....?

Do you also follow their requirement that the engine NEVER be run LOP? Do you run EI with advances over 25*; Also a no no, according to the manual. Or maybe you pick and choose which guidance to follow better than the rest of us. Not suggesting that folks ignore it and I have no aversion to it and applaud the folks that do it every oil change. Just stated the fact that most people, including many aircraft mechanics, do it only at annual. As mentioned by others, some mechanics never do it.

I understand why the SB is out there, as you just never know when pieces are going to depart their origin components. Also, those that burn a lot of oil are wise to do it more often as carbon chunk large enough to block the screen are common in this case.

Larry
 
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Larry,

No offense taken.

I did not know about the prohibition for running LOP. Is this the same for injected vs carburetor?

My GRT EFIS and EIS really help in leaning very accurately, I normally run ROP to keep things cooler but I understand that running LOP saves fuel and in the ultra high prices we are suffering now... i can see why folks are interested. I suppose with the recently fleet wide approval for 100 UL, fouling problems will be decreased significantly?

Is running LOP not recommended due to getting exhaust valves overly heated?

Thanks

Dan

Hi Dan,

I know that you are asking, my comments were for those who know the SB , but choose not to comply with it. I don't understand their reasoning.

I am sorry that I wrote it in such a way that you thought my comment was directed at you.
 
Hi Keith,
Its getting pulled in about an hour and I appreciate you raising the flag on it. :)

I agree with u Larry, about the screen. That’s why I mentioned it rather than him worrying about just draining the oil. If he had a question about draining oil I doubt he knew anything about the screen, as we have seen even old timers ignoring the screen.
 
Larry,

No offense taken.

I did not know about the prohibition for running LOP. Is this the same for injected vs carburetor?

Dan

Most of us here run LOP in cruise. Lycoming has simply decided not to endorse it and stuck with the 60 year old guidance. I suspect liability is part of that in addition to the fact that several instruments as well as significant knowledge are required to do it safely. There is just no incentive for them to bother and likely incentives NOT to address it. They know we are doing it en mass and if there was a concern, I am confident that there would be an SB issued by now. Same with EI.

Larry
 
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My Opinion

So my opinion is that the Cessna 172 and 182 manual says to not run lean of peak. I think Lycoming is just going along with Cessna since their are so many of those certified planes out there and the lawyers would be all over them if the recommendations from the two are different. Also I think Cessna would need an STC to allow running lean of peak. JMHO

So in answer to the question, yes, we pick and choose the recommendations for experimentals, but we try and do it with science and math.

Just for fun, I think most of the modern cars run lean of peak on the highway to get better fuel economy. I believe this effort was first proven out with experimental planes. So we got that going for us…
 
I am certain you are right about liability, they got it certified way back when and they aren't about to go through another certification process and risk law suits. Cant hardly blame it in this litigious world we live in now.

Most of us here run LOP in cruise. Lycoming has simply decided not to endorse it and stuck with the 60 year old guidance. I suspect liability is part of that in addition to the fact that several instruments as well as significant knowledge are required to do it safely. There is just no incentive for them to bother and likely incentives NOT to address it. They know we are doing it en mass and if there was a concern, I am confident that there would be an SB issued by now. Same with EI.

Larry
 
I found a small piece of metal in the screen....

Hi Keith, Hgerhardt, Tom Altruda, Larry

So I pulled the screen, just getting the safety wire off was the biggest challenge due to the access being quite limited! Not quite sure yet, how I am going to effectively put that safety wire back on, perhaps you have a hint?

In looking at the debris inside of the screen, which was limited to about 6 total pieces, 5 of the 6 were organic in nature, in my opinion inconsequential. However, there was one small piece of metal which has me concerned. Since I am prepping for my condition inspection right now, I showed it to my A&P, we are going to stick a borescope in the hole in the crankcase where the screen goes and see what we see, we are also going to be cutting open the filter to see what we see, as well as do the standard compression test and borescope the cylinders to see what we might see. I am also sending in an Oil Sample to ALS.

Assuming we find nothing of concern through all of this, I am going to return the aircraft to service following the CI and continue to monitor.

Thoughts?
Dan

I agree with u Larry, about the screen. That’s why I mentioned it rather than him worrying about just draining the oil. If he had a question about draining oil I doubt he knew anything about the screen, as we have seen even old timers ignoring the screen.
 
You are right about that upside down pyramid on nose gear mount!

Roy,

Thanks!

That pyramid does capture oil dripping down from the filter extraction as well as the screen extraction. I did a better job using the cap from one of my window cleaner cans to catch the oil out of the screen hole. Upon inspecting the "pyramid" with my inspection mirror, I did notice it had collected a good amount of the oil which I didnt capture from the filter extraction so I cleaned it all out with the ubiquitous blue paper towels - they do a great job! Next time got to do a better job of capturing the significant amount of oil which is still in the filter during the extraction. I have it pretty well cleaned up but it is absolutely amazing how that oil gets EVERYWHERE and will be worse so at cruise speed!

Dan

Dan L,

The plates where the nose gear leg goes into the engine mount and form an upside down pyramid, seem to be designed to trap and collect oil, in particular oil from the screen. Consider covering the opening with aluminum foil, stuffing the opening with paper towel, or doing something else to keep the pyramid from collecting oil.

Regards,
 
Hi Keith, Hgerhardt, Tom Altruda, Larry

So I pulled the screen, just getting the safety wire off was the biggest challenge due to the access being quite limited! Not quite sure yet, how I am going to effectively put that safety wire back on, perhaps you have a hint?

In looking at the debris inside of the screen, which was limited to about 6 total pieces, 5 of the 6 were organic in nature, in my opinion inconsequential. However, there was one small piece of metal which has me concerned. Since I am prepping for my condition inspection right now, I showed it to my A&P, we are going to stick a borescope in the hole in the crankcase where the screen goes and see what we see, we are also going to be cutting open the filter to see what we see, as well as do the standard compression test and borescope the cylinders to see what we might see. I am also sending in an Oil Sample to ALS.

Assuming we find nothing of concern through all of this, I am going to return the aircraft to service following the CI and continue to monitor.

Thoughts?
Dan

Step one is to determine if the piece is aluminum or steel or something else. Sometimes a piece of casting flash comes off and no big deal. Sometimes it is something critical. If you determine the composition of the piece, Lyc can tell you the potential part(s) it came from. However, who has a mass spectrometer in their basement.

Larry
 
Hi Larry,

It is NOT magnetic, appears to be aluminum to me:
MetalChunk.jpeg

Here's the other stuff, also NOT magnetic, looks like organic materials:
OtherStuff.jpeg

Dan
 
Hi Larry,

It is NOT magnetic, appears to be aluminum to me:
View attachment 30533

Here's the other stuff, also NOT magnetic, looks like organic materials:
View attachment 30534

Dan

There are a whole bunch of aluminum parts with casting flash that can break off. Often when critical parts break off, at least one surface is machined flat or round. Can't really say don't worry about it, but encourage you to examine under magnification and look for signs of machined surfaces vs very rough surfaces.

Larry
 
Larry,

WILCO. Im also interested in seeing the inside of the engine with the bore scope. I know I wont be able to see everything everywhere but will get to look at key areas which could reveal more metal, or none. Im hoping just casting flash.

Thanks

Dan

There are a whole bunch of aluminum parts with casting flash that can break off. Often when critical parts break off, at least one surface is machined flat or round. Can't really say don't worry about it, but encourage you to examine under magnification and look for signs of machined surfaces vs very rough surfaces.

Larry
 
Larry,

WILCO. Im also interested in seeing the inside of the engine with the bore scope. I know I wont be able to see everything everywhere but will get to look at key areas which could reveal more metal, or none. Im hoping just casting flash.

Thanks

Dan

Quite unlikely you will get the borescope up in the engine from the strainer cavity,though I have never tried. The are only two small square openings that feed that strainer cavity from the rest of the sump and they require a sharp 90* turn to get something past them.

Larry
 
Borescope up the screen hole looks like this.. you can’t really see far..
 

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Aluminum Flashing

Hi Tom, Larry,

I concur, not going to help to look in the screen hole.

On further review with a magnet and 10x magnification, it appears to be simply a tiny piece of aluminum flashing.

Upon close inspection, Im not nearly as concerned as I.

Now to get that screen and plug back in... and then try to safety wire it... thats going to be a job for my A&P! :D

Thanks!

Dan
 
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