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Exhaust valve progression

scard

Well Known Member
Advertiser
Here is an exhaust valve progression we've been "watching" for about the last 100hrs.

Compression not up to snuff and the pre-flight elbow check verifies it each flight... About a year ago.


About a 3 months later after some more flying. This is the wishing / hoping phase :).


couple months later. Time for a look-see... The elbow (and actual) compression check says "uncle"! Yep, I see you.


A couple months later, today we went to the hangar to take one last look, knowing how the rest of the morning was going to be spent.



iphone image after removal.


Off to Sal's pizza parlor and cylinder repair. Compression test you ask? 35/80.
 
Wow, it looks like the valves are heading in the direction that was in a recent issue of AOPA.

Just one this way or do you have more getting ready to fail?

Looks like you have one of those 180 deg articulating bore scopes.

Bought one to find out why my compression had issues. Took it along with my RV to a local mechanic. He ended up wanting it...

Found out someone had installed the wrong length of intake pushrod. He saw this before removing the cylinder. Was so impressed he wanted to know where I bought it. After some horse trading (3-hours of labor) it was his.

Great tool for looking inside engines!

Best regards,
Mike Bauer
 
Scott,

Thanks for posting the pictures. Very interesting. Sorry it ended with a cylinder repair!

Dan,

Thanks for pointing out the rotation aspect. I missed that when I looked through them the first time! Your posts rarely disappoint!
 
These ECI cylinders eat exhaust valves like candy. We've gone around and around for the last 10yrs. They've all been off at least once. Old hat. Field Replaceable Unit.
 
These ECI cylinders eat exhaust valves like candy. We've gone around and around for the last 10yrs. They've all been off at least once. Old hat. Field Replaceable Unit.

Interesting. Would you happen to know if the seats are some other metal makeup or configuration that may be different than Lycoming?
 
These ECI cylinders eat exhaust valves like candy. We've gone around and around for the last 10yrs. They've all been off at least once. Old hat. Field Replaceable Unit.

After a recall on all cyl's on my Warrior in the late 90's. And then two (2) recalls back to back on my 6A.... all four again!!!!! twice. I am done with ECI.
 
What was the brand and model of borescope you were using?

The same $99 ebay from china articulating head usb camera that a bunch of us bought a little over a year ago. Taking a good look inside a cylinder should be child's play these days.
 
Folks, everyone is done with ECI. Continental bought the assets of Danbury Aerospace (which included ECI and sister brands) back in the summer of 2015. ECI is gone. The handwriting was on the wall as far back as 2012, when Danbury's owner and CEO passed away.

The purchase had two goals. They immediately ended production of PMA-Continental parts, as those parts sales competed with Continental's own OEM parts business. They kept the Lycoming PMA parts business (and by extension, the Titan line of clone engines built with them), because it had the potential to increase their market share in an otherwise shrinking market.

Continental renamed the Texas production facility "Continental San Antonio", but then announced plans to close it in late 2016. They've been steadily moving production elsewhere ever since. For example, PMA Lycoming cases, cranks, and camshafts come from the CMG plant at St Egidian, Germany, same place they build the diesels. That's good; it's a very high-tech shop. Titan-brand engine assembly is in Fairhope, Alabama, literally in the same room with CMG Mattituck overhaul assembly. Same new parts.

OEM Continental cylinders are machined and assembled in Mobile, but I have no idea where they are producing PMA Lycoming/Titan cylinders right now. There are a few former ECI guys in San Antonio who still work for Continental. CMG will break ground for a new, consolidated Mobile plant in the next month or two. When that comes online in early 2019, you can expect automated machining of a whole lot of stuff currently made by vendors.

True story. By the late 90's GM had made huge improvements in product quality, but the customers were still leaving. They hired J D Powers to survey and find out why. Should have saved their money, because the answer was obvious, at least in retrospect. The average car shopper's perception of 90's GM quality was based on their experience with an 80's model.

Continental and Lycoming are both in that position right now. To his great credit, Continental's Rhett Ross has been quoted as saying they must move into the 21st century, and has led the company in actually doing something about it. Will they be successful? I dunno, we'll see. In the meantime, let's quit hating ECI. Like Pan Am or Circuit City, it's history.
 
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Continental cylinders for Lycoming

I saw a set of Continential cylinders for a Lycoming and I was really impressed. The visual quality of cylinder was good, the pistons already had the rings installed and gapped and oriented in the cylinders. All you have to do is pull the pistons out of cylinders just enough to install the pins and then install cylinders.

Not too long ago, the rings Always had to be installed , gapped, removed, installed, oriented, compressed,blah blah Blah.... not sure if I completely trust this new way but it shows someone is listening on improving the process.
 
Scott,
I am curious why you did not pull the cylinder after the first or second photo? I'm 100% for watching conditions to gauge their severity; however, an exhaust valve is one of those things that can fail suddenly and catastrophically. I am not judging - just trying to learn. Also, do you have EGT CHT data and did that show the failure progressing?
 
Scott,
I am curious why you did not pull the cylinder after the first or second photo? I'm 100% for watching conditions to gauge their severity; however, an exhaust valve is one of those things that can fail suddenly and catastrophically. I am not judging - just trying to learn. Also, do you have EGT CHT data and did that show the failure progressing?

I guess all I can say is that we all have different risk tolerances. I like being able to observe the monster that lurks in full view.
 
The cylinder is back on and ready for a test flight this weekend. Not too shabby, AOG only one weekend.
While the #3 cylinder was away on vacation, I took the time to add bypass ducts to the #3 and #2 baffles. I can't wait to see the results of that.
 
Question because I really don't know...

When a valve like this eventually fails and deems the cylinder dead for power, will the engine make enough power for the airplane to maintain altitude and make it to an airport? Say 10 to 20 miles away? Would it be so rough that you'd have to reduce the power setting and land immediately?

** standard day, standard weight, normal 4 cyl RV, nothing catastrophic...
 
Usually an engine that ingests a valve is followed shortly by catastrophic failure, but nothing is certain. If just a little peice breaks off of the valve and it is your lucky day the piece just might go out the exhaust on the next cycle and you are left with a rough running engine that might get you to the airport you mention.
Bigger pieces than that will probably get beat around in the cylinder, potentially busting a piston or worse.
 
I ate a valve

Years ago I had a cessna 150 (continental o200). I was on my way down to houston from the DFW area and the engine began to shake. I pulled it back to idle... switched Left/Right Mags... didn't help. I was lucky that there was an airport just about 3 or 4 miles away and the C150 will glide pretty far too.

After we landed, oil was pouring out of the engine. The valve poked a hole in the piston.

I don't think a stuck valve is much better depending on how open it gets stuck. It can make for a pretty shaky engine. Another guy I know had a cherokee where the valve got stuck and it bent the push rod.

Scott... I'm glad you guys got it fixed so fast. I know it is a drag not having a spare airplane... but I think you are working on changing that. :)
 
Yeah the very first pic shows a green edge indicating very high temps, that I believe ought to be considered a stop sign.
Glad it didn?t come apart on you. How were the guides?
Tim Andres
 
The guide was clearly shot. The morning that we pulled the cylinder, you could clearly see the valve doing a side-step into the seat with the borescope as I rocked the prop open/closed. Now, That gave me the shivers :).

I was quite happy with the cylinder shop that it went to (Sal in Prosper Tx). Tanya shipped it on a Wednesday and we had it back the next Tuesday. She said Sal was easy to talk to as well. How about that! Compared to the last one that we sent to ECI, who had it for over a month until I told them that I'm coming tomorrow to pickup my cylinder repaired or not. Woohoo, my pushrods even fit upon reassembly.

Two little work sessions during the week to reinstall and get everything buttoned back up and it is back in the air. I did a couple short test flights over the field yesterday. Happy airplane. Solo, light on fuel, 80deg OAT. It felt like a rocket ship to the above pattern orbit. Oh, and the first early indications of the new baffle bypass ducts on #2 and #3 are very exciting too.

Now for a nugget for "internet fodder". "...indicating very high temps..."? Whether contributing or not, we didn't need an indicator to know that there were very high temps in these cylinders. We know for sure that there were, given a lightspeed ignition that failed to max advance (42deg) and was flown for at least a few flights before we figured it out. That event was probably about 40hrs before the first picture in this thread... However, this cylinder was already on it's way (exhaust leak) before that.
 
Good to hear that there was not heat damage to the seat or head. The extra heat can crack seats and heads.

Which one is next?:D
 
Vic is right!!! Do the right thing....

Just got done with a super thorough prebuy (now annual) and guess what got checked.... ALL the valves (everything around them too) and everything else we could see with one of those fancy 180 degree boroscopes!!! Boroscopes are so cheap these days it's a sin to just rely on the hiss out the exhaust pipe/low compression reading to see what is going on. Go get one, take a peek, if the valves etc look bad then spend a little money and save yourself a lot of frustration!!! Not a lot of owners like to break out the pocket book but thankfully you all that are here are much more inclined to R&R a cylinder etc... Vic is right, Vic is right and Vic is right if you want to know how I feel!!! Don't put your life in danger...
Best,
Brian
RV-71 in progress....
 
Scott: In your first post, you refer to an "elbow check". What is an elbow check?

A potentially, highly calibrated, instant reading, compression tester that the vast majority of us carry around with us at all times. Why not use it every time you go fly? Just use good practice and treat any touch of the prop as a loaded weapon. I choose to turn the prop backwards to get a general sense of compression.
 
Scott,

Thanks for the thread with photos. Very educational. I was inspired and bought a borescope yesterday. Waiting for it to arrive.

Maybe I missed it, but were there any other signs or symptoms indicating this exhaust value issue besides looking at them with a camera and seeing they were burnt?

Obviously ECI is no longer, what replacement parts are you using? Is it OK to mix and match different MFG stuff? Sorry for the ignorance.
 
Ok, I re-read. My apologies. Problem discovered through compression check and issue with light-speed ignition.. monitored by borescope. Got it.

Still one question please. Are you having the original ECI cylinder heads re-done or are you replacing them with new parts? I understand the valves and valve guides are garbage. Does that mean the cylinder head is done as well?

Again, sorry for the ignorance. Trying to understand.
 
EGT's?

Scott, What sort of EGTs and CHTs are you running on your engine normally? We have a few of these ECI cylinders and I'm interested in your experience with replacing valves. I had one set do 350 hours before the AD kicked in and the valve stems were stepped 2-2.5 thou. How many hours are you seeing before needing repair?
 
The same $99 ebay from china articulating head usb camera that a bunch of us bought a little over a year ago. Taking a good look inside a cylinder should be child's play these days.

Scott, could you post more details, or a link to a thread, perhaps. I'd like to buy one of these USB cameras, but want to make sure I get one that others have used and are happy with.

Thanks!
 
Exhaust valve

Scott,

Very interesting thread as I just discovered something similar on my YIO-360-M1B with 341 hours since new:

2r7pniq.jpg



This is the #4 Exhaust Valve and the compression test measured 76/80 :eek:
EGT's and CHT's are all normal :eek:

Guess the cylinder will have to be pulled :mad:

I recently bought a Vividia Ablescope VA-920 and am very happy with it.
 
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Borescope

Scott, could you post more details, or a link to a thread, perhaps. I'd like to buy one of these USB cameras, but want to make sure I get one that others have used and are happy with.

Thanks!

A good quality one is the ViVidia AbleScope VA-400. I see them on Amazon for 199.98 I got mine over a year ago and find that it works very well.

Here is a link to a great article on the AOPA web site on the "Anatomy of a valve failure" https://www.aopa.org/training-and-safety/air-safety-institute/valve-safety I printed out the Poster for a quick reference. With a bit of study and some practice it is not difficult to get a really good idea of the well being of your cylinders.

Scott, thanks for posting your pictures and findings. I have been using the above mentioned borescope for about a year now. As we travel far and wide in our RV's (and other less capable airplanes) it is of utmost importance that we keep our engines in tip top running order. For us to do that I believe a bore scope is possibly the most important tool in our tool box. Other things are important as well such as regular oil changes (max. 50 hrs) oil analysis, oil filter media examination and compression checks. If we do these things twice a year and promptly attend to any sign of trouble I believe that probability of a catastrophic engine failure while it is not ZERO it is very close. (Oh did I mention the need for fuel in the tank??)

One question I have for you Scott is, what kind of oil are you using in your engine?
 
Scott,

Very interesting thread as I just discovered something similar on my YIO-360-M1B with 341 hours since new:

2r7pniq.jpg



This is the #4 Exhaust Valve and the compression test measured 76/80 :eek:
EGT's and CHT's are all normal :eek:

Guess the cylinder will have to be pulled :mad:

I recently bought a Vividia Ablescope VA-920 and am very happy with it.

Wow! So glad we have access to cost effective borescopes these days! This is a very sick valve. This could have saved you a major issue or worse!

I am starting to think a quick look is smart at every oil change!

Love my VA-800 with wifi adapter!

s902975211958334_p280_i2_w800.png
 
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Cyl. Temps?

Wow! So glad we have access to cost effective borescopes these days! This is a very sick valve. This could have saved you a major issue or worse!

I am starting to think a quick look is smart at every oil change!

Love my VA-800 with wifi adapter!

s902975211958334_p280_i2_w800.png

Can you share with the group what kind of Cylinder head temps you are typically seeing? Also, ROP or LOP?
 
ECI O-320 Valves and Ops Info

I have a similar ECI engine to Scott's on my RV-9A. ~1900 hrs now. I have replaced one exh valve( in #1) at 1600 hours. It never looked bad with a scope, but it leaked(low compression with hissing) and had some erosion on the sealing surface(video in the thread above). I scope and compression check every 50 hours at oil change. I have posted many of my valve pics and yearly performance numbers on VAF(the goal is a longitudinal record, but very loose).

Other than the one valve that we replaced - we have always had comps in the high 70's(hot or cold). I run LOP all the time other than take-off and burn 90% mogas. My CHT's are in the 320 range during cruise.

ECI O-320, Hartzell, P-mags, Carb, Phillips X-C Oil 20W-50
 
Actually this information would be interesting to know from anyone posting here who have experienced burnt exhaust valves. The brand of oil used is also useful information.

After the initial run in we have never had CHT's above 380F.
Cruise CHT's are typically in the 300F - 320F range.
We run LOP all the time other than take-off /climb and use only Avgas 100LL and Aeroshell W100 Plus.

Mike Busch has a very interesting webinar on Exhaust Valve Failures:
https://www.youtube.com/watch?v=KOExs_PC0L8

And Boroscopy:
https://www.youtube.com/watch?v=7R-dAmv9VZk

I downloaded our engine data recording and looked for a slow rhythmic oscillation in the #4 EGT as explained in Mike's webinar but couldn't find anything.
So apart from the borescope inspection there was absolutely no other indication that the valve has a hot spot.
 
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