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Oil consumption just increased!!??

AndyRV7

Well Known Member
RV7 with O-375 Aerosport Power engine, 520 hours since new, oil & filter changes every 25 hours, no metal or debris ever found, stable mid-70's compression's since birth (through last November's annual). I've always had oil on the belly.

I'm going to annual in 2 weeks but was wondering what other people may have to offer before I get to the mechanic. I bought this plane with about 140 hours on it. 5 years ago. It was consuming about 3.5 quarts in 25 hours at the time. That crept up to 4.5, then maybe as high as 5.5, slowly over the past 5 years.

My problem is that over the last 6-7 hours, my oil use seems to have jumped up to around 10 quarts. The inside of my cowling is dry except for a thin coating of oil from underneath the oil quick drain to the exit of the cowling. It sure doesn't look like enough to indicate 5 extra quarts ran out in the last few hours. Also, there is an oil sheen around some areas of the back of the engine on the passengers side, particularly around the oil dip stick tube. My mechanic had reasons for these things (an o-ring on the quick drain, and a paper gasket on the dip stick tube.). Things that probably require attention at annual, but don't seem to me to be significant enough to account for the high oil loss I think I am experiencing.

Just one last thought. I recently flew off the last hour of my 25 hour oil change interval. Before doing this, I topped off the oil to 8 quarts and when I landed (still hot) I was at about 6.5 quarts. Not exactly a scientific test but lower than the level I was hoping to see. For full disclosure, I usually fly the plane at 6 quarts and top it off when it gets down to 5.5 quarts. That is, unless I am going on a longer trip than local flying, at which point I would fill it to 7 quarts. I've never been alarmed by a low level of oil after I've landed. But I also don't have a historical sense of how the engine behaves when flown at 8 quarts.

Has anyone had similar experience at any point?? Any thoughts??

Thanks! Andy
 
The four-cylinder Lycs in our application generally quickly throw out anything above 6 quarts, so if your increase in consumption came coincidently with running it at 8, I’d think that there’s your problem. Get a better baseline by running it at no more than six, and see how many hours you get before adding a quart, then do that again and see if it stable...and a better number.
 
I was worried about that too but I think I've run out of time. I'm not going to fly the plane again until I take it to annual.

BUT...I never fly the plane at 8 quarts. When I noticed this issue around 6-7 hours ago I was flying with the oil around 6 quarts as I have done consistently since I've owned the plane. The thing that alarmed me was how low the oil was after a 4 hour day of flying.
 
go look at the Anti Splat Aero website and the ASA oil separator with the crankcase vacuum kit. Lots of good feedback on reducing oil consumption and clean up on the belly side of the fuselage.
 
1 qt in five hours is quite a bit. 6 quarts is a bit much for a 320/360 in my opinion (I run between 4 and 5 in my 320), but don't think that would account for that high of a burn rate, especially given that you have seen the consumption slowly rise with a consistent fill height. What you have is not normal (my opinion is that 1 qt in 10 hours is the end of the normal range, though not necessarily a problem when above that) and getting to a point that you will soon need to deal with it.

10 quarts in 25 hours is crazy high. If you can't rule out a leak, you likely have an issue with one or some of your rings or you are severly wearing one or several cylinder walls down past that cross hatch. A compression test may help identify a compression ring issue, but won't help identifying an oil ring issue or worn cyl walls( at least not until signficant wear). At some point, the burn rate will be high enough that you risk dropping below the minimum level (around 1 qt.) during a long flight.

The sudden onset would point to a broken oil ring or a leak you haven't identified. The sudden onset would make me concerned about continued flying with it untill the issue is found, in case it is not a broken oil ring (which is not a safety issue in itself). At the 1 qt / 2.5 hr burn rate, if the issue is in one cylinder I would expect to find wet plugs after a couple minutes of idling.

sorry, but you cannot address this type of burn rate with a lower fill level or air oil separator.

If the belly is relatively clean, you likely have a ring/wall wear issue or broken oil ring. If the belly is filthy, you likely have a broken compression ring or other issue causing severe blowby. Assuming broken rind due to the sudden and rapid acceleration of the burn rate.

I don't have enough experience to know whether a valve guide issue could produce this high of a burn rate. Maybe others could chime in. Valve guide issues would fall into the clean belly category.

Larry
 
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Thanks Larry. I too thought cylinder problem and pressure in the crank case (rings or valve guide). But these are just some rational ideas. I have no history of experience so I figured I'd find out what other people thought. My mechanic had me a little worried that they may not be able to identify a cause. And then I would have to out an oil separator on it to see if I am burning the oil or losing it overboard. None of these options sounds pleasant. Either way, I have a .4 hr flight to my mechanic. That is the only other airtime I plan on.

Thanks for the update Larry. I didn't mean to suggest any of these things would solve the issue. I know something is wrong inside the engine to cause the change. Let's see what my mechanic discovers.
 
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One other thought for you Andy. I originally had Cerminil cylinders (circa 2004) on my RV-8 engine. It never did much better than a quart in six hours, and then at about 1400 hours total time, the oil consumption just went through the roof - flew it from Houston to Dallas and put a quart in when I got there. I pulled the jugs and found that the rings had delaminates - at the time, ECI used a very hard coating on the ring/cylinder surface (because Cerminil was really hard), and that surface coating was flaking off, causing a lot of blow-by. They new about the problem, but customers only found out when they asked them - not the best in communication. That engine was built by Mattituck from an ECI kit.

Anyway, that might be something to check, and a potential for a significant increase in oil usage.

Paul
 
Thanks Paul. I remember when I was looking for a plane there was a particular cylinder brand that had some hair on them in the communities. ECI Titan maybe?? My mentor at the time eased my concerns. I don't remember much more but those discussions popped back into my mind when this happened. :eek:

I'll report back after my plane gets into annual in November. Hoping for the best!!
 
Have you pulled the plugs to see if any are wet?
Also, is the oil getting dirty really quickly, meaning black looking?

Vic
 
Data Point

I have an IO-375 in my RV-7 with ECI "Nickel Bore" cylinders ( I think this is the same thing as the "Cerminil" cylinders). Oil consumption since new was always around 6 hours/qt - not bad but not great. I am at 500 hrs now and consumption has increased to around 4-5 hrs/qt. I always run between 5 and 6 qts in it. Compression has always been great (78+) and absolutely no fouling on plugs.
 
I pulled the jugs and found that the rings had delaminates - at the time, ECI used a very hard coating on the ring/cylinder surface (because Cerminil was really hard), and that surface coating was flaking off, causing a lot of blow-by. They new about the problem, but customers only found out when they asked them - not the best in communication.

Paul, did they do anything about this for you?
 
I have an IO-375 in my RV-7 with ECI "Nickel Bore" cylinders ( I think this is the same thing as the "Cerminil" cylinders). Oil consumption since new was always around 6 hours/qt - not bad but not great. I am at 500 hrs now and consumption has increased to around 4-5 hrs/qt. I always run between 5 and 6 qts in it. Compression has always been great (78+) and absolutely no fouling on plugs.

Thanks Dan. I was probably about 5-6 quarts before the spike. So close to what you are experiencing, maybe a little higher. I will probably call Aerosport tomorrow for some information and advice too. Can't hurt to be able to tell my mechanic what they had to offer.
 
I have not pulled the plugs. My oil is jet black though.

Jet black oil is a sure sign of blowby. Compressions willl still show good due to the oil in the cylinders.
Do a thorough inspection with a borescope and check for any signs of scoring on the cylinder walls from potentially broken rings.

As I write this I don't remember how many hours you have on the engine. It may just be time for a top OH.

Vic
 
Jet black oil is a sure sign of blowby. Compressions willl still show good due to the oil in the cylinders.
Do a thorough inspection with a borescope and check for any signs of scoring on the cylinder walls from potentially broken rings.

As I write this I don't remember how many hours you have on the engine. It may just be time for a top OH.

Vic

Thanks Vic. 520 hours. Looks like this is going to be a very expensive annual.:(
 
Oil consumption

I?ll add this to to mix. Had a Mooney 201 customer (IO-360-A3B6D 500 hrs smoh) who had a increase in oil consumption similar to the beginning of this post. In addition the oil was very black and belly would accumulate a dry black sooty trail. Engine ran good, had great compression, nothing in the filter or screen, cylinders looked good with boroscope. The plugs were a little darker than normal with #3 being just a tiny tiny bit darker/wetter than the others. He was reluctant to dig deeper without a definite cause and flew about 50 more hrs with no change. Annual came due so put my foot down(Leverage) and pulled cylinders for a look. Everything looked really good and measured out within specs except #3 cyl mid barrel was severely out of round. Owner eventually told me right before this all started he had a high CHT on climbout, (only probe is in #3 cyl) he returned to the airport and found a large bird nest on top of #3 cylinder. A replacement cylinder was the fix and since they were off sent the other 3 cylinders to OH shop for inspection and rework as necessary. They were mostly good but valves got re-seated and barrels honed. Put it all back together with new rings, seals and gaskets plus a new engine monitor and engine all good again. Not exactly a top OH, but appropriate for a 500 hr engine.

Don Broussard A&P, IA, ATP
RV9 Rebuild in Progress
57 Pacer
 
Don, I am afraid to ask, but what did that job cost??

You can get a new cylinder for $1000 and overhauls are a good bit less than that. A scenario like Don mentions is what I am expecting (one cylinder has a cracked ring or heavily worn cylinder wall) and therefore you can probably get by with overhauling one cylinder. Though you oil consumption will go back to where it was in the recent past with that approach.

You or a knowledgeable buddy should be able to replace a cylinder in a day or two's work, including all of the baffling removal / replacement. I glazed two cylinders on my 6 during break in. I had them off, honed and replaced in two days.

I still feel that the sudden onset of the very high burn rate points to a broken ring, though Don's scenario of the birds nest is a good example of other problems that could cause very rapid cyl wall wear. The sudden onset points to one cylinder being the major problem and you need to take some steps to figure out which one it is. Easiest first step is to compare the plugs.

Larry
 
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Sounds like glazed cylinders to me. A good mechanic should be able to pull the cylinders, clean them up with a ball hone, and install new rings.
 
Just an update on the engine issue. My mechanic says there is nothing wrong with my cylinders or rings. He looked at all of them through the spark-plug holes and see no scoring or damage. He didn't bother to scope them because he said it would not show anything different.

They did a windage test and said every cylinder was high once they extrapolated back from a comparable Continental engine.

All compressions were good.

He says the engine was not broken in properly and it never established a good seal between the rings and cylinders and there is no way to remedy that now. If I remember correctly, he said something that sounded like there was some amount of oil pooling, I believe in the cylinders???

No metal in the filter or screen (as usual).

He gave me 2 options. Option 1: Try an air/oil separator to see if it brings down the high consumption. It wouldn't fix the problem but he said it was the cheaper option and what he would try before Option 2. Option 2 is to remove all cylinders and pistons and send them out for overhaul, and then "start from the beginning" by breaking them in properly.

I told him to add the air/oil separator and see if that gets my consumption back to tolerable levels. If the plane is unable to be flown without risking dipping into a level below the minimum 4 quarts, then I would guess Option 2 is all that is left. I guess all we are doing with option 1 is trying to get some more flight time on the original cylinders before we have to plunk down $5K to overhaul them.

To be honest, I'm not really comfortable with Option 1 but if it proves to lower and make my oil consumption steady, I guess I can get used to it.

Any opinions?? Thanks! Andy
 
JHe didn't bother to scope them because he said it would not show anything different.

If you paid him for that opinion without getting a borescope put in the engine, then you need a new mechanic.

And Option 1 is only delaying Option 2, if it's correctly diagnosed.
 
The one thing the mechanic could not explain is why an engine that may not have been broken in appropriately would suddenly experience a significant level of oil consumption.

A presume that you are saying that an inspection through the plug hole would be unable to determine if there isn't some other cylinder problem/damage, which is out of sight??

Will a bore scope provide all the diagnostics needed to find THE problem? Is there much more expense/knowledge to be found by pulling the cylinders off?

All I can do is take his advice at this point.
 
The one thing the mechanic could not explain is why an engine that may not have been broken in appropriately would suddenly experience a significant level of oil consumption. thats because he is not properly understanding what the engine is trying to tell you/him. It is speaking to you, it?s telling you something has drastically changed in recent hours and you should not ignore it. I recommend you listen to your engine and tell your mechanic or maybe a new mechanic to start pulling cylinders. It?s got some stuck, broken or delaminating rings.

A presume that you are saying that an inspection through the plug hole would be unable to determine if there isn't some other cylinder problem/damage, which is out of sight??

Will a bore scope provide all the diagnostics needed to find THE problem? Is there much more expense/knowledge to be found by pulling the cylinders off? yes

All I can do is take his advice at this point.
I think you should go with your gut, you know what it?s telling you, 3 quarts in 25 hours up to 10 in 25 hours, listen to your engine and your gut, get a new mechanic or slap this one up side the head.
 
He says the engine was not broken in properly and it never established a good seal between the rings and cylinders and there is no way to remedy that now. If I remember correctly, he said something that sounded like there was some amount of oil pooling, I believe in the cylinders???

Sorry, but I don't buy that. While high oil consumption is common when someone glazes their cylinders during break in, it doesn't explain the sudden, rapid rise in oil consumption at 600 hours. If that were the case, it would have been consuming at that rate from day one. Suggest you seek a second opinion. Though I do agree that the best course is to pull the cylinders for inspection / overhaul. IMO, a separator at 1 qt in 2.5 hours is not the right answer.

Still think you need to ascertain whether you are blowing oil out the breather or burning it, as that will better tell you what the issue might be. Either way, the path to reduced consumption is overhauling all or some of the cylinders. It is quite possible that a hone and re-ring vs. overhaul will be enough to solve the issue. A set of rings is under $100 and you can buy a ball hone for under $50 or rent an old school spring hone from the auto parts store for free. This assumes steel barrels, vs cermanil or chrome.

I honed and re-ringed at 100 hours. Took two days. Not a huge project.

Remember, compression tests tell nothing about the oil ring issues, delaminated rings (in the case of coated rings) or heavy cyl wall wear, all of which cause high oil consumption. A borescope will show cyl wall wear. Your mechanic is incorrect here. a borescope will show wall wear even when the compression test is showing 78.

Larry
 
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I have decided if I ever own another airplane with ECI/Titan cylinders they are getting removed ASAP and replaced by new Lycoming steel ot Superior through-hardend steel cylinder assemblies. I just went through the heartache of what ECI/Titan cylinders sluffing off the nickle coating can do to an engine in less than 250 hours SNEW; a $14K complete teardown and IRAN including new cylinder assemblies, ground crank and crankcase overhaul (fretting). Zero assistance from Titan. Lesson learned. Never again.
 
I just went through the heartache of what ECI/Titan cylinders sluffing off the nickle coating can do to an engine in less than 250 hours SNEW

I was leery about them too before purchase.

I spoke with Aero Sport last night and they came to the same general conclusions. The cylinders need some level of service. But even after their second opinion, I still feel like I don't have an answer. Why hasn't any metal been found!? and WHY has the consumption spiked!? There has to be some change that caused the spike, and there should be some evidence of the change.

I have the mechanic on hold for the moment. I was never a fan of the air/oil separator in the first place. But spending a lot of money to repair or replace the top-end seems like a casting net approach to a problem as well. Let's replace everything that could be causing a poor oil seal and hope the problem goes away. But what if there IS an inherent problem with the coating on the rings and cylinders. Then, I've just dropped a lot of cash and am likely to end up right back in the same place as I am now, sometime down the road.

I feel like I should just bring the plane home and take my time figuring this out.
 
I agree with what others have said. I am an auto mechanic by trade. Oil consumption does not just spike like that without a reason. You need to find a new mechanic. A borescope might show something and that is the place to start. You are more than likely going to have to pull cylinders and see whats going on.
 
borescope

Borescopes are cheap - just buy one and have a look.

https://www.amazon.com/s?k=borescope+wifi

61yOMl233KL._AC_SL1000_.jpg
 
I spoke with Aero Sport last night and they came to the same general conclusions. The cylinders need some level of service. But even after their second opinion, I still feel like I don't have an answer. Why hasn't any metal been found!? and WHY has the consumption spiked!? There has to be some change that caused the spike, and there should be some evidence of the change.

I can assure you there is evidence somewhere, but not all problems result in metal in the oil. A broken ring can cause an immediate spike. I have no experience with coated rings, but several here have indicated the delamination and resultant increased oil consumption is immediate. Very small amount of metal you would likely never see (large flakes that would fall out of suspension and sit on bottom of pan). I would guess that cyl wall coating delamination "might" show metal, but just don't know.

The why is not highly relevant. Whatever it is highly likely to be related to the rings/wall. The jugs need to come off and that will tell the tale. The likelihood of this being anywhere but the cyl assembly is quite remote. You can then decide on the remediation plan.

Larry
 
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I had a broken oil ring in several pieces in Radial engine. Only indication was a spike in oil consumption. Compression was 78/80 and borescope did not show any issues on cylinder walls.

Your oil consumption is telling you something.
 
Additional information

Spoke with the mechanic again and discussed my concerns. Mainly that if in fact I choose to rebuild the top-end, I am concerned with simply putting back the same equipment that "failed." That is, the Cermanil cylinders and rings I have in there now.

I asked about the fact that he couldn't identify the change in the engine that caused the spike in consumption. He said that there really was no other way the oil could have escaped because the exhaust and lower plugs didn't indicate it was burning. So aside from an engine seal or case plug not working, it would have to pass the rings.

He indicated that the pooling oil in the cylinders is indicating that the intake valve seat is probably the source but that would be looked at during the reman.

Does this change anything we have discussed? What would you guys thing my cylinder options are if I don't want to just start over" with re-manufactured Cermanil coated cylinders and rings?

To be honest, I can take back the plane and pull all the cylinders, or ask him to do it but does it really offer any additional information at this point? Other than maybe seeing of I have a delamination or broken ring someplace??

I'm just trying to make the most educated stab at fixing this problem. Thanks!! Andy
 
Spoke with the mechanic again and discussed my concerns. Mainly that if in fact I choose to rebuild the top-end, I am concerned with simply putting back the same equipment that "failed." That is, the Cermanil cylinders and rings I have in there now.

I asked about the fact that he couldn't identify the change in the engine that caused the spike in consumption. He said that there really was no other way the oil could have escaped because the exhaust and lower plugs didn't indicate it was burning. So aside from an engine seal or case plug not working, it would have to pass the rings.

He indicated that the pooling oil in the cylinders is indicating that the intake valve seat is probably the source but that would be looked at during the reman.

Does this change anything we have discussed? What would you guys thing my cylinder options are if I don't want to just start over" with re-manufactured Cermanil coated cylinders and rings?

To be honest, I can take back the plane and pull all the cylinders, or ask him to do it but does it really offer any additional information at this point? Other than maybe seeing of I have a delamination or broken ring someplace??

I'm just trying to make the most educated stab at fixing this problem. Thanks!! Andy

When the oil is leaving due to a wall ring interface issue, such as delamination of the wall or ring coating or a broken oil ring, it it leaving via burning. The bad interface allows excess oil to remain on the walls and this oil is burned during the power stroke, as well as to pool near the piston at rest. When the oil is leaving via blowby, such as from a broken compression ring(s) or out of round wear, it is leaving via the breather in tiny droplets and there will be no evidence of pooled oil or oil burning in the cylinders. This is not likely with 78/80 compression readings.

a bad valve guide "could" leave pooled oil, but unlikely to occur rapidly. You would see wet oil on the stem and upper head of an intake valve if it were bad enough to cause pooling. A bad exhaust valve guide would show large chunks of black crud on the stem / upper head if it was leaking enough to cause pooling. Both of these can be investigated without removing the cylinders.

Pooled oil points directly to a ring / wall issue. Again, suggest you pull the cylinders and examine. You can then decide if the valves need to be addressed or the rings. Maybe hone/re-ring, maybe total overhaul. You simply don't have enough data yet to make any decisions, the jugs need to come off. ou may be able to hone / re-ring and you may have to replace the cylinder and you may have to have new guides installed. You simply won't know until the jugs come off.

Anyway you cut it, the jugs have to come off, regardless of the cause. WHy rush the remediation decision until you examine the jugs and see what options are available, based upon the failure mode. If rings delaminated, you should be able to hone/re-ring at a low cost. Assuming you are not getting creamed with labor charges, this may be the way to go even if they fail again in 600 hours. If paying a lot of labor, may be wise to bite the bulllet and switch. Not entiirely sure you can hone these as I have no experience with cermanil. I know that nickel can be honed with special stones. Given the problems the previous poster mentioned about cermanil coming off and trashing his engine maybe should push you to swap to steel. Tough choices.


Larry
 
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This makes a lot of sense Larry. Thanks for taking the time.

I guess my mechanic just doesn't want to get any deeper into this thing. Twice he's reminded me I could simply take the plane back. And I absolutely would. But once I open the engine, I am not sure I would want to be the one that puts it back together.

Let me absorb this a little while. It seems that I have a bit of conflict in my symptoms. I may just be at the point where I need to contact an engine facility.


Happy Thanksgiving!!
 
The old submarine nuclear power answer is do it right even if it is hard, even if it sucks. The joke that goes with that is "if it isn't hard you aren't doing it right". The lawyers say "what's the worst that can happen? Get that accepted then you won't have more worry".

Taking it apart to inspect the rings is the hard answer. There are plenty of shops that will do that for you cheerfully if you don't want to do it yourself. Ferry the plane over and get a good look at it; it sucks and it's hard but it's okay. Better to know and not risk your safety or get stranded with it.
 
Sometimes a short answer can come across as shooting from the hip. When I stated that I would immediately replace any ECI/Titan Cermanil cylinders from 10 to 15 years ago in my previous post it was not a quck shotgun staement but one derived from personal pain.

So here is another short answer well thought out and reasoned. I would pull the cylinders. It's not that big a job for an experienced hand. I had similar quandries as you with a functional engine with black oil and high consumption with the ECI/Titan cylinders. Compression leak check showed #1 blowby into the case with air escaping the breather/oil filler (rings), rather than the exhaust (valves). I danced around the right decision until I put a digital camera scope in #1 and saw ugly cermanil coating delaminating. So I gave in and pulled that cylinder under supervision. It was eye opening to say the least. Further investigation found that I had cylinder serial numbers deemed un-airworthy by AD that ECI took back and reworked as a fix rather than replacing. ECI was famous for reworking and tagging cylinders on EAB aircraft engines that were supposed to be discarded on type certified aircraft by the AD. A big red flag.

My decision to tear down the engine wasn't an impulse. It was well thought out and considered. If all my cylinders hadn't had the un-reworkable ECI serial numbers I probably would have had the cylinders overhauled, but after the AD research and seeing what was going on inside the top end with the plating coming off I went for all new cylinder assemblies as per my previous post. And I felt I had no choice but to do a full teardown IRAN after seeing the marks where the plating material worked through the rings into the bottom end. That last sentence is where I could have saved a lot of work, frustration, money and safety by replacing the cylinders before they caused engine damage.

Granted I spent $14K for the whole enchilada with one of the most reputable and famous specialty engine shops with a 6 month waiting list just to get in, where they dyno break in the engine and the cosmetics and results are stunning. This included governor overhaul, prop flush, Pmag service and updates, and custom paint and valve covers. I probably could have done a basic field IRAN with new cylinder assemblies for $2K or $3K less. And the accessory work and prop and oil cooler flush could have been avoided all together had the cerminil metal coating not gone through the oil system if I had replaced cylinders before all this went down. Probably would have been half as expensive.

Check your cylinder serial numbers against the ECI AD. You may not want them. There is a real reason for the AD on ECI cylinders. And any rework done by ECI in the past for experimental aircraft with AD applicable cylinders was the wrong thing for them to do. If the serial numbers are hit by the AD get rid of some ticking time bombs before one goes off. That's what I didn't know and I am just trying to help someone else before their engine gets damaged $$$ or something worse. Spend some money now, rather than a lot between now and who knows when. Remember my engine only had 250 hrs on it since new. We're all in this together and I'm pulling for you.

Jim
 
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I am in the middle of something like this right now. O-360 A1A /original nitrided cyls., 20 years and 1500 hrs TTSN. Over the years it slowly went from about a quart in 10 hours down to one in 6, but recently dropped to one in 3. Compressions all good -- "too good" according to the engine guy at Premier, indicating oil getting past the rings. Also oil on the bottom plugs.

I looked with a borescope but I'm not experienced enough to know what I'm seeing so I got a local mechanic and he diagnosed it as rash (corrosion) on the cylinder walls . So I went ahead and pulled them and sure enough, areas of shallow pitting on all of them.

I considered new cylinders but decided to take them over to Premier Engines in Troutdale OR, and Jim there re-honed the walls and put new rings on for 1/4 the price of new. Now they're sitting on my workbench, to be reattached tomorrow. Hoping for the best!

PS. I watched / read some scary Mike Busch webinars / articles abut cylinder replacement -- kind of alarmist but probably worth doing to make sure you know what to be careful about. I pulled the cyls myself but will be getting A&P help putting them back on.

PPS. That Depstech borescope that rv8ch posted doesn't look ideal for cylinder work unless the head itself articulates? Need to be able to turn back 180 degrees right at the head to see everything. The Vividia ones for $199 or $399 do have that capability.
 
PS. I watched / read some scary Mike Busch webinars / articles abut cylinder replacement -- kind of alarmist but probably worth doing to make sure you know what to be careful about.

Are you saying his webinars are bad? I'm watching some now. Just want to make sure I'm not getting bad advice. I don't have any idea who Mike Busch is!

I too bought a borescope and hope to get my plane back tomorrow. Going to take my time with this. My biggest concern now is even if I bite the bullet and pay for a rehab of my top-end, I afraid to try to break the cylinders in. I read some horror stories about others who have done this and couldn't get the cermanil cylinders broken in properly, even the second time!

I think you'll make out well with yours. If I remember correctly, nitride coatings are to harden the steel cylinder. So you should have a pretty normal cylinder to break-in. Good luck with it. I don't have a mechanic on the field so I am going to proceed cautiously. If I take off a cylinder, I have to be able to put it back on.:(

What special tools did you need? I've seen some bent wrenches to add/remove the cylinders. Also, a ring compressor to get the piston back in the cylinder.
 
Are you saying his webinars are bad? I'm watching some now. Just want to make sure I'm not getting bad advice. I don't have any idea who Mike Busch is!

I initially liked some of Mike's early writing on maintenance. I have never talked to Mike personally. Just his underlings. His company basically preys on fear and perpetuates the myth that aircraft mechanics, on the whole, are shady at a minimum and flat out incompetent and dishonest at the worst. If you ever get a chance talk to some reputable honest shops who have been on the receiving end of Savvy's alledged experts armchair quarterbacking maintenance without being present and physically looking at the airplane or parts thereof. Savvy's service experts flat out tell mechanics to replace things that are easily repaired in the field, while at the same time completely missing major recurring inspections on the same airframe. I know of one Cirrus customer who pulled the plug on Savvy after wising up. Just my opinion based on direct experience. I do hope that Savvy has come around with better staff but my shop refuses to play their fear mongering remote micromanagement system game.
 
I initially liked some of Mike's early writing on maintenance. I have never talked to Mike personally. Just his underlings. His company basically preys on fear and perpetuates the myth that aircraft mechanics, on the whole, are shady at a minimum and flat out incompetent and dishonest at the worst. If you ever get a chance talk to some reputable honest shops who have been on the receiving end of Savvy's alledged experts armchair quarterbacking maintenance without being present and physically looking at the airplane or parts thereof. Savvy's service experts flat out tell mechanics to replace things that are easily repaired in the field, while at the same time completely missing major recurring inspections on the same airframe. I know of one Cirrus customer who pulled the plug on Savvy after wising up. Just my opinion based on direct experience. I do hope that Savvy has come around with better staff but my shop refuses to play their fear mongering remote micromanagement system game.

Interesting. Thanks.Been trying to keep to the factual like what the rings on the piston do and how to actually diagnose a problem, and then make my own judgement. Well see how it goes...;)
 
I have read all of Mike's books. I have operated and been responsible to oversee maintenance several high performance piston powered singles, twins, and turbo props.
I think what he says make a lot of sense. I have not had any direct dealings with him or his staff however I am not surprised that a lot of mechanics don't care for him. A lot of his thoughts are based on data and airline type maintenance and failure rates. I would recommend reading his latest book and make your own judgement.
 
What special tools did you need? I've seen some bent wrenches to add/remove the cylinders. Also, a ring compressor to get the piston back in the cylinder.

You will need special cylinder wrenches to get the jugs off. Different types for narrow vs wide deck. You don't need a special aviation ring compressor. I use a std automotive style and put the pistons in before installation on the case. You can also modify the compressor to do it the traditional way. Just drill out the rivets and replace with #6 screws/nuts.

Larry
 
Are you saying his webinars are bad? I'm watching some now. Just want to make sure I'm not getting bad advice. I don't have any idea who Mike Busch is!

I too bought a borescope and hope to get my plane back tomorrow. Going to take my time with this. My biggest concern now is even if I bite the bullet and pay for a rehab of my top-end, I afraid to try to break the cylinders in. I read some horror stories about others who have done this and couldn't get the cermanil cylinders broken in properly, even the second time!

I think you'll make out well with yours. If I remember correctly, nitride coatings are to harden the steel cylinder. So you should have a pretty normal cylinder to break-in. Good luck with it. I don't have a mechanic on the field so I am going to proceed cautiously. If I take off a cylinder, I have to be able to put it back on.:(

What special tools did you need? I've seen some bent wrenches to add/remove the cylinders. Also, a ring compressor to get the piston back in the cylinder.

Hi Andy - a couple of thoughts:

I personally gave up on the Cerminil after just not getting good break-ins. I really wanted the coating because I lived on the gulf coast at the time, and figured the corrosion protection was important. Well it turned out ai Flew the airplane five days a week, so static corrosion just wasn?t a problem! Nitrided barrels break in easily and consistently, if you follow proper procedure.

And while I totally appreciate any experimental owner/builder/pilot doing there own work, and learning in the process, I think that with something as major as pulling all four jugs you?d be best off finding another experienced owner to help you weigh it the first time. Even an A&P isn?t allowed to do work (solo) that they haven?t done before (with someone watching over their shoulder), and doing an entire Lycoming top end without ever having seen it done...well....there are a bunch of little things that can mess you up. These are simple engines, but there are different flavors of simple!

To be blunt, you aren?t going to learn what you need by reading posts on the ?net.

You don't need to find an A&P - find another experienced builder! There are about 25,000 people that read VAF, and at least a few of those probably live near you. Get some help, learn, and then help someone else in the future.

Paul
 
Are you saying his webinars are bad? I'm watching some now. Just want to make sure I'm not getting bad advice. I don't have any idea who Mike Busch is!

I'm in no position to judge Mike Busch or whether he's right or wrong about stuff, I just know he's an engine guy who writes a lot of articles in AOPA pilot, on AVWEB, etc. Since I'm a novice when it comes to engines I find them useful if sometimes a bit scary - making.

My use of "alarmist" was probably a poor choice of words. "Cautionary" would have been a better term -- I only mean that he preaches the pitfalls of pulling & reinstalling cylinders without following (or making sure your mechanic follows) Lycoming's instructions to the letter, and to not do so unless you absolutely have to. Which I would / will do in any case but especially after reading his various cautionary tales.
 
I afraid to try to break the cylinders in. I read some horror stories about others who have done this and couldn't get the cermanil cylinders broken in properly, even the second time!

I don't have that issue since mine are nitrided as you say. I'm actually quite looking forward to the break-in, it's not every day I have an excuse to say fuel economy be damned and fly around for hours down low at high throttle settings!

I don't have a mechanic on the field so I am going to proceed cautiously. If I take off a cylinder, I have to be able to put it back on.:
I'll be working on that today with the A&P. He's from another field but not far so it works out. After some conversations with him and also the guy who serviced the cylinders, and reading the instructions on the Lycoming overhaul manual, I feel like I would have a bit more confidence now that I could do this one on my own. But since he's around I'd rather be safe than sorry.

What special tools did you need? I've seen some bent wrenches to add/remove the cylinders. Also, a ring compressor to get the piston back in the cylinder.

Yes those are the main ones. A piston pin removal tool too, probably. Also those short intake pipes where they go into the sump were loose; I was able to borrow a 1 3/4" swager which fixed them right up.
 
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Update: I just reinstalled my cyls with the help of an A&P. I would definitely echo others' recommendation to get help from someone who has done it before. Not rocket science but there are some tricks, plus it would just be more difficult without a helper, so you might as well make that someone who knows what's what!

I still have all the reassembly of baffles, exhaust, etc. before flying but that's all basic stuff, just takes time.
 
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