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Lycoming SB 632 7/17/2017

Apexeon

Member
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Yup, our engine is on there. In fact, I'd say if you bought a Lyc in the past year, you're on there.
John
 
Yeesshhh.... this one might get ugly.

I have not read in detail many Lycoming SBs. What I find interesting on this one is the warranty information is front and center, I have never seen the warranty information so prominently displayed before.

Tim
 
I have not read in detail many Lycoming SBs. What I find interesting on this one is the warranty information is front and center, I have never seen the warranty information so prominently displayed before.

Tim

That, and the time of compliance within next 10 hours to inspect....

Lycoming must realize they really stepped in something here - curious to hear the backstory on this one. At least its a relatively small time window for production.

My engine is not on the applicable list, I dodged this bullet.
 
Big bummer. I'm always amazed when something like this comes up as the engines really haven't changed since the 50's.

Have they ever been perfect or does one SB eventually just create another down the road after material and or procedures change? I'm guessing it is always work in progress after looking at the 74 pages of Service Bulletins Letters and Instructions.

Wow, tough business...
 
Can you replace the con-rods and bearings without splitting the case? Doesn't look practical to me but I've never opened an engine either. This looks like a pretty invasive fix to a nearly new engine.
 
I didn't see a date for the engine/parts shipped but checked my S/N and luckily I am not affected
 
Can you replace the con-rods and bearings without splitting the case? Doesn't look practical to me but I've never opened an engine either. This looks like a pretty invasive fix to a nearly new engine.

It is invasive but can be done.
 
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Is Your Engine Affected?

Chances are that most of the affected engines are factory or Thunderbolt built engines shipped from November 2016 - February 2017.

If you engine was overhauled/repaired in the field prior to 11/2016, you will not be affected.

From my shop if your engine was overhauled/repaired between 11/2016 and 2/2017, you most likely will not be affected as the shop we use for these repairs almost exclusively uses Superior rod bushings, except for parts under EASA regulations. But, if you have a question, feel free to drop me an email.
 
Can you replace the con-rods and bearings without splitting the case? Doesn't look practical to me but I've never opened an engine either. This looks like a pretty invasive fix to a nearly new engine.

Connecting rods and con-rod bearings yes, main bearings no...
 
IO -390 ?

I don't see any IO -390 engines on the SB List. I hope this is correct. I thought they were the same cylinders as the 580 that are on the list. Perhaps the rods are unique to the 390 and the list is correct.
 
Legalese

A quote from the SB

"YOU MUST COMPLETE THE ?REQUIRED ACTION? IN THIS SERVICE BULLETIN. IF YOU DO NOT COMPLETE THE ?REQUIRED ACTION? IN THIS SERVICE BULLETIN, AND THE CONNECTING ROD BUSHING MOVES OUT OF PLACE, THE CONNECTING ROD CAN FAIL AND CAUSE UN-COMMANDED STRUCTURAL ENGINE FAILURE."

I love that term, "Un-Commanded Structural Engine Failure", as opposed to, I guess, a "Commanded Structural Engine Failure".

I am wiring the cockpit right now. I am thinking of putting in a switch with the notation of "Commanded Structural Engine Failure", just in case I need to kill the engine at some point. Just to be safe, I will make it a guarded switch.
 
Rod bushings

Just checked my overhauled parts from aircraft specialties that were done in febuary. They used superior rod bushings SL 13923A so mine were not effected. Only lycoming parts affected. This will be quite expense for some folks, mainly lycoming.
 
A quote from the SB

"YOU MUST COMPLETE THE ?REQUIRED ACTION? IN THIS SERVICE BULLETIN. IF YOU DO NOT COMPLETE THE ?REQUIRED ACTION? IN THIS SERVICE BULLETIN, AND THE CONNECTING ROD BUSHING MOVES OUT OF PLACE, THE CONNECTING ROD CAN FAIL AND CAUSE UN-COMMANDED STRUCTURAL ENGINE FAILURE."

I love that term, "Un-Commanded Structural Engine Failure", as opposed to, I guess, a "Commanded Structural Engine Failure".

I am wiring the cockpit right now. I am thinking of putting in a switch with the notation of "Commanded Structural Engine Failure", just in case I need to kill the engine at some point. Just to be safe, I will make it a guarded switch.

Sort of like "Rapid Unscheduled Disassembly" :)
 
A quote from the SB

"YOU MUST COMPLETE THE ?REQUIRED ACTION? IN THIS SERVICE BULLETIN. IF YOU DO NOT COMPLETE THE ?REQUIRED ACTION? IN THIS SERVICE BULLETIN, AND THE CONNECTING ROD BUSHING MOVES OUT OF PLACE, THE CONNECTING ROD CAN FAIL AND CAUSE UN-COMMANDED STRUCTURAL ENGINE FAILURE."

I love that term, "Un-Commanded Structural Engine Failure", as opposed to, I guess, a "Commanded Structural Engine Failure".

I am wiring the cockpit right now. I am thinking of putting in a switch with the notation of "Commanded Structural Engine Failure", just in case I need to kill the engine at some point. Just to be safe, I will make it a guarded switch.

You could put it right next to the "Chem Trail" switch.
 
More BAD NEWS to follow if you ask me.


History, my Advanced Pilot seminars colleague down here in Australia and one of our mutual friends who between them are the countries biggest and best engine shops started to detect this problem almost 2 years ago. As usual and sadly, Lycoming were not very forthcoming and even CASA were not.

The bad news is likely to be like all these SB's where they start at a date range (and then shortly after the date range extends.

Now why do I say this? Well some of the engines with very much failed parts at <50% hours were overhauled in 2011. :eek:

Think about how Lycoming might be trying damage control methods here. Continental are doing funny things about timing gears too at present. There is a lack of complete transparency going on in the eyes of many who are not fools in the industry.

I smell a rat. :mad:

I hope I am being too harsh and skeptical, but even my 2008 build IO540 with 1500 hours on it now is potentially a victim, purely because I know this problem existed at least back as far as 2011. And it was the these very same parts that started the process off at the end of 2015/early 2016.

I will try to post the photos later, after I get permission to publish them from my friend who started this all off.

You have to ask why it has taken over 18 months for the SB to appear.

Time will tell.
 
Does anyone know what the root cause of the problem is? Are other manufacturers' rods potentially affected? Needing some RCCA analysis here...
 
More BAD NEWS to follow if you ask me.


History, my Advanced Pilot seminars colleague down here in Australia and one of our mutual friends who between them are the countries biggest and best engine shops started to detect this problem almost 2 years ago. As usual and sadly, Lycoming were not very forthcoming and even CASA were not.

The bad news is likely to be like all these SB's where they start at a date range (and then shortly after the date range extends.

Now why do I say this? Well some of the engines with very much failed parts at <50% hours were overhauled in 2011. :eek:

Think about how Lycoming might be trying damage control methods here. Continental are doing funny things about timing gears too at present. There is a lack of complete transparency going on in the eyes of many who are not fools in the industry.

I smell a rat. :mad:

I hope I am being too harsh and skeptical, but even my 2008 build IO540 with 1500 hours on it now is potentially a victim, purely because I know this problem existed at least back as far as 2011. And it was the these very same parts that started the process off at the end of 2015/early 2016.

I will try to post the photos later, after I get permission to publish them from my friend who started this all off.

You have to ask why it has taken over 18 months for the SB to appear.

Time will tell.

And you can thank tort law and lawyers for the lack of transparency.

Tim
 
Difference between XIO and YIO 320

So what's the difference between the XIO-320-D1A RT that Vans sells and the one on recall the YIO-320-D1A ?
 
Not sure why Van's markets the experimental engines as "X" designation, but the engines you receive from Lycoming are designated "Y". I ordered an XIO-360 M1B from Van's and my data plate shows YIO-360-M1B. Must be a licensing or marketing agreement.
 
So...for the uninitiated among us;

Who pays for the Service Bulletin to be complied with? Standard Warranty thought process would say that Lycoming foots the bill, but that seems unlikely...

Is the industry standard that the manufacturer gets off financially untouched putting out an unsafe product, or will they pay for everyone's engines to get fixed?
 
Follow up from my earlier post, these bushes are a new design from a year or so ago, and they were a "new design"........wonder why the new design, but now the new one is worse!


I went back through my emails about this and the email was from January 2016, but the issues had been building with many incidents found by just a few shops in Australia on FACTORY engines.

One dated back to 2005 :eek:

This is just the beginning for sure.

CASA and the FAA have been aware of this problem since 2015, and so have Lycoming. I can only wonder if a little aviation outpost like Australia has seen so many why it has not been a bigger fuss in the FAA's backyard.

Maybe Lycoming like to send all their junk engines down under?

So there are TWO seperate bush design problems, the older ones are a problem but the new ones are far worse!

What the heck is going on Lycoming???
 
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You are correct. I was only looking at the LW-11750 rod dates. Sorry that you are affected. Hope it won't ground a lot of individuals for OSH!

Rhonda, so what is (your opinion) the design issue? Are the Lyc bushings just dimensionally poor or is the bushing material too soft and they are yielding and losing preload?

Sorry for all the questions, but one more - are the bushings installed with rod and bushing cold and pressed, hot, or light pressed then internally burnished to expand and reamed to final dimension?
 
Keep in mind that even though it's an MSB (mandatory SB) there is nothing "legally" mandatory about any SB even in the "certified" world until it becomes an AD.
 
Direct this to Lycoming also

Rhonda, so what is (your opinion) the design issue? Are the Lyc bushings just dimensionally poor or is the bushing material too soft and they are yielding and losing preload?

Sorry for all the questions, but one more - are the bushings installed with rod and bushing cold and pressed, hot, or light pressed then internally burnished to expand and reamed to final dimension?

The best post yet that can lead us forward, thanks Bill.

Lots of 150 HP 320's (Low CR) are still running at over 3500 hours. Lots of old 540's go well past 2000 hours, so I would deduct that this is either a soft bushing (Material) problem or a dimension (not enough press fit) problem, unless they had a design or process change. However until somebody presents more factual information as to the cause we are all in the dark.
 
I have a YIO-360-M1B affected by the SB. Here are the results of my research so far. The ST-531 tool is not available in Aviall's system yet nor did they have a price as of this morning. The rep at Lycoming thought is would cost around $200 and he felt there should be plenty available. This tool is new and specially built just for this SB. The connecting rods that use the stretch bolts are not used in most of the engines we have, they are primarily used in the turbo charged and high compression engines ( per Lycoming rep ). Best I can tell they are not used in my engine. This means all I need is a torque wrench for the Connecting rod nuts. The top overhaul gasket kit P/N 05K22949 was not listed in Aviall's system. ( Aviall is Lycoming's largest distributor ) Aviall implied they would contact Lycoming to get it setup. I spoke to two people at Lycoming and no one would venture a guess as to how many defective bushings may be in service. I am going to purchase the ST-531 tool and can pass it on to someone else when I am finished.
 
I spoke with someone at AERO yesterday. The ST-531 will be $216.00 + shipping and can be returned for a refund of $116.00 ($100.00 rental, essentially). However, as noted, it's not widely available. .... Just spoke with another distributor and they are also waiting on the tool.
 
Follow up from my earlier post, these bushes are a new design from a year or so ago, and they were a "new design"........wonder why the new design, but now the new one is worse!


I went back through my emails about this and the email was from January 2016, but the issues had been building with many incidents found by just a few shops in Australia on FACTORY engines.

One dated back to 2005 :eek:

This is just the beginning for sure.

CASA and the FAA have been aware of this problem since 2015, and so have Lycoming. I can only wonder if a little aviation outpost like Australia has seen so many why it has not been a bigger fuss in the FAA's backyard.

Maybe Lycoming like to send all their junk engines down under?

So there are TWO seperate bush design problems, the older ones are a problem but the new ones are far worse!

What the heck is going on Lycoming???

David, according to the MSB, the bad batch of bushings shipped between 18 Nov 2015 and 15 Nov 2016
My con rods were reconditioned in June of 2015 BEFORE the bad batch shipped.
Are you saying that previous bushings are defective also?
Also, I'm very interested in knowing what the specific problem is, was it a materials issue or were they dimensionally incorrect?
Tim
 
bushings

The bushings are dimensionally incorrect! I have heard from a large shop that they had issues back on 2015 before the MSB and Lycoming did nothing.

Jesse
 
Wow, I would think a competent machinist would check them first and even if he didn't he would notice they press in easier than they should.
I hope they don't expand the SB, so far I'm good by 5 months.
Tim
 
Tim, there are two problems at play here. The recent bushes from late 2015 were most likely but I can't confirm, to resolve issues that go back to around 2011 and who knows when else.

Strangely the new design that is subject to the MSB were still being shipped to customers down here in Feb this year.

I am guessing this is not the end of it.
 
Dear Folks Im very angry, we are building a RV-10 and the engine is in the original crate. It is affected by the SB and lycoming said that they will not change the engine. These is a very bad new and speaks bad of Lycoming responsability.

They said that we have to send the engine at our cost to a service station and open the NEW engine!!

I always speak fine about lycoming engines but these case is inacceptable.
 
We're at KOSH (drove). Our -M1B is likely on the list based on the time frame of the purchase. Bet the Lyc booth will be crowded. :mad:
 
Saw the tool

The S/B tool was at the OSH Lyc. booth yesterday. Was told they are making ~40 per day.

Also, that Lyc. will send me a crate for my never run 360-M1B and pay freight both ways if I wish. The engine is currently mounted on the airframe with all sensors and ascessories connected. I'll first see if a local shop will send a mechanic and do the job in my hangar and for the allowed hours.

I talked to two engine shops at OSH today and both thought the job could be done in the warranty allowed hours. :rolleyes:
 
Yep.

I saw it too.

I was surprised to receive the tool in the mail yesterday from Lycoming along with the top overhaul gasket kit. I expected it to take a lot longer given the high demand. I'm planning to have a local A&P do the work for me while I watch.
 
Do Not Ignore This SB

I spoke separately with a tech rep and the head of product support at Oshkosh about SB 632. The connecting rod bushings from an outside supplier assembled properly. Only when field failures occurred did the company realize that some did not meet specs. The failure modes are 1) making metal, 2) loose piston pins and plugs banging around in the cylinder and 3) connecting rod breaking. The company showed pix of broken connecting rods that failed IN FLIGHT.

I asked about operating with frequent oil analysis and filter cuts to early detect an impending failure. Both said no, as some failures occurred less than 25 hours after clean oil changes.

As mentioned above, a demonstration showed that the test with their tool is quick and simple. Exposing the connecting rods is not. Lycoming's policy is to re-hone and re-ring a cylinder if the piston is ever removed, even on new engines with only test cell time. The reps stressed pulling the cylinder only enough to remove the piston pin and caps, leaving most of the piston and the rings in the cylinder.

For those of us who bought engines through Vans, that company is our dealer and the conduit for warranty reimbursement. I hope that we will hear something about procedures once Vans' product support persons return from Wisconsin.

FWIW, both had a chagrined attitude and said that Lycoming wanted to make things right.
 
For those of us who bought engines through Vans, that company is our dealer and the conduit for warranty reimbursement. I hope that we will hear something about procedures once Vans' product support persons return from Wisconsin.

I don't think you need to go through Van's. I bought my engine and prop through Van's about 16 months ago. When the SB was first released I spoke with Lycoming and they told me I could work with any Lycoming distributor. I contacted Triad and they are handling all the warranty claims for me. In fact, it was less than a week from when I contacted them to when I had the tool and top overhaul gasket kit in hand. As mentioned in a previous post, I was very pleasantly surprised how quickly they responded. Because I'm just a single experimental customer whose not even flying yet, I was anticipating a long wait for the tool.

Obviously I wish I didn't have to deal with tearing down a bran new engine that's only run for 0.6 hours on my airplane. But stuff happens. And so far my experience with Lycoming and Triad has been surprisingly very positive.
 
In fact, it was less than a week from when I contacted them to when I had the tool and top overhaul gasket kit in hand.

I wish I had the same experience.

When the SB came out, I started calling distributors. The first I called I left a message, which they never returned. The next I called said they didn't want to talk to me, they wanted to talk to a mechanic who would be doing the work (on an non-certificated engine??). I had an A&P call them back, but he got nowhere.

Finally I found a company where I could speak to a reasonable person, and got the tool and gasket kit ordered last Friday. I called back again this past Friday (a week later) to find out they still haven't received ANY of the tools yet for the people who were even ahead of me in line for them. I asked if Lycoming was preferring one distributor over another, since I've heard of others already getting the tool. He was very doubtful, and said he if found out that was happening there would be some major repercussions.

I just got my RV-8 airworthiness certificate 3 days ago. At this point, no clue when I'll actually be able to go flying though. However, I'm also at peace with the ordeal knowing that I'm glad I wasn't one of the unlucky ones who found out about the bad bushings the hard way.
 
When I'm finished with the tool I'll post here (hopefully early this week). I'll send it to anyone still waiting. Then they can send it to someone else, etc.
 
SB-632 completed

I order the tool and gasket kit from Aircraft Spruce the Friday before OSH. It arrived Last Friday. I removed the cylinders today performed the inspection and reassembled the engine. All my rod bushings are fine ( IO-360-M1B ). I had already removed the baffling last week. The first cylinder took about 2 hours ( this does not count time to remove and replace exhaust, intake runners and oil drain lines ), after that they were about an hour each. It is real touchy trying to keep from exposing the rings. I laid a piece of carpet under the engine in case I dropped anything and it save a lifter and one pin button. I removed and replaced the cylinders one at a time which negates the need for the torque plates. I think I spend more time assembling the documentation and lubricants needed then it took to do the work. I received my engine June 2016 and I have not run it. The date code on the connecting rods was 12/15/15.
 
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Affected

I also have a brand new 540 in the crate that was purchased through Vans. Called and spoke to Lycoming and they are covering all costs to send the engine back, inspect, fix, return. Luckily it is not installed on the plan yet and still in the box. Still a pain but nearly as bad as some I would suppose.
 
Runaround

As instructed by Lycoming, I contacted Vans as my engine distributor asking how to obtain the tool and gasket kit and for instructions about later submitting a warranty claim. My email to Support, which explained that I was referred by Lycoming, was answered by Fedosia in the Parts Dept with this statement, "If your engine is on the list for the service bulletin contact Lycoming for questions."

That is hardy the response I expected after giving Vans $47,000 for a new engine. Has anyone else gotten better info as to how Vans will handle this situation?

Meanwhile I sent my questions to Support and Fedosia again.
 
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