Lycoming Connecting Rod Bushing AD 2024-21-02

[MikeOH]

Just got this email notification:
https://drs.faa.gov/browse/excelExternalWindow/FR-ADFRAWD-2024-25365-0000000000.0001?modalOpened=true

Looks like mandatory oil sampling for metal (bronze) is required starting on 12/5/24 for nearly all Lycoming engines with the suspect bushing and shipped in a date range roughly from 1/30/2009 to 2/14/17.

That's my read of it, others chime in if that's not accurate.

Many of us probably aren't affected as that date range is well past when our engines were last apart!

Pretty good news for Blackstone Labs, I would think

[haymak3r]

lol. you BARELY beat me. I will remove my thread..

[EricJ]

I don't see a requirement for spectrographic analysis, just a visual inspection of the filter media for bronze particles.

[AndreiC]

Well, my engine was overhauled in 2012, and in talking to Penn Yan (the overhauler) it seems that it might have the affected bushings. I will ask Penn Yan if visual inspection of the filter is enough or if I need to send the oil off. 

Do any of you guys know if these bushings would be replaced when cylinders are replaced? I got all new cylinders in 2021 (so past the affected dates), but I see no mention of any bushings being replaced.

[MikeOH]

Hmm, based on @EricJ's comment this is looking like a 'nothing burger'...doesn't everyone look for metal particles when performing an oil change?  This is starting to seem like a pretty silly AD.

[AndreiC]

After having read both the AD text and the Lycoming service bulletin it refers to, I am quite a bit more confused. Lycoming says that one has to inspect the rod bushings and worry about them if at least 6 bronze "chips" are found in the oil filter or suction screen, or at least 3 bronze chips and 3 aluminum chips are found (in which case one has to inspect the pistons as well).

However, the AD text refers to the case when "any bronze metal particulates are found and the source is identified as the connecting rod bushings". According to Lycoming there is a significant distinction between bronze chips (less than 3/16" but larger than 1/16) and small dust-like pieces (smaller than 1/16").

What are we supposed to do if we find a few bronze dust-like pieces? Inspect the bushings or not?

[N201MKTurbo]

Sounds like CYA to me. 

When I rebuilt me engine, I sent the rods to Aircraft Specialty Services, who replaced the bushings. Does the AD affect them or just rods rebuilt from Lycoming? Or was it any engine that used Lycoming bushings? I would have to dig into the paperwork to see if they told me which bushings were installed.

[EricJ]

12 minutes ago, N201MKTurbo said:

Sounds like CYA to me. 

When I rebuilt me engine, I sent the rods to Aircraft Specialty Services, who replaced the bushings. Does the AD affect them or just rods rebuilt from Lycoming? Or was it any engine that used Lycoming bushings? I would have to dig into the paperwork to see if they told me which bushings were installed.

Yeah, it's not straightforward.   My engine was originally built well outside the covered date ranges, but got an IRAN in 2015.    I looked up the IRAN record and none of the affected parts were on the part list, and there was no indication that the bushings were touched.   Seems like an NA to me.

[DCarlton]

My engine was overhauled around 2016.  Planning to pull the logs soon and then sit down with a mechanic next Friday to review findings if any.  Was just about to drop serious $$ on bladders in Dec / Jan.  Hoping I escape this one.  Like Rosanne Rossana Danna used to say...  

[dzeleski]

Sigh, I have a 0 time engine that was delivered 1/23/2014. I don’t have any of the matching part numbers but I might have to give Triad a call. I always cut the filter open and send out the oil for testing. It’s never reported any brass.

[802flyer]

(g) Required Actions

(1) At the next oil change or within 4 months after the effective date of this AD, whichever occurs first, and thereafter at every oil change until the bushing replacement required by either paragraph (g)(3) or (4) of this AD is done, perform a visual inspection of the engine oil filter, oil pressure screen, and oil suction screen (depending on the engine configuration) for bronze metal particulates. The actions required by this paragraph may be performed by the owner/operator (pilot) holding at least a private pilot certificate and must be entered into the aircraft records showing compliance with this AD



Looks like logbook entries for oil changes just got a bit more verbose


Sent from my iPhone using Tapatalk

[jetdriven]

Sounds like you have to pull the engine oil suction screen every oil change too now which is going to be a little bit more expensive every time.

[Shadrach]

16 hours ago, EricJ said:

Yeah, it's not straightforward.   My engine was originally built well outside the covered date ranges, but got an IRAN in 2015.    I looked up the IRAN record and none of the affected parts were on the part list, and there was no indication that the bushings were touched.   Seems like an NA to me.

I am treating it the same way.  We IRAN'd in 2010. The main  bearings were replaced, but the rod bearings and bolts remained in situ.  Not applicable.

[ArtVandelay]

I overhauled in 2019 so this shouldn’t be an issue, but when I look at the logs I don’t see any rod assemblies, just individual parts. And there’s no serial numbers so I guess they can only go by the dates. I wonder if shops will check their records and send out notices if for no other reason than to protect against liability.

[cbarry]

On 10/31/2024 at 1:35 PM, MikeOH said:

Just got this email notification:
https://drs.faa.gov/browse/excelExternalWindow/FR-ADFRAWD-2024-25365-0000000000.0001?modalOpened=true

Looks like mandatory oil sampling for metal (bronze) is required starting on 12/5/24 for nearly all Lycoming engines with the suspect bushing and shipped in a date range roughly from 1/30/2007 to 2/14/17.

That's my read of it, others chime in if that's not accurate.

Many of us probably aren't affected as that date range is well past when our engines were last apart!

Pretty good news for Blackstone Labs, I would think

I think you meant to state a beginning date of 1/30/2009.

[N201MKTurbo]

38 minutes ago, ArtVandelay said:

I overhauled in 2019 so this shouldn’t be an issue, but when I look at the logs I don’t see any rod assemblies, just individual parts. And there’s no serial numbers so I guess they can only go by the dates. I wonder if shops will check their records and send out notices if for no other reason than to protect against liability.

Who did your engine? If it was a field overhaul, they probably were done in house or sent to a machine shop like Aircraft specialty Services. When I did my engine I sent them out. The paperwork I think just said Reconditioned rods per Lycoming service manual. They obviously had new bushings when they came back. I will have to dig up the receipts to see if the bushing manufacturer is listed. They could be Superior. Mine falls outside the time span, so it doesn't really matter to me. I haven't read the AD yet, does it apply to all Lycoming engines, or just engines from Lycoming?

[jetdriven]

Any engine that may have these Lycoming rod bushings installed is affected.  

[MikeOH]

44 minutes ago, cbarry said:

I think you meant to state a beginning date of 1/30/2009.

UGH!

Fixed, thank you.

[PT20J]

So, my engine was rebuilt by Lycoming in Sept 2018. I emailed Lycoming and asked if my engine was subject to the AD figuring that since they built it, they should know. They responded that their records show that it left the factory with 77450 connecting rods. Well, I could have figured that out from the IPC. So, I emailed them again pointing out that the AD references specific "ship" dates for the various connecting rods and asked how I could determine what the ship date was for the rods in my engine. It's late on a Friday, so I may not get a response until next week.

[jetdriven]

That AD affected period ends feb 2017 so you’re likely good. 

[N204TA]

26 minutes ago, PT20J said:

So, my engine was rebuilt by Lycoming in Sept 2018. I emailed Lycoming and asked if my engine was subject to the AD figuring that since they built it, they should know. They responded that their records show that it left the factory with 77450 connecting rods. Well, I could have figured that out from the IPC. So, I emailed them again pointing out that the AD references specific "ship" dates for the various connecting rods and asked how I could determine what the ship date was for the rods in my engine. It's late on a Friday, so I may not get a response until next week.

“This AD applies to Lycoming Engines (Lycoming) model engines that have an affected part and part number (P/N) installed and are assembled within the ship date range, as specified in Table 1 to paragraph (c) of this AD.”

It sounds like the ship date is for the assembled engine, not just the connecting rods.

[PT20J]

39 minutes ago, jetdriven said:

That AD affected period ends feb 2017 so you’re likely good. 

 

31 minutes ago, N204TA said:

“This AD applies to Lycoming Engines (Lycoming) model engines that have an affected part and part number (P/N) installed and are assembled within the ship date range, as specified in Table 1 to paragraph (c) of this AD.”

It sounds like the ship date is for the assembled engine, not just the connecting rods.

I missed that. It sounds like the AD is written from the perspective of engines assembled at the Lycoming factory and the ship date applies to the date the engine left the factory. If it was field overhauled then I'm not sure how you would determine if your engine is affected. 

[bigmo]

For once. I win.

[jetdriven]

27 minutes ago, PT20J said:

 

I missed that. It sounds like the AD is written from the perspective of engines assembled at the Lycoming factory and the ship date applies to the date the engine left the factory. If it was field overhauled then I'm not sure how you would determine if your engine is affected. 

When the parts left the factory I think.  Still reading 

[EricJ]

48 minutes ago, PT20J said:

 

I missed that. It sounds like the AD is written from the perspective of engines assembled at the Lycoming factory and the ship date applies to the date the engine left the factory. If it was field overhauled then I'm not sure how you would determine if your engine is affected. 

That was my first read, that it intends to address engines shipped from Lycoming.   However, it doesn't say that explicitly, and leaves a lot to interpretation.   It could be read that it was intended to include anything assembled in the field during the specified times with the listed part numbers.   I don't know why the assembly date would drive, though, as one would think the batch of the intalled part would be more important.

I think the bottom line is that it is just a very poorly written AD.  Regardless of how the AD is disposed in your logbook, I think it'll be worthwhile to pay attention to your filter media for bronze chips for a while.