The Engine Comes off Again

[A64Pilot]

Just saw this as I’m not on the forum every day.

 Couple of comments, first I don’t think the failure had anything to do with lower EGT. The amount of movement assuming the nuts didn’t back off is no more than the thickness of the paint, and that’s just not enough to affect combustion. 

Secondly departing jugs are and have been not uncommon on radials since long before I was born. Many retorque jugs on Radials every couple hundred hours and it’s not uncommon for them to torque up, that is get a little movement. Idea is to try to prevent blowing a jug of course. On them often before they blow they may start to leak a little oil, but as oil leaks are very common it’s often missed and not all do, some engines will continue to run with a blown jug, R-985 for one while the R-1340 will not. I would suspect a flat 4 cyl would not.

If you’re going to go to the trouble of breaking torque to retorque and I’m not suggesting you do, but you should go all the way to removing the nuts, oiling the threads and retorque it. However on most flat engines there is usually a lot of “stuff” that has to be removed just to access all of the nuts to check torque, it’s the majority of the work required to pull the cylinders.

With paint under the cylinders I don’t think retorqueing would have saved this motor, the fretting case halves make me think it lost torque long ago, maybe very soon after it was put into service.

As with everything this is just my opinion.

We all know these engines are very primitive designs, but I think due to weight they aren’t over built and they require a mechanic to keep things clean and be meticulous in assembly, frankly I’m surprised from what I see frequently that there aren’t more failures.

 

[gevertex]

5 hours ago, A64Pilot said:

Just saw this as I’m not on the forum every day.

 Couple of comments, first I don’t think the failure had anything to do with lower EGT. The amount of movement assuming the nuts didn’t back off is no more than the thickness of the paint, and that’s just not enough to affect combustion. 

Secondly departing jugs are and have been not uncommon on radials since long before I was born. Many retorque jugs on Radials every couple hundred hours and it’s not uncommon for them to torque up, that is get a little movement. Idea is to try to prevent blowing a jug of course. On them often before they blow they may start to leak a little oil, but as oil leaks are very common it’s often missed and not all do, some engines will continue to run with a blown jug, R-985 for one while the R-1340 will not. I would suspect a flat 4 cyl would not.

If you’re going to go to the trouble of breaking torque to retorque and I’m not suggesting you do, but you should go all the way to removing the nuts, oiling the threads and retorque it. However on most flat engines there is usually a lot of “stuff” that has to be removed just to access all of the nuts to check torque, it’s the majority of the work required to pull the cylinders.

With paint under the cylinders I don’t think retorqueing would have saved this motor, the fretting case halves make me think it lost torque long ago, maybe very soon after it was put into service.

As with everything this is just my opinion.

We all know these engines are very primitive designs, but I think due to weight they aren’t over built and they require a mechanic to keep things clean and be meticulous in assembly, frankly I’m surprised from what I see frequently that there aren’t more failures.

 

Those are interesting points. I have no idea what then could have caused #3 to lean so much cooler. Looking specifically at the delta EGT on #3 in the attached picture.

[PT20J]

Have you eliminated a bad probe?

[EricJ]

CHTs are fine, so if it'd been running like that for a while it may be the EGT probe.

 

[gevertex]

I'll check the probe if this persists after the engine reinstall. This started happening directly before the failed studs were discovered so no other diagnosis has been done.

[201Steve]

My engine had rusted exhaust studs and fretted case also, when we tore back down the Jewell build. At best, they are a lawn mower shop building aircraft engines. None of what they do follows any standard or best practice. It’s just a TLAR standard through the eyes of a mechanic bred from a brother sister conception.
 

i’m game for a throw down. Little Davie Jewell reads this forum so he’s listening now, but I would start by joining me in posting a pirep in every popular forum and Facebook group, writing reviews on Google, ForeFlight, AOPA directory, and any other place you’ve heard their name. I know for certain I’ve saved at least 2 or 3 chaps from the misery. 
 

id also let Don  and Paul Maxwell know @Pmaxwell @Dmax They have referred several people to them for some insane reason, even letting them build their own predator engine. 

best I can gather, Sam Jewell was a competent guy, how they got their start and whatever good results they once had, but he’s in his 90’s now and his son little Davie is a failure to launch situation and will eventually burn it to the ground. 
 

 

[A64Pilot]

Many things influence EGT, mixture is one of course.

It’s counterintuitive but lower compression runs a higher EGT, I think high compression is more efficient and it gets that way by harnessing more of the power from burning fuel and as these are heat engines it drops EGT. that’s my theory I don’t know if it’s correct or not.

But I can’t imagine a cylinder moving at most a few thousands of an inch would have any effect.

Edited October 25 by A64Pilot

[LANCECASPER]

On 10/24/2024 at 8:04 PM, 201Steve said:

My engine had rusted exhaust studs and fretted case also, when we tore back down the Jewell build. At best, they are a lawn mower shop building aircraft engines. None of what they do follows any standard or best practice. It’s just a TLAR standard through the eyes of a mechanic bred from a brother sister conception.
 

i’m game for a throw down. Little Davie Jewell reads this forum so he’s listening now, but I would start by joining me in posting a pirep in every popular forum and Facebook group, writing reviews on Google, ForeFlight, AOPA directory, and any other place you’ve heard their name. I know for certain I’ve saved at least 2 or 3 chaps from the misery. 
 

id also let Don  and Paul Maxwell know @Pmaxwell @Dmax They have referred several people to them for some insane reason, even letting them build their own predator engine. 

best I can gather, Sam Jewell was a competent guy, how they got their start and whatever good results they once had, but he’s in his 90’s now and his son little Davie is a failure to launch situation and will eventually burn it to the ground. 
 

 

I think it's already burned to the ground. Their website is down.

 

A frightening thought . . .  I actually called David for a brief conversation in early 2018 when I was about to do a Bravo conversion on a Mooney TLS.  (I was thinking of maybe just going ahead and overhauling it. I was in annual, the engine wasn't making metal. I could fly it up there and drop it off . . . and pick it up when he was done.)

After finding out that he had never done a Lycoming TIO-540-AF1B and having him tell me that it's just like the engine in Piper Mirage, which it's not, and then having him telling me that he had only done one of those also and they finally got it figured out, but it took them about six months. There were no obvious supply chain issues back then.  I thanked him for his time. My IA and I did the Bravo conversion with lot of help from Mooney, Lycoming and others and I was very happy with the outcome and very thankful that I never let them touch that airplane. It would have been a train wreck.

[gevertex]

I'll go ahead and share Jewell's initial response to my calls / email. I felt it was pretty defensive. They apparently went through my post history on Mooneyspace and because I talked about ground leaning, accused me of taking off with less than full mixture resulting in detonation. I have never taken off with anything other than a properly set mixture.

I did share the report from the IRAN with them, radio silence. The IRAN did not find any evidence of detonation. They are not going to voluntarily take responsibility for this. I have called a lawyer already.

It was also disappointing that the items covered in their overhaul were basically just the minimum legal requirements. To get an engine that would last for the next 2000 hours and 20 years or more, I had to have extensive additional work done.

George Sapp IO360A3B6D Response.pdf

[Slick Nick]

What a prick! It’s one thing to know nothing about overhauling engines, but it’s another to pretend like you do and keep charging people for your ineptitude. 

[gevertex]

6 hours ago, LANCECASPER said:

I think it's already burned to the ground. Their website is down.

 

A frightening thought . . .  I actually called David for a brief conversation in early 2018 when I was about to do a Bravo conversion on a Mooney TLS.  (I was thinking of maybe just going ahead and overhauling it. I was in annual, the engine wasn't making metal. I could fly it up there and drop it off . . . and pick it up when he was done.)

After finding out that he had never done a Lycoming TIO-540-AF1B and having him tell me that it's just like the engine in Piper Mirage, which it's not, and then having him telling me that he had only done one of those also and they finally got it figured out, but it took them about six months. There were no supply chain issues back then.  I thanked him for his time. My IA and I did the Bravo conversion with lot of help from Mooney, Lycoming and others and I was very happy with the outcome and very thankful that I never let them touch that airplane. It would have been a train wreck.

Perhaps they are out of business, not sure.  I was able to get him on the phone after the website went down.

[Rwsavory]

54 minutes ago, gevertex said:

Perhaps they are out of business, not sure.  I was able to get him on the phone after the website went down.

They probably neglected to pay the hosting fee. I recently heard they are getting a lot of engine work from folks in the trade. It sounds like serving retail customers may not be their forte, to say the least.