Overhaul review, Jewell Aviation and powerflow exhaust

[graham28105]

This is a clip from when I was breaking some new cylinders on my old "J" I sold which was a pretty well rigged plane. You can see on the MX-20 that GS was 170 kts and if you pause the clip the KTAS was 172 kts. The GS fluctuated between 170-174 in different direction so I felt it was correct but didn't do a formal 3 way. You can also see it was calm water in the Salton Sea. They are cylinders I had LyCon rebuild, port and flow balance which seemed to work.

I was considering the Powerflow but had no real reason to pull the trigger. If I needed to replace the exhaust I would have probably done it. The Powerflow exhaust 11.5 altitude optimization I felt was good since it would be DA. In the summer when I fly DA can easily meet or exceed 11.5 at cruise altitudes of 8.5-10.5. I cant remember anytime I haven't had a DA increase except for a few ski trips but I live in the South West. It's been hot out here:)

Was your fuel flow really 20gph!?

[carusoam]

Wait till you see break-in on an IO550...

Full MP, full rich, low altitude, for as long as it takes...

Best regards,

-a-

[wishboneash]

This is a clip from when I was breaking some new cylinders on my old "J" I sold which was a pretty well rigged plane. You can see on the MX-20 that GS was 170 kts and if you pause the clip the KTAS was 172 kts. 

 

Wow on the speeds! I can't get more than 18.8gph at sea level on take off. How did you get 20gph? Mine is an A3B6 engine so it is not as fast as the A3B6D engine with the 25deg timing.

[aaronk25]

I think the advertising lingo about optimized at 11.5 is just advertising talk. Plane starts slowing up at 11k.

I'd say its optimize for higher rpm greater than 2500rpm and -10lop to 50rop Max. It's really optimizes peak egt at higher rpm.

I don't see anything special at 11.5da

[kmyfm20s]

Sorry I was on vacation. The FF at that time I believe was reading 3% high but it did go up after the new cylinders.

[isaacpr7]

1999 factor overhaul. Propstrike in 2011, new main bearings cam and lifters. June 2014, 400 hours after new cam, cam failed one lobe wore down.

 

I had a propstrike back in 2012. The mechanic at the time said that it did not require an engine tear down inspection; however, three years later when I changed mechanic I was shown as per the AD that it did in fact require an engine tear down. Needless to say I may have to ship the engine off to be inspected before the engine can be airworthy again. If I was to send my engine to Jewell Aviation, how much do you think it would cost for the ispection if everything was found okay? How much does it cost to ship the engine as well?

[aaronk25]

I had a propstrike back in 2012. The mechanic at the time said that it did not require an engine tear down inspection; however, three years later when I changed mechanic I was shown as per the AD that it did in fact require an engine tear down. Needless to say I may have to ship the engine off to be inspected before the engine can be airworthy again. If I was to send my engine to Jewell Aviation, how much do you think it would cost for the ispection if everything was found okay? How much does it cost to ship the engine as well?

Give david or Sam Jewell a call they will tell you. The overhaul labor portion was 2-2500 so what ever the parts would be in addition. Other engine shops such as buldoc or popular grove charge 7500-8500 with parts....give them a call.

[isaacpr7]

After extensive research and calling Lycoming, it was determined that no engine teardown was required

[Guest]

After extensive research and calling Lycoming, it was determined that no engine teardown was required

I'm curious how they determined that no action was required. AD 2004-10-14 and Lycoming SB 475C define what a propeller strike is and the actions required, in this case at very minimum is removal of the accessory cover and inspection of the crankshaft drive gear, gear counterbore and replacing of the bolt whic holds the gear. This gear drives everything in the engine.

Clarence

[isaacpr7]

I'm curious how they determined that no action was required. AD 2004-10-14 and Lycoming SB 475C define what a propeller strike is and the actions required, in this case at very minimum is removal of the accessory cover and inspection of the crankshaft drive gear, gear counterbore and replacing of the bolt whic holds the gear. This gear drives everything in the engine.

Clarence

You are correct about the minimum requirements; however, all of these requirements can be met without engine teardown because they can be inspected and components replaced by removing the accessory cover (depicted on every diagram in the Mandatory Service Bulletin).

AD 2004-10-14 elaborates on why MSB 475C must be complied with. MSB 475C thoroughly describes the procedures for the inspection and is the mandatory reference which the AD refers to. Below I will summarize the procedures listed in 475C:

1. Examine the threads in the gear retaining bolt hole of the crankshaft. Insure that the tapped hole is clean and the threads are undamaged.

2. Check the condition of the dowel in the end of the crankshaft.

3. Check the pilot diameter of the counterbore on the end of the crankshaft for size and evidence of damage.

4. If the dowel has been removed, check the condition of the dowel hole in the crankshaft.

5. Install a new dowel in the crankshaft (if dowel has been removed).

6. Assemble the gear to the crankshaft using both a new lockplate and bolt.

7. Bend the lockplate against the bolt head.

8. A logbook entry, specifying the final bolt torque, verifying that the lockplate was properly bent in place against the bolt head and that the inspections and rework required by Lycoming Service Bulletin No. 475C were accomplished, should be made and signed by an authorized inspection representative.

Where people get confused is they come across SIB 533B (engine teardown and is not mandatory) which has nothing to do with what the AD wants you to comply with. Lycoming stated that this SIB is only mandatory for part 135 aircraft if it is part of their standard operating procedures, which in most cases they are. The SIB describes what procedures must be performed during an engine teardown and it throws a blurb in there about prop strike in one of its paragraphs; however, it is not regulatory in nature and it is not referred to comply with as per the AD.

Lycoming still leaves it up to the MX to determine if an engine teardown is required. This is based on the MX judgment and knowledge of the aircraft accident / incident histoy.

Hope this helps.

[N601RX]

There was a case just south of where I'm at that the crank gear bolt was left out entirely at overhaul. The engine ran for almost 500 hrs until it finally broke the dowel and left the instructor and student floating in the bay until rescued.

[Guest]

There was a case just south of where I'm at that the crank gear bolt was left out entirely at overhaul. The engine ran for almost 500 hrs until it finally broke the dowel and left the instructor and student floating in the bay until rescued.

Hard to imagine it would have run that long before failure. Some really luck people flying in those 500 hours.

Clarence

[Guest]

You are correct about the minimum requirements; however, all of these requirements can be met without engine teardown because they can be inspected and components replaced by removing the accessory cover (depicted on every diagram in the Mandatory Service Bulletin).

AD 2004-10-14 elaborates on why MSB 475C must be complied with. MSB 475C thoroughly describes the procedures for the inspection and is the mandatory reference which the AD refers to. Below I will summarize the procedures listed in 475C:

1. Examine the threads in the gear retaining bolt hole of the crankshaft. Insure that the tapped hole is clean and the threads are undamaged.

2. Check the condition of the dowel in the end of the crankshaft.

3. Check the pilot diameter of the counterbore on the end of the crankshaft for size and evidence of damage.

4. If the dowel has been removed, check the condition of the dowel hole in the crankshaft.

5. Install a new dowel in the crankshaft (if dowel has been removed).

6. Assemble the gear to the crankshaft using both a new lockplate and bolt.

7. Bend the lockplate against the bolt head.

8. A logbook entry, specifying the final bolt torque, verifying that the lockplate was properly bent in place against the bolt head and that the inspections and rework required by Lycoming Service Bulletin No. 475C were accomplished, should be made and signed by an authorized inspection representative.

Where people get confused is they come across SIB 533B (engine teardown and is not mandatory) which has nothing to do with what the AD wants you to comply with. Lycoming stated that this SIB is only mandatory for part 135 aircraft if it is part of their standard operating procedures, which in most cases they are. The SIB describes what procedures must be performed during an engine teardown and it throws a blurb in there about prop strike in one of its paragraphs; however, it is not regulatory in nature and it is not referred to comply with as per the AD.

Lycoming still leaves it up to the MX to determine if an engine teardown is required. This is based on the MX judgment and knowledge of the aircraft accident / incident histoy.

Hope this helps.

I understand the process, that's why I posted the reference the the AD and the SB.

What I am still not clear on is, while you did not have your engine removed and split, did you have the AD and SB complied with at the original prop strike or since then?

Clarence

[N601RX]

Hard to imagine it would have run that long before failure. Some really luck people flying in those 500 hours.

Clarence

I guess the crank gear is captured pretty well by the counterbore in the crankshaft and the oil pump shaft. It looks like gear just slowly wore into the dowel until it broke. There was no witness marks of the bolt ever been installed or torqued down on the gear or threads. I was very skeptical that it would run that long also after the CFII who was in the plane at the time told me what happened. Here is the report.

http://www.ntsb.gov/_layouts/ntsb.aviation/GeneratePDF.aspx?id=ERA12LA234&rpt=fa

[isaacpr7]

I understand the process, that's why I posted the reference the the AD and the SB.

What I am still not clear on is, while you did not have your engine removed and split, did you have the AD and SB complied with at the original prop strike or since then?

Clarence

Certainly did. It was complied with during two annuals ago.

[ltdoyle]

It's been a few years, are you still happy with the Jewell overhaul?  They have my engine now.  David

[rbridges]

I'm curious, too.  They're on my short list when the time comes.  

[carusoam]

Ask @aaronk25 regarding Jewell.... (invite)

Best regards,

-a-

[Flymac]

Just completed an overhaul at Jewell as well, hoping to get first startup next week and begin flying again!  I can echo the comments made in the post a few years ago still stand today, David was very helpful, patient with me answering all kinds of questions and checking in during the process.  Pricing was just as advertised on the website, no surprises, and timeline spot-on as he estimated (granted I think I missed the winter rush!) as engine came back before thanksgiving.  We had 2010 Hrs on our engine so hoping for a few knots back of performance would at least be something to feel good after this $$$$ process! 

[aaronk25]

Hi All.

It’s been a few years and I got around 500 hours on the engine. Not a single issue. Speed is within margin of error, best I can tell exactly the same as when the motor was just broken in.

I still don’t know if the extra steam under the cowl came from the power flow exhaust or jewel, but it runs great and oil consumption is a quart in 10hours or better.

Jewel is one of the best kept secrets!




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[LeeBurk]

Which Power FLow did you go with? Original design or shorter one?

[gsxrpilot]

JD (SWTA) was on the phone with Jewell about doing an engine for one of his customers, and also asking for a quote for my engine as well. When asking about lead times, Jewell said he's swamped. It's all Mooney engines. He doesn't know what happened but all of a sudden, every Mooney engine in the country needing an overhaul seems to be headed his way. 

The secret's out, it seems.

[aaronk25]

Which Power FLow did you go with? Original design or shorter one?

Gen 2, is what I got, that latest one.


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[Yooper Rocketman]

Mine was completed a couple months ago, lost some time for the installation and a couple issues with parts found during installation that needed changing and took a little time to get.  I just hit 25 hours on it and changed out the mineral oil as the consumption is stable and the new owner (sale date set for 12/27) wanted the mineral oil out.  Having a bit of concern there might be a little more oil stabilization pending, my FBO/maintenance shop gave me a Phillips multi grade rated for break-in AND regular service.

So my engine had 2100 hours on a 1600 TBO.  It has power like I don't remember (I bought it with a fresh OH, due to prop strike, on a 300 hour since new engine).  That may be because it had degraded slowly towards the twilight of it's life and the past TBO time.  But on the other hand, my Lancair is about the same weight and well over double the HP, so to be impressed with the Rocket engine performance, it must be pretty good!

Jewell did a great job for me.......my FBO is used to engines coming from shops where the rebuilds have been dyno run, so they were not as happy because they had to perform more work.  But then I ended up a good $20K under where I would have been with one of those shops too.

Very Happy!

Tom

 

 

[AlexLev]

Had my Jewell Overhaul in February, they did a great job so far. About 140 hours on the engine so far; consumption is currently about 1qt per 20 hours, on an O-360. I flew the plane to them for the OH and they did the R&R and stayed on budget and on time.