Extreme CHT temps immediately after takeoff - 2nd post-maint flight that day - Mayday.

[TheMooneyAnomaly]

This is a sad and frustrating one.

Bought my 1967 (1968 serial) M20F in December.  The last 5 months, it spent most of its time in the avionics shop getting a beautiful upgrade, all Garmin - G3X, 355, GFC500, radio panel, second radio, transponder, G5, new panel itself.  

Bruce Jaeger installed the Mooney Spatial interior and reconditioned my upper plastics.

A local upholstery shop made beautiful new seats.

Mechanic installed new PowerFlow exhaust, side windows, hockey pucks, steering horn, and more.

- break -

Thursday, the aircraft had its first post-maintenance flight.  That afternoon, my mechanic and a CFI took it out for a beautiful ~30 min flight.

The 14 month old (overhauled) 80 hour 200hp IO-360 A1B motor did a great job. So did the avionics.

They both came back with great reviews and the avionics FDR showed fantastic numbers.

Three hours later, I took it out for a solo run.

Soon after takeoff, I noticed my climb performance wasn't all that great and my temps were rising. I should have turned around immediately - please believe me that I have self-roasted enough on this one. It took me maybe a full minute to decide to head back - and I didn't even take the most immediate route back, making a big fat pattern.  Again, I've roasted myself plenty so please be gentle with me... though I did at least make it back to the runway.

My climb performance, over the course of a couple of minutes, went from +250fpm to -350fpm with speeds below 100mph. My altitude capped out at 700 ft.

I'll let these Savvy charts and comment from Savvy detail the actual stats.

4 SavvyAnalysis charts posted in the images below - 2 of the pre-incident flight, showing great numbers.  2 of the incident flight, showing nightmares.  The only difference is that the second table in the images I alternate between altitude & airspeed in one, fuel flow & fuel pressure in the other.

You'll see that the temps were basically fine while rolling down the runway... but almost immediately got out of hand in the air.

 

CHT temps ran away, likely causing the oil temp runaway, likely causing the low oil pressure.

Fuel flow wasn't amazing but it was livable. 

Manifold pressure was plenty.

 

Analysis from Savvy:

Cyls 1 & 2 suffered a pre-ignition likely detonation event from an overly lean mixture, suggest carefully checking for any debris/dirt in the #1 and #2 injectors. Max FF is a bit low but okay and likely not yet calibrated, so FF may indicate a bit lower than actual till k-Factor is properly calibrated.  

CHTs 1 & 2 above redline for 7 min peaking to CHT2 737F and CHT1 680F 
Oil temp above redline by 55F for 6 min peaking at 297F 
Oil pressure below limits for 7 min, dropping to 46 psi 

 

What the team has reported, thus far:

No intake blockage. 

No intake leaks.

No exhaust blockage.

Running the fuel pump with the injectors sticking in cups showed equal and consistent flow, indicating injector blockage unlikely.

White paper test showed no easily discernible signs of Jet A.

Exhaust tubes for cylinders 1 & 2 dyed blue from heat.

Intake tubes for 1 & 2 show heat damage near the heads.

Cylinders 1&2 show obvious signs of detonation.

Pistons 1&2 appear sand-blasted.

Left mag 25 degrees.

Right mag 27 degrees.

The successful flight earlier in the day was entirely operated on the right fuel tank; immediately after start-up, I exclusively ran on the left fuel tank.  This introduces some suspicion on whatever was coming from the left fuel tank.

 

The cause itself remains unknown.  The mystery is driving me mad.  The (probable) loss of a sub-100 hour engine is driving me mad. And the flight itself attempted to kill me. 

The current plan:

 

1. Send fuel from each tank to the lab for anlysis
2. Drain the oil into a 5 gallon pail with a paint strainer or 1000 micron (or tighter) screen. Observe the debris. Observe the oil. Glittery silvery oil is typically fine aluminum and may not have damaged other components. Chunkier metal flakes are usually steel and will have damaged other engine components.  Do not discard the oil.
3. Send oil to the lab for analysis
4. Scope all 4 cylinders. Detail the condition of each cylinder, piston, valve.
5. Since there was detonation, pull connecting rods and check the bearings (start with the hottest ones). The bearing insert will tell you if there is contamination. They would be impregnated with foreign material.
6. If the bearings and oil are not a mess, discard #1 and #2 cylinders, replace.
7. If questionable, discard #1 and #2, send #3 and #4 for inspection
8. If bearings and oil look bad, send entire engine out
9. Check age and inspect interior of all fuel hoses in all areas, including from tank, connections to the transducer, fuel splitter, etc. Also check for blockage and debris.
10. Inspect inside the fuel flow divider.  We have seen debris in there that affects 2 or 3 cylinders - or sometimes just 1 cylinder but it changes cylinder from time to time.
11. Inspect fuel tanks for debris, growth, contamination, etc.
12. Inspect fuel servo.
13. Pull finger screen from servo, inspect. 
14. Inspect all screens.
15. Pull the manifold off and inspect.

Mechanic wants to do some ground runs before tearing things down.

 

I'm really upset about this.  Everything was beautiful and perfect... and just seconds into my first flight in this aircraft in months... the engine tore itself up.

The financials of this will be a significant challenge... and if we never get the root cause mystery solved, then how do I know that anything is resolved?

Just groaning out loud at this point after multiple nights of terrible sleep.

[TheAv8r]

Wow… I am so sorry to hear this. This royally sucks, and I know nothing I can say will make that better. My only suggestion at this point is if the engine only had 80hrs on it and was freshly overhauled, all reputable OH shops have a warranty, you should be within that. It might be an option if nothing that was installed caused it. 

[Oscar Avalle]

This is a sad and frustrating one.
Bought my 1967 (1968 serial) M20F in December.  The last 5 months, it spent most of its time in the avionics shop getting a beautiful upgrade, all Garmin - G3X, 355, GFC500, radio panel, second radio, transponder, G5, new panel itself.  
Bruce Jaeger installed the Mooney Spatial interior and reconditioned my upper plastics.
A local upholstery shop made beautiful new seats.
Mechanic installed new PowerFlow exhaust, side windows, hockey pucks, steering horn, and more.
- break -
Thursday, the aircraft had its first post-maintenance flight.  That afternoon, my mechanic and a CFI took it out for a beautiful ~30 min flight.
The 14 month old (overhauled) 80 hour 200hp IO-360 A1B motor did a great job. So did the avionics.
They both came back with great reviews and the avionics FDR showed fantastic numbers.
Three hours later, I took it out for a solo run.
Soon after takeoff, I noticed my climb performance wasn't all that great and my temps were rising. I should have turned around immediately - please believe me that I have self-roasted enough on this one. It took me maybe a full minute to decide to head back - and I didn't even take the most immediate route back, making a big fat pattern.  Again, I've roasted myself plenty so please be gentle with me... though I did at least make it back to the runway.
My climb performance, over the course of a couple of minutes, went from +250fpm to -350fpm with speeds below 100mph. My altitude capped out at 700 ft.
I'll let these Savvy charts and comment from Savvy detail the actual stats.
4 Savvy charts - 2 of the pre-incident flight, showing great numbers.  2 of the incident flight, showing nightmares.  The only difference is that the second table in the images I alternate between altitude & airspeed in one, fuel flow & fuel pressure in the other.
You'll see that the temps were basically fine while rolling down the runway... but almost immediately got out of hand in the air.
 
CHT temps ran away, likely causing the oil temp runaway, likely causing the low oil pressure.
Fuel flow wasn't amazing but it was livable. 
Manifold pressure was plenty.
 
Analysis from Savvy:
Cyls 1 & 2 suffered a pre-ignition likely detonation event from an overly lean mixture, suggest carefully checking for any debris/dirt in the #1 and #2 injectors. Max FF is a bit low but okay and likely not yet calibrated, so FF may indicate a bit lower than actual till k-Factor is properly calibrated.  

CHTs 1 & 2 above redline for 7 min peaking to CHT2 737F and CHT1 680F 
Oil temp above redline by 55F for 6 min peaking at 297F 
Oil pressure below limits for 7 min, dropping to 46 psi 
 
What the team has reported, thus far:
No intake blockage. 
No intake leaks.
No exhaust blockage.
Running the fuel pump with the injectors sticking in cups showed equal and consistent flow, indicating injector blockage unlikely.
White paper test showed no easily discernible signs of Jet A.
Exhaust tubes for cylinders 1 & 2 dyed blue from heat.
Intake tubes for 1 & 2 show heat damage near the heads.
Cylinders 1&2 show obvious signs of detonation.
Pistons 1&2 appear sand-blasted.
 
The cause itself remains unknown.  The mystery is driving me mad.  The (probable) loss of a sub-100 hour engine is driving me mad. And the flight itself attempted to kill me. 
The current plan:
 

1. Send fuel from each tank to the lab for anlysis
2. Drain the oil into a 5 gallon pail with a paint strainer or 1000 micron (or tighter) screen. Observe the debris. Observe the oil. Glittery silvery oil is typically fine aluminum and may not have damaged other components. Chunkier metal flakes are usually steel and will have damaged other engine components.  Do not discard the oil.
3. Send oil to the lab for analysis
4. Scope all 4 cylinders. Detail the condition of each cylinder, piston, valve.
5. Since there was detonation, pull connecting rods and check the bearings (start with the hottest ones). The bearing insert will tell you if there is contamination. They would be impregnated with foreign material.
6. If the bearings and oil are not a mess, discard #1 and #2 cylinders, replace.
7. If questionable, discard #1 and #2, send #3 and #4 for inspection
8. If bearings and oil look bad, send entire engine out
9. Check age and inspect interior of all fuel hoses in all areas, including from tank, connections to the transducer, fuel splitter, etc. Also check for blockage and debris.
10. Inspect inside the fuel flow divider.  We have seen debris in there that affects 2 or 3 cylinders - or sometimes just 1 cylinder but it changes cylinder from time to time.
11. Inspect fuel tanks for debris, growth, contamination, etc.
12. Inspect fuel servo.
13. Pull finger screen from servo, inspect. 
14. Inspect all screens.
15. Pull the manifold off and inspect.

Mechanic wants to do some ground runs before tearing things down.
 
I'm really upset about this.  Everything was beautiful and perfect... and just seconds into my first flight in this aircraft in months... the engine tore itself up.
The financials of this will be a significant challenge... and if we never get the root cause mystery solved, then how do I know that anything is resolved?
Just groaning out loud at this point after multiple nights of terrible sleep.

I am so sorry to hear your ordeal! Not fun…

I had a similar problem and it was timing related. I had an electroair ignition installed in my M20C, I also have the power flow exhaust.

On take off all the CHT started to rise! It was scary, I was able to keep them under 500 and landed right away.

I started to look into the issue and discovered that the timing was off on the electroair and thus the CHTs went crazy.

Hope this may help you.

Last but not least beautiful panel!

Oscar


Sent from my iPhone using Tapatalk Pro

[TheMooneyAnomaly]

6 minutes ago, TheAv8r said:

Wow… I am so sorry to hear this. This royally sucks, and I know nothing I can say will make that better. My only suggestion at this point is if the engine only had 80hrs on it and was freshly overhauled, all reputable OH shops have a warranty, you should be within that. It might be an option if nothing that was installed caused it. 

The engine shop, Tim's Aircraft Engines in California, warrantied the motor itself against workmanship issues and defects.  I had 10 days left in the warranty period (since install). This is almost definitely not that... and almost definitely an excessive lean condition caused by components outside of the motor itself

[TheMooneyAnomaly]

6 minutes ago, Oscar Avalle said:

I am so sorry to hear your ordeal! Not fun…

I had a similar problem and it was timing related. I had an electroair ignition installed in my M20C, I also have the power flow exhaust.

On take off all the CHT started to rise! It was scary, I was able to keep them under 500 and landed right away.

I started to look into the issue and discovered that the timing was off on the electroair and thus the CHTs went crazy.

Hope this may help you.

Last but not least beautiful panel!

Oscar

 

Thanks for your reply.  Glad you were able to save yourself & your engine!

[PT20J]

All the CHTs are elevated, so whatever the cause, it would be something that affects them all. The fuel flow looks about the same as the previous flight before the problem. Likely culprits would be ignition timing or fuel contamination. Cyl 1 and 2 are toast for sure. The pistons are probably damaged and those temperatures will certainly take the temper out of the rings. Detonation tends to look like sandblasting, and piston damage is mostly around the perimeter of the piston crown because the flame propagates from the spark plugs outwards and it is the end gas that detonates and creates a pressure spike near the cylinder wall before it quenches. Preignition produces higher temperatures for a longer period during each cycle and tends to melt the center of the piston crown because this part of the piston has the longest cooling path to the cooler cylinder walls.

Good job getting it back on the ground safely.

Skip

[Niko182]

I'd start with the mags. Timing could be fine but the mags could be toast. I took off one day out of truckee, and had a mag fail on me. I was lucky because it was -15c that day so the cylinder had a hard time getting hot but in a matter of 15 seconds it was about 50 to 60 degrees hotter than the rest of them. bad mag was the cause.

[ilovecornfields]

Beautiful panel. Glad you made it back safely. You’re alive and engines parts can be replaced so it certainly could have been worse.

[TheMooneyAnomaly]

25 minutes ago, PT20J said:

All the CHTs are elevated, so whatever the cause, it would be something that affects them all. The fuel flow looks about the same as the previous flight before the problem. Likely culprits would be ignition timing or fuel contamination. Cyl 1 and 2 are toast for sure. The pistons are probably damaged and those temperatures will certainly take the temper out of the rings. Detonation tends to look like sandblasting, and piston damage is mostly around the perimeter of the piston crown because the flame propagates from the spark plugs outwards and it is the end gas that detonates and creates a pressure spike near the cylinder wall before it quenches. Preignition produces higher temperatures for a longer period during each cycle and tends to melt the center of the piston crown because this part of the piston has the longest cooling path to the cooler cylinder walls.

Good job getting it back on the ground safely.

Skip

Thanks for the breakdown. 

Does fuel contamination typically mean water, low octane, and/or Jet-A mixed in? Are there other considerations?

The fuel from each wing will be sent to the lab in separate containers for separate tests.  

Forgot to mention in the post that the successful flight earlier in the day was on the right tank only, and my flight attempt was on the left tank only, switched to left immediately after engine start. I'll update the post.

[A64Pilot]

Jet-A has pretty much no Octane, Jet-A contamination is extremely likely to cause an engine to detonate, I would certainly send the fuel off for analysis.

Can you think of any way Jet could have gotten in there?

[Shadrach]

I would definitely get the fuel tested. At those temps be glad it did not hole a piston.

[PT20J]

3 hours ago, StPeteM20F said:

Thanks for the breakdown. 

Does fuel contamination typically mean water, low octane, and/or Jet-A mixed in? Are there other considerations?

The fuel from each wing will be sent to the lab in separate containers for separate tests.  

Forgot to mention in the post that the successful flight earlier in the day was on the right tank only, and my flight attempt was on the left tank only, switched to left immediately after engine start. I'll update the post.

Water will cause the engine to stop — momentarily or permanently depending on the amount — since it doesn’t burn. Jet A is the usual culprit since it will lower the octane of the fuel.

Do you know the history of the fueling for each tank? There might be some liability on the part of the fueler depending on the circumstances if the tests come back showing misfueling.

Skip

[hais]

I hope you do find the cause at least for the peace of mind and closure. I have an IO550 that detonated, root cause was not found. Your case has leads, I do hope you will confirm the culprit. 

[Ragsf15e]

Jeez, so sorry to hear this.  Don’t beat yourself up too much, stuff happens.  There were other ways you could have reacted that would have totaled the aircraft and/or the pilot but you didn’t.  You made decision that saved both.  By the time you could have turned around and flown a reasonably safe pattern, damage was done.

Please keep us in the loop.  Scary.  I gotta believe it’s jet fuel, but only in one tank? Weird.

[EricJ]

Was the aircraft re-weighed as part of the maintenance/alterations?    If so they may have drained the tanks into a storage bag/vessel/bowser and then refilled them afterward.    That could be a potential source of contamination. 

 

[TheMooneyAnomaly]

15 hours ago, A64Pilot said:

Jet-A has pretty much no Octane, Jet-A contamination is extremely likely to cause an engine to detonate, I would certainly send the fuel off for analysis.

Can you think of any way Jet could have gotten in there?

The fuel tanks were filled for fuel sender calibration a couple of months ago. No incidents on field or trouble in compass swing or prop balance runs.  6 gallon top-off morning of incident flight, allegedly to both tanks, though.  Fuel truck numbers line up for avgas but I'm asking an adjacent hangar for surveillance footage as I see they have a camera. No other incidents on field.

[TheMooneyAnomaly]

14 hours ago, PT20J said:

 

Do you know the history of the fueling for each tank? There might be some liability on the part of the fueler depending on the circumstances if the tests come back showing misfueling.

 

The fuel tanks were filled for fuel sender calibration a couple of months ago. No incidents on field or trouble in compass swing or prop balance runs.  6 gallon top-off morning of incident flight, allegedly to both tanks, though.  Fuel truck numbers line up for avgas but I'm asking an adjacent hangar for surveillance footage as I see they have a camera. No other incidents on field.

[TheMooneyAnomaly]

11 hours ago, EricJ said:

Was the aircraft re-weighed as part of the maintenance/alterations?    If so they may have drained the tanks into a storage bag/vessel/bowser and then refilled them afterward.    That could be a potential source of contamination. 

 

It was re-weighed the morning of the incident flight.  Wait, it may have been the day before. Gotta re-check fuel receipt date.  They had to add 6 gallons to top-off, so that is suspect and I'm looking for surveillance footage.

Another strange thing - the weight came out to exactly the same weight as when an alternator replaced a generator 6 years before I bought it...  which doesn't seem right.. as it should have lost 20 to 30 lbs, so maybe they had a bad weight at some point and just did math on bad numbers from that point on.

[David Lloyd]

Put some suspect fuel on a sheet of white paper. Avgas will evaporate totally.  Even a small amount of jet will leave a greasy stain. Smell the paper, jet will have a distinct odor.  Just a few minutes and you will likely confirm or dismiss the left tank fuel as being the culprit.

edit. Sorry, you said that halfway through your first post.  You provided a lot of information.

[TheMooneyAnomaly]

1 minute ago, David Lloyd said:

Put some suspect fuel on a sheet of white paper. Avgas will evaporate totally.  Even a small amount of jet will leave a greasy stain. Smell the paper, jet will have a distinct odor.  Just a few minutes and you will likely confirm or dismiss the left tank fuel as being the culprit.

We did this and the paper was residue-free  The mystery remains but fuel from each tank ships to a lab today along with oil.

[David Lloyd]

Don’t think you said, electronic ignition or mags?

[TheMooneyAnomaly]

Just now, David Lloyd said:

Don’t think you said, electronic ignition or mags?

Two mechanical mags

[Oscar Avalle]

Just now, StPeteM20F said:

Two mechanical mags

I was the one who mentioned that I had an electonic mag. Still timing issue might have been a factor 

[Shadrach]

20 minutes ago, StPeteM20F said:

We did this and the paper was residue-free  The mystery remains but fuel from each tank ships to a lab today along with oil.

Send the fuel off for analysis. There is a reason why all four cylinders were over temp. The engine had adequate fuel flow. +2° advance on one mag is unlikely to have caused the issue. Residue or no residue, something caused major disruptions to the combustion event and it does not appear to be something that was pilot induced.

[jaylw314]

I wish I could think of something useful to say that hasn't been said already.  I just went "urk" reading your account and am glad you're back on the ground safe, but horrified at your plight