The down side of partnerships

[marky_24]

I'm in a 3 person partnership on a 201, today after my flight i downloaded the data from our JPI 730. Only to see this: 

 

https://www.savvyanalysis.com/flight/487497/99090076-8d55-4142-b114-085579357b64

 

https://www.savvyanalysis.com/flight/487500/461544be-bee8-4d68-a638-5d0274ba4dbb

 

 

 

It was flagged for a high CHT. looking at the fuel flows on take off, a partner took off with 13.5 GPH!! I found 2 other flights where it was around 10 GPH!!!!! Mind you this is on our 50 hour SMOH engine that ran us $32000 to rebuild and hang!!! 

 

How much damage do you think this is doing/done all ready? I have tried and tried to teach him how to manage the engine, but it doesn't seem to sink in. 

[jetdriven]

Sounds like he is taking off with the mixture leaned for ground ops. I'd remind him again and suggest that any engine damage comes from his end. 4 new jugs and labor is ~13K

[MB65E]

Well, I wouldn't want him to continue operating like that. Tell him to leave it in all the way and not touch it!! Prolonged temps at those recorded could be bad. I don't think it did any damage during those flights. Under 500dF shouldn't do any damage. Your redline on your instrument is set at 400. That is lower than the lycomings 500dF limit. At least you know what's going on!

I lean on the ground untill the engine almost quits. Any advance in throttle and the engine quits or stumbles. Preventing Takoff and preventing cooking anything.

Good Luck!

Matt

[marky_24]

Yes I set the limit at 400 Based on Mike Bush's webinar . I'm just worried about donation, and burnt exhaust valves running that lean at full power. I hope no damage has been done all ready.

[cbarry]

Why don't the two you go fly to get lunch. You fly one leg and him the other and you can readily trouble shoot engine management habits and have a great time while your at it.

[N601RX]

Does the 730 have a remote bright red flashing annunciation light right in front of the pilot? If not put one there and the bump the limits down 25 deg from the level you really want.

[Bob_Belville]

You may have a broader issue with your partner. It would seem he does not use a checklist which certainly includes mix full prior to take off. Failure to use checklists in a complex aircraft is not good practice. 

[jetdriven]

Those temperatures aren't high at all.  Your alarm threshold is too low. 

 

My CHT peaks at 450 - 475 degrees EVERY time I take off at full rich setting, and the only way to counteract that is to reduce power and lower the nose for 125-130 mph climb.  My cht's at takeoff may be high by some expert viewpoints, but are still comfortably within the Lycoming operational manual specifications of 500 degrees.

 

In fact, my engine cruises at your partner's indicated average peak takeoff temps all day long with my mixture set properly at a fat fuel guzzling 150-200 degrees ROP. 

 

He operates above 400 degrees for a negligible ten seconds which is even less reason to worry.  Overall long term temperature operations are perfect.  I would worry only if he had high continuous operational temperatures in cruise which would indicate poor fuel management or bad baffles..  Appears to be neither.  I wouldn't worry about it.

Yeah but he has a J model, which this time of year won't exceed 300-330 on takeoff. The risk isn't high CHT, it's rapid heating, piston scuffing, and detonation from taking off at best power mixture or a little leaner. Fuel flow should be around 17 GPH for good cooling.

[John Pleisse]

It really depends on what is going on in your partnership. Is he derelict and doesn't know what he is doing, or is he intentionally pushing it to save fuel? Both are problematic.

 

pmccand, what type Mooney are you flying? That's excessive and unnecessary (norm asp), unless you live in Mohavie, Phoenix or Las Vegas. Why not just fly at 499 CHT? I don't hit anything above 450 with the cowl flaps closed in 110 degree summer heat, never reach those temps (201).

[Bob_Belville]

I was concerned that my FF was a little low and I was anxious to see what it would be after the engine teardown. I am pleased to report that initial FF out of two near sea level fields during the ferry flight home was 18.3. Even at my field (1270') I was showing 18.0 until I was climbing through 1800'. 

[jetdriven]

I have a friend with an O-360 M20G and it runs 400 in cruise all the time and it has 1900 hours on it. No cylinders have been changed. I think parallel valve cylinders do run hotter because of the smaller fin area and they also tend to handle it pretty well. Likely because of the engine's lower output and cylinder pressure.

#3 and #4 flirt with 390 in cruise sometimes and after fooling with it I decided to live with it. But I never see over 330 on takeoff, and I wait until I see 275-300 before going.

[midlifeflyer]

This is definitely a "talk to" event. If the problem persists, what does your group's operating agreement or rules say about it?

[chrisk]

Why don't the two you go fly to get lunch. You fly one leg and him the other and you can readily trouble shoot engine management habits and have a great time while your at it.

Bingo.

[John Pleisse]

M20B carbed O-360 A1A. .................. B models run consistently at 390-420 degrees on Cyl #3 in cruise and takeoff at 425-450. That's exactly what I get, so, the best action I take is to lower my blood pressure, fly it by the book, within recommendations and just don't worry about it. 

 

Is this just more common on carbureted Pre J models? Cowl, baffling and carb mixture culprits?

[Bob - S50]

If in doubt, ask Mike Busch, but here is my ...opinion...

 

1.  CHT's and EGT's did not get that high, and EGT's don't really matter anyway.

2.  Both times it looks like the engine was nicely warmed before takeoff since the CHT's were over/around 300F so I would not think rapid warm up would be a problem.

3.  Since you operate out of SGU and the field elevation is almost 3000', I would think a fuel flow as low as 16.5 GPH would be normal/acceptable (but still higher than he had).  If he does that at sea level the results could be totally different.

4.  At 3000', you can only generate about 90% of rated power anyway so altitude gives you some protection.

5.  I believe burnt valves are usually a result of poorly seated valves, and power setting should not affect that.

 

6.  However, running lean like that would tend to cause peak pressure to occur closer to TDC and put more stress on the pistons/rods/bearings.  However, CHT is supposed to be our best indicator of peak pressure and the CHT's, again, did not get that high.

 

With that said...

 

1.  I agree with you, regardless of what others say.  We have our JPI set to alarm at a CHT of 400F, and I try to keep it under 380F.  I wouldn't want to operate a car engine at red line RPM and I don't want to operate my Mooney engine near red line CHT either.

2.  I would ask him what the hell he is thinking?  Maybe he has a good reason for it (doubt it).  Maybe he isn't using full power for takeoff (dumb).

3.  Unless he can convince you he has a good reason for doing that, slap him up side the head.  Depending on how your partnership is set up, get the other partner to join with you and implement a penalty plan.  Anybody who takes off with less than XX GPH fuel flow owes $XXX to the engine fund on top of any other charges.  If the engine gets trashed on a particular flight, and it is found the FF was low, that person will pay for any and all repair work.  Nothing talks like money.

4.  It also looks like he does not know how to use the vernier on the mixture.  All his fuel flow changes come in big discrete jumps like he is pushing/pulling the mixture rather than screwing it in and out.  How old is this partner?  Too old to learn new tricks?

5.  Maybe you and the other partner can force him to get some dual with you two or a CFI with emphasis on (as mentioned by others) a flow/checklist, especially to include mixture setting prior to takeoff.

 

While I've got lots of hours, I'm still relatively new to GA flying and trying to develop my own flows.  I'm trying to use:

 

1-2-2-2 for takeoff: 1 = fuel tank selected that has enough fuel.  Move up to 2 = Trim and Flaps set.  Move up again to 2 = Mixture and Prop set.  Move over to 2 = Lights and Boost pump on.  THEN I can push the power up for takeoff.

 

G F P after takeoff.  Gear up.  Flaps up.  Pump off.

 

GG FF PP for landing (as opposed to GUMPS or GUMPF).  Gas (fuel tank), Gear (down), Flaps (set), Fuel (mixture set), Prop (full forward), Pump (on).

 

Good luck,

 

Bob

[jetdriven]

They also recommend for long engine life 65% power or less and 360 CHT or less. Maybe 400 can't read it right now.

[carusoam]

Great communication skills with your partner will always help.

Bring your data and checklists to lunch.

This is more human interaction than anything else.

You have a great amount of data that you can share.

My C had 1 CHT and no FF. I would have needed a partner add a JPI for that!

Best regards and good team work,

-a-

[marky_24]

I am the maintenance manager of the group, when we got the engine overhauled I talked them into a 730 so we can keep this engine alive for a long time. At that time we had a group meeting and all sat down and watched Mike bush's webinar on engine monitors. Its chocked full of very useful information  about how the tensile strength of aluminum goes down over 400 degrees, how to do a run up with them and so on. After the video we discussed how to operate our plane. Start the engine, check for oil pressure, then lean for ground opps. Then how in to summer  we have to lean for takeoff as our DA is around 5-6000 most days. I think he must be getting confused between leaning for ground opps and take off. I have had this discussion before with him, and i even moved the GPH to the top left of the parameters on the 730 display so its easy to check on take off roll. He does see the 730 flashing CHT overtemp and oddly enough he does react to that properly, increasing mixture and lowering the nose. Im just hoping that no damage has occurred yet, like a burnt valve or something along those lines. 

[BigTex]

Strickly my 2 cents but it sounds like everyone needs to set down and talk through all of this angst.  Discussing it on the message board isn't the place to work through issues with other partners... Again, my two cents.

[bnicolette]

Does it look like the #3 valve is sticking during power off for landing?

 

It does look like when he catches the alert flashing that he rolls in the mixture?  Maybe it's better to teach him the target EGT method (which for me generally was about 1250) once you finally get him to richen the mixture for takeoff.  

 

Definitely need to address it though.  Good luck.

 

My FF was generally 18.3 during takeoff. 

[Marauder]

My FF was generally 18.3 during takeoff.

Good thing you used the operative word "was". Have I helped with your seller's remorse yet? Hope this doesn't hurt my chance of riding shotgun in your Baron.

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[marky_24]

Your right I didn't mean for this to sound like a bashing of the partner. I was just venting about a band new engine was being flown this way and to ask if there was potential for damage to have all ready occurred. He is a really good partner other than this one issue,albeit a large issue $$$

[BigTex]

Your right I didn't mean for this to sound like a bashing of the partner. I was just venting about a band new engine was being flown this way and to ask if there was potential for damage to have all ready occurred. He is a really good partner other than this one issue,albeit a large issue $$$

 Go fly with him...

[bnicolette]

Good thing you used the operative word "was". Have I helped with your seller's remorse yet? Hope this doesn't hurt my chance of riding shotgun in your Baron.

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I know really and that was a takeoff flow.  Won't it be great to see 28 per side.       

[Marauder]

I know really and that was a takeoff flow. Won't it be great to see 28 per side.

I got an idea. When you talk about your old Mooney flow rates, use pounds per hour and when you are talking Baronese, use gallons per hour. You'll feel better. At least until the credit card bill shows up... Sorry for the highjack Marky. I find it hard not to kick an ex-Mooney owner when he is in seller's remorse! Sent using Tapatalk