Shadrach

Right, practically speaking is upper deck pressure not a proxy for airflow?

I would say that the vast majority of mechanics know very little about engine operations. I don’t know the percentage of operations knowledgeable mechanics but I’d bet it barely cracks double digits… and almost all of those are likely operators in addition to being mechanics

No need to yell…

No. It means that wherever the red knob is set, the servo will attempt to, more or less, maintain the the set F/A ratio. As an example if you’re at 18,000 feet set at 16.5gph and 26”, and the turbo plumbing fails rendering the engine without boost, the fuel system is not going to continue flowing at 16.5. It will reduce fuel flow based on the now much lower metered airflow.

Who are the idiots to which you are referring? This site is full of individuals with differing opinions. I’ve come across a lot of statements with which I staunchly disagree, but I’ve encountered very few idiots here. It’s not a term I use lightly. The vast majority of the forum members base their opinions on publications they’ve read, the data in the publication used to support the statements made and the ability to reproduce similar outcomes in the field. Trust in an institution is built or destroyed incrementally over time. Lycoming has not always put their best foot forward. I’m old enough to remember Lycoming’s “experts are everywhere memo” that used to be located at the address below on Lycoming’s website (the link below is long since dead): https://www.lycoming.com/support/troubleshooting/resources/SSP700A.pdf It did not name names, but was an obvious direct shot at GAMI, APS and other heretics in the industry. I was actually embarrassed for the author as I read it. Given that it was likely written by an engineer at Lycoming, I rationalized what I was reading by imagining that the legal department held a gun to his head while he was typing. It was indeed idiotic to anyone with an understanding of how mixture works. I think it’s important to take a manufacture’s recommendations seriously. I also understand that in a small, highly regulated and highly litigious market there is very little incentive to course correct on past statements. Given how slow the manufactures are to move, there has been sort of a small cottage industry of companies that have helped take GA into more modern and data driven operations. Lycoming facetiously called them “experts”. Those small companies and their executives have dramatically changed how much information and understanding the general pilot population has about combustion science and applied power plant operations, among other accomplishments. What is mostly mainstream now was controversial at Lycoming in the early aughts which is why the memo was released. At some point Lycoming realized how bad it had aged as it was removed. The Part number SSP700A is no longer available on the website. George Brawly having a sense of humor posed for the attached pic in front of a Lycoming trade show booth. I’ve updated it just for you. Back to shock cooling or sudden cooling or whatever you want to call it. Perhaps it is real, but no one with the ability to do so has been able to generate data to support its detrimental effects. The “Idiots” that have stated that shock cooling is or probably is a myth include but are not limited to: George Braly John Deakin (RIP) Walter Atkinson (RIP) Rick Durden Mike Busch and many others…

I’m not a turbo operator (at least not in the air). My assumption was the that the fuel servo would adjust for changes in MP and hold roughly the same air fue ratio based on the mass of the airflow entering the servo. That’s certainly how the RSA system on Lycomings work. They won’t hold an exact F/A mixture across a broad range of airflow, but I cat imagine it being so far off as to not support combustion

I would think the servo would compensate for the reduced manifold pressure.

Indeed it does not. As far as I know, none of the NA planes have such a warning in their POH

I’m pretty sure there are several NA Mooneys that have been well above 20K. @Immelman Perhaps there are aspects of the turbo that make a restart more challenging.

Something else that has been helpful to me is a hand vacuum (Mighty Vac) to help evacuate any remaining air from the system.

I use a Motive pressure bleeder. It’s a tight space. I push a piece of vinyl tubing over the fitting. The ID of the vinyl that fits over the fitting is the same size as the OD of the vinyl tube that comes on the pressure pot. They can be connected with hose clamps. Not ideal, but it works. https://www.amazon.com/Motive-Products-100-System-Bleeder/dp/B00CJ5DV2I/ref=asc_df_B00CJ5DV2I/?tag=hyprod-20&linkCode=df0&hvadid=312634019511&hvpos=&hvnetw=g&hvrand=10477568999880027208&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=9008066&hvtargid=pla-568407457373&psc=1&mcid=c4ffda30e4823882ae1c476d60c4cbc0&gclid=CjwKCAiAlcyuBhBnEiwAOGZ2S-BQBFgcM90SYVET7fWbmM4qMVpTOWv6l3u1hp94rU-M2WqS18nulBoCct4QAvD_BwE

I took it as a good natured jab at the high empty weights and lowish useful loads of some of the long bodies.

Having just gone through an issue with faulty reading, I don’t think the thermocouple has failed, but worth checking. Problems can be caused by maintenance, but they are normally binary (it works or it doesn’t). I cannot envision a maintenance induced issue that causes it to read 60° high. I would expect increased oil burn at those temps and a decrease in oil pressure. No chance that you winterized the cooler earlier in the season and then went flying on an unseasonably warm winter day?

My cylinders are never really hot. It’d be pretty hard to shock cool something that’s already cool (relatively speaking). My cylinders (as with most) experience more rapid temperature changes on start up. Greatful that shock heating isn’t a thing.

I don’t throttle back unless it’s bumpy. CHTs in the high 200s aren’t reall a concern. #1 and #4 are under 300 this time a year in cruise. Been that way since I started flying it 20 years ago.

The discussion was around what the engine was designed to run on which I believe was the long since discontinued 100/130. That’s why I am surprised they’re loading up on 100LL

Yea, that was my point. 100/130 has double the TEL. I was looking at the And according to the Lycoming TCDS (E286) I was referencing, the 8.5:1CR engines have a min grade of 100/130. There are no Mooney serial numbers in Lycoming’s TCDS. I will give it another look to verify I did not misread anything.

For the 64gal tanks it’s closer to 10 gallons before fuel is visible through the filler. In terms of a starvation incident for a given amount of fuel, I would think that descent to landing would be the attitude with the greatest chance of unporting a low tank.

But he’s not in different leaning phases. He has the manifold pressure and prop set for 80% power and full Rich Per the POH. So either his fuel flow reading is wrong or the carb is running lean

I don’t even think 91/96 was a thing when they were designed. TCDS says min grade of 100/100LL for all 180hp 8.5:1cr O360s. The lower horsepower O360s (168hp) with 7.2:1cr were 80/87.

Does that look like it’s from wear and tear or installation by someone who should be banned from touching a soldering iron? I recently repaired the connections in my factory oil temp probe and I was trying figure out if the connections deteriorated or were poorly constructed. It’s likely a 57 year old part, but the wires are definitely not.

My idol set on the low side (~500rpm) to minimize landing distances. In terms of ground ops, I think any 4cyl Lycoming should be operated at 900 or above.

Makes me wonder what’s going on with some these O360s. They were designed to run on 100/130 which had almost ~twice the amount of TEL as 100LL. I asked my dad about ground leaning and plug fowling in the O360s he ooperated in the 60s (M20C and Comanche 180). Ground leaning was was not a thing back then and plug fouling was not common in the higher compression engines designed for 100/130.

As configured, I agree. The Screw jacks I once had access to had a ~16” handle on a two way ratcheting cuff. It was actually easing than actuating a hydraulic piston, but did require more movement.

My dad had no problem with the J bar well into his 80s. I’ve not had him fly left seat in a while, but I doubt much has changed at 85. He bought his first Mooney in 1963 so he has 60 years of muscle memory going for him.