Shadrach

George ran it on a single point of ignition which is operationally similar to retarding the timing 5°. That eliminated all traces of detonation. He theorize that the UND fleet could have avoided the detonation issues by retiming the engines closer to 20°.

Im pretty close to that. I usually add three over a 50hr interval and it’s ready for a fourth at oil change.

What oil level are you trying to maintain? A qt every 8 to 10 hours is pretty reasonable.

And also a DER with an Undergraduate from Brown in Aeronautical Engineering. I’m not some fanboy, sycophant but you seem to be going out of your way to downplay the significant work he’s done in many areas of GA. I also appreciate that he’s thoughtfully responded to every email I’ve ever sent to him and we’ve never met nor done business in any way. So, I’d say he’s fundamentally a responsive, generous, repository of knowledge in addition to being a “salesman” and an attorney. Not sure if you have an axe to grind, but it kind of comes off that way.

Yes, a salesman that is an IA, A&P, ATP, DER and propulsion engineer. It’s certainly in his sales interest to get up at Oshkosh in front of the whole Aviation community and bullshit is way through a presentation with biased data. Did you watch it? I’m not saying that he doesn’t have a vested interest G1000UL, but the collected data is pretty compelling. When you can sample detonation traces in milliseconds, and have the ability to switch between three different fuels without changing any other parameters, and one of those fuels clearly induces detonation, it’s kind of hard to blame the messenger. So either he cooked the data, or the engine parameters that he said he ran were falsified in order to induce detonation or perhaps, just maybe, 94 UL has fallen short of its goals. I’d much prefer it if there were an independent third-party with a sophisticated test stand. Then the FAA wouldn’t have to rely on an interested party to test someone else’s fuel for free.

This was an interesting watch for sure. George, as usual is armed with lots data. The data show that swift fuel does not meet FAA detonation margin standards when operated at normal power settings in 25° high compression (8.5:1, 8.75:1), engines on the test stand. I was listening to the presentation in the background while working, but my take is that the data suggest that the valve recession discovered in the UND trial was likely caused by shockwaves in the combustion chamber due to the engines operating in light to moderate detonation for extended periods of time. GAMI also had a number of solenoids malfunction on their test stand after running Swift UL94. The rubber diaphragms became brittle and failed. The solenoids had been in service for 24 years and all of the failures occurred within hours of being exposed to 94UL. The Q and A was a bit heated as the Swift Fuel folks were in attendance and naturally were not happy with the findings. George brought a piston along from one of the engines showcasing the effects of running on 94UL. Additionally, GAMI's STC is now available. The cost is $50 plus $1.75 per horsepower ($400 for a 200hp Lycoming). When G1000UL will actually be available is anyone's guess.

Hot off the presses! less than an hour old...

I expect the @TheAv8r had the same experience whether he recognized it or not.

This^^^^ I would add that damage history in the logs and damage history in reality are not the same thing on a 45 year old airplane. In my opinion GA was a lot more cavalier pre Y2K...the further back, the more cavalier. Things happened and things were repaired, some of it logged and some of it not. There weren't high def cameras in everyone's hands and on buildings until fairly recently. The "Range" is under full time surveillance now and cowboys get caught..

Wow...200hrs to establish oil control...? Can you imagine? Your response should have been so I need to run 70% or more for the next two years and or 10% of TBO while limiting ground ops and no pattern work? No cylinder should take 200hrs to break in. Chrome is the hardest and takes the longest at ~25-30hrs. Nickel cylinders typically break in faster than steel and steel should be all done between 5 and 10 hours. I guess one of the benefits of hiring ignorant reps is that they don't now when they're shoveling BS...

Understood... I have spent too much time reading the Precision Aeromotive training manual and have sort of developed my procedure based on my understanding of how the system functions. There are more than a few ways to skin this cat. Just sharing mine. The POH (see below) does suggest to go to ICO before turning the pump off. 10. Turn boost pump on and note fuel pressure indication. 11. Move mixture to full rich (forward) position for three seconds and return to idle cut- off (aft). Do not keep the mixture control in the full rich position more than a few seconds with the boost pump on to avoid flooding the engine

It does not take much throttle movement for the system to allow good fuel flow for prime. However, I too prime with both knobs forward. I try to eliminate ambiguity and create precise and repeatable procedures. It helps to eliminate guess work when trouble shooting.

I've made some notes above. I think that your procedure would benefit from some modifications and reordering of steps Try the following and see how it works: Throttle open 1/4 mixture rich fuel pump on until fuel pressure needle maxes out plus an extra few seconds (add a few more seconds in cold weather). Mixture to idle cut off fuel pump off throttle to 1000 rpm (approx) engage starter Little to no fuel is being pushed passed the flow divider and into the injector lines until until the system builds sufficient pressure (~4psi) to unseat the valve in the flow divider. I start my prime count AFTER the system has pressurized. Usually two to three seconds. Some boost pumps are healthier than others. I had to shorten my prime interval after Aeromotors rebuilt my Dukes pump. You will have to figure out what is ideal. If you hear exhaust "after fire" on start up, subtract a second or two for the next time. Also, do verify that the system holds pressure after going to idle cut off. Your previous method of shutting the pump off before going mixture lean likely allows for a loss of pressure (aft of the flow divider) in the time it takes to pull the knob to ICO. When I prime, I always ensure that I "lock" (mixture to ICO) the system at max attainable pressure before starting. This ensures that the cylinder intake manifolds have been primed and that the rest of the system is primed and ready to deliver fuel immediately upon enrichening the mixture. Will it make a huge difference? Maybe not, but It is best practice avoid "slack" in the system. My IO360 typically cold starts like someone took their finger off the prop of a Guillows balsa wood model with a double knotted rubber band. Which is to say that more often than not it fires on the first compression stroke. When it doesn't, it's usually during the transition from fall to winter when I tend to under prime on the first few cold days.

I have not flooded an engine in well over a decade. If I did it now, I am sure that I would likely pooch the procedure. Sometimes the best course of action is to walk away for a while if time permits.

The only reason I can think of to crank with the throttle wide open is when trying to evacuate fuel from fuel saturated engine.

I cannot fathom electing to fly up a box canyon...into rising terrain...towards a ridgeline in excess of 9000'msl...in August! The DA at his departure airport (4200msl) was ~6300'. He was loaded with 3 adults and two kids, plus bags and fuel. I am sure they were on the heavy side. He could have easily stayed West of the ridge and out of the canyon while attempting to gain sufficient altitude before turning East. Moronic decision making...

Nevertheless, it appears he’s still flying.

I’d estimate a range of 4 to 12 blades. It’s hard to say exactly because conditions vary and the state of the fuel in the lines after shutdown is dynamic. The burbling and sucking sounds you hear when putting the plane away is fuel expanding out of the injector lines and into the intake manifold. So, while I can’t say exactly how many blades it should take to fire off when hot, I can say that it’s prudent not to add fuel to the situation until you’ve verified that it is required. There are times when I have been slow on the mixture and failed to deliver fuel in time to keep the engine running after it has fired. When that happens you have two choices, a short, maybe 3 second prime or alternatively, you can crank and start feeding the mixture in (boost pump off) until it fires. I’ve used both with good success.

I’m pretty sure it was because the author,@1980Mooney elected to delete it. The author of a thread can delete it at any time.

Smirking at a self inflicted wound is inhumane. Like many problems in Aviation, the source is usually the soft, squishy bit behind the yoke. An IO360 will start just fine when hot by simply turning the key until it fires and enriching the mixture. The problem is most pilots new to the system are suspect of something so simple. They feel compelled to do something more to “help”. When that doesn’t work, they grab the shovel and really get to digging.

It does not happen often, but it does happen. Context is rarely offered for the deletion of threads or individual posts. It is almost always driven by a complaint from a form member.

That’s an interesting if not dated write up. I wonder how many 231 owners are willing to run their engines at 2500, 31’ and 50° rich of peak TIT? Another curiosity are M20J power numbers in the test vs the POH for the IO360 in my M20F. According to my POH 7500’ - 2500rpm, max power = 76%. 10,000’ - 2500rpm, max = 70% Yet in the test, the M20J shows 64% and 60% at those altitudes.

30 years earlier, he flew a Cherokee 6 into a box canyon with rising terrain. He flew the plane into the ground but he and his four passengers survived with minor injuries. His poor judgement has injured 5 people in his flying career. He’s very lucky, it’d be best for everyone if he stepped away from airplanes whether voluntarily or otherwise.

The POH for my F model shows max power at 7500’ at 83% and 77% at 10,000. I have never flown a 231. However, I did take off behind a very nice looking example last year. My box stock F model was at least 10kts faster at the same ROC. I thought I was imagining it as he became larger in my windscreen. About that time, tower called me to verify that I still had a visual as they had gotten a collision alert. I jogged to the right and increased pitch a bit. I passed him about 6 miles from the runway and 500’ above him when he turned south at the VOR. I have no idea what climb power setting he was using, but am sure it was conservative. K models do have more cooling drag than their normally aspirated brethren.

Given that he’s an IA based just south of the accident location and is likely plugged into the local GA mx community, it’s likely that he has additional info that is not included in the preliminary report. For instance, he seems to know that the plane had an in flight power failure days before accident. Also, I’m pretty sure that @philiplane is a fan of Surefly products though perhaps not in the dual configuration.