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Fuel flow isn't field adjustable on an RSA injector. I've never been able to find a spec for full power fuel flow on a Lycoming IO-360-A. I have test cell data from Lycoming for my rebuilt, but they only measured airflow at full power, not fuel flow. However fuel flow was measured at three lower airflows (500, 900 and 1000 pph) and extrapolating shows that fuel flow would come out to about 17 gph at 1118.5 pph measured full throttle airflow. I got the bench test specs from Precision Airmotive for the fuel servo. Pertinent test points are at 600 and 1400 pph airflows and that works out to about 16.2 gph 1118.5 pph airflow. The Lycoming Operator's Manual shows a best power fuel flow of 15.7 gph at full power. Full rich would be greater. If I recall correctly from past posts over time, it seems most people are getting around 18 gph at full power at sea level. But I am doubtful that 1/2 a gph would account for the high CHTs.

Excellent question. I’ve read lots of different solutions. I think I used some closed cell foam (think pipe insulation) around the wire bundle on my F. Your mechanic might have different ideas. For me, closing that space changed the temperature a lot, but I wasn’t getting CO in through there. I haven’t looked there on my K yet to see what is insulating that hole, but the cockpit is definitely warmer at cold OATs than my F was, so I’m sure something is there.

It is not saying 0 PPM in the exhaust, but 0 PPM in the cabin. And running LOP you can be close to 0 PPM due to near complete combustion of the fuel, as you are running with excess O2 available.

Ahhhhh. O.K. NOW I better understand. Mooney is broke and Lasar as well as being cash challenged does not want/can't go through part approval process so needs owners to pony up cash to allow that to happen or Mooney goes bankrupt and existing owners lose equity and the liklihood of someone coming in buying Mooney and jacking up prices (more than current out of this world price) will happen...OR an existing specialist in aviation parts buys Mooney and organizes as a PARTS supplier vs. trying to build and sell airplanes under current type certificate (that is unprofitable) as shown by bankruptcy after bankruptcy.

I have heard of oil coolers being hooked up backwards and causing issues.

I certainly wont rule out an induction leak, however I always thought that an induction leak would lead to a rough running idle? This engine runs as smoothly at idle as any IO-360 I've ever flow, for what its worth. My left cowl flap is flat, I will double check the rigging. I know the right side is about 1/2" open when close, but I don't remember if the left one is as well.

I think this was mentioned earlier in the thread, but does anyone know how the Assurance program would affect the MSC network? I'd prefer more, not fewer, MSCs, and the Assurance parts priority thing is a little bit hard for me to get my head around. When I'm placing an order for a factory part but the order is submitted from my mx shop, I assume that Mooney has no idea who the ultimate buyer is.

Fuel flow looks a bit low. Rule of thumb is WOT, full right, 1 GPH per 10 HP. So 200 HP engine should be 20 GPH or higher.

What do you seal that with?

Which is downright confusing to normal people and makes little sense. And will lead to issues with people flying aircraft they are not authorized to fly. Pilot A has a Sport Pilot certificate, so he can fly that M20J, but NOT that Model XYZ Light Sport airplane.

MAP would still be less than ambient pressure at sea level, no? Granted not by much, but 4" of pressure difference is enough perhaps for what he is seeing. No? This is curious: FF decreases while EGTs rise twice when I presume power was reduced. Classic induction leak? Also the small rises and drops in EGT could be going so lean that it's over the top and to the lean of peak side.

As I understand it, they are buying all of Mooney. They need to keep the Mooney name and location to keep the legal ability to make the parts under the existing approvals.

Bendix never made a dual mag with a lower lag angle for the impulse coupling, so if you set the timing to 20, it will fire 5 deg late during start.

You might check the Surefly timing. Sureflys are timed to 0 TDC on the engine and the advance is set with dip switches. There have been instances of mechanics timing them to 20. You might also try setting the Surefly to fixed timing as a test.

Own all of Mooney or part of Mooney? It's hard to understand how the membership program will work. It seems if you're AOG, you could just pay the membership to jump ahead of the line of the non-members and cancel. You may as well call it a rush fee.

OK, well the Surefly installation muddies the water a bit.

When you check the baffle seals, make sure that after flight they are curved inward. If not installed correctly, they can look fine when the cowling is installed but then blow back from air pressure causing a leak. Afterwards, they can appear to seal the cowling when the engine isn’t running. Another trick to check for air leaks is to put the airplane in a dark hangar and insert a light through the oil filler door and peer through the inlets by the spinner. A significant induction leak should cause a rough idle. For comparison, my IO-360-A3B6 in a 1994 J generally runs about 360 deg F CHT or less with cowl flaps open during a sea level climb at 105 KIAS with full rich mixture and about 18 gph fuel flow. It will get hotter on a warm day at lower IAS but never over 400. In cruise I usually see about 340 with the mixture leaned peak or LOP and the cowl flaps closed. If your left cowl flap is flat rather than curved like the right one, you might try rigging it to be open about half an inch when the cowl flaps are closed.

At closed throttle, high vacuum scenarios, yes. In climb at wide open throttle, an intake leak isn’t going to have much of an effect on mixture unless the leak is huge.

Whoops…misfire on my part. My apologies! I know that you’ve received a lot of Lycoming specific information from the factory over the years. I have never timed a dual mag. Do you have any insights as to why the optional 20° timing is prohibited with D suffix engines? Having flow behind my engine when times at both 20 and 25°, I prefer 25°.

Thanks so far, I will double check the rear baffling seal. The magneto is times to 20 degrees, though I also have a SureFly ignition on the left side that is set to the variable timing option. This is the flight in which I had some engine roughness and CHT #3 tended to have a mind of its own, pulled the cylinder after this flight: https://apps.savvyaviation.com/flights/shared/flight/9962458/5b23d3f3-71e9-4feb-ac34-01b25341f1dd This is a break-in flight where CHT 3 rapidly reaches 440: https://apps.savvyaviation.com/flights/shared/flight/10132193/0238ab27-4e50-41be-a418-cc720035a6eb I have not run a test profile yet, as I'm not able to climb about 1000' without the CHT continuing to rise. -Jared

OP said he has a A3B6.

An induction leak would present itself as overly lean condition. I just had all my induction gaskets and hoses replaced on a 18 year old engine and they were all brittle and destroyed. There was evidence of AVGAS on the induction pipes (with a turbo the leak happens both ways at different phases of flight). With your NA engine it would happen only to the lean direction, so you wouldn't see any traces of AVGAS.

Your point?

Check rear baffle seal about half way across the engine. They have a tendency to droop there and let air escape vs being forced down thru the cylinder cooling fins Look at the baffle seal for evidence of contact with the cowl and maybe use a light at night to check for fenstration

I seriously doubt that this is a timing issue. I run maximum advance in my engine for the TCDS and it runs much cooler than yours. I would start by thoroughly inspecting all baffle material. Do not neglect to check the internal baffle seals in between the cylinders. With a relatively new installation, there can be multiple factors that are causing problems. Indeed, you could have a baffle seal issue and also if you flow issue. I’m of the opinion that 17.5 GPH is not adequate full rich fuel flow for an IO360 departing a sea level airport. Your fuel servo may need to be serviced.