Shadrach

I verify continuity for both tanks before takeoff. I don’t go crazy worrying about which one has more fuel unless there’s a serious imbalance. If there is an issue, you’re likely to find out well ahead of being airborne. At taxi power, my IO360 will starve about eight seconds after the selector is moved to the off position. However, Trying to pull fuel from a closed valve is not the same thing as pulling air from an unported tank. One of my tanks is empty right now for sump valve replacement. I’ll try to get some data on how long it will run when switched from tank with gas to tank with no gas After I finish the annual.

I discussion was around @donkaye’s comment that he does not run LOP because he does not like the speed/power loss. There should not really be a speed/power loss. One just needs more manifold pressure to run a higher ff while lop to get back the extra speed.

That is a big CHT spread. Was it running smoothly? I have a hard time believing that an 85° delta is accounted for by cooling airflow variance alone. Seems to me those cylinders were at significantly different power settings (FF).

Why you do that? LOP to much leaner than peak? We were talking about speed/power loss going from ROP to LOP. I don’t have a Bravo power chart in front of me but if I did, I could easily calculate the approximate LOP FF that would yield the same speed. Power would be the same, FF would be less and CHTs would likely be lower as well. The down side is that TIT would be closer to redline.

I have a feeling that’s because he has verified his preferred FF settings are in his comfort zone with regards to the mixture spectrum. Sooo, it would be more fair to say he doesn’t bother to look EGT now. That does not mean that he never has.

Freeway airport off Rt 50 on the MD Eastern shore. Image is from google streets. When I drove by this summer, the make shift cover for the baggage compartment was missing and completely open to the elements.…

Look at his data. They don’t run that hot. His fuel flow is clearly set on the low side. I think a large portion of his problems disappear by increasing fuel flow by 2 gph

Even your pre prop strike numbers were on the hot side. You need 29.5gph for take off. Start there.

All of your CHTs look elevated to me. What is take off fuel flow? Looking at your July flight, your full rich max power EGTs are 100-150° Higher than mine. Things look better in September, but more fuel would likely help. I suspect there is an issue with baffle install. Do you have any pre prop strike data?

When operating the engine at a mixture setting with a surplus of fuel (ROP), power is determined by mass air flow. This is because that surplus fuel is not being converted to power. When operating at a mixture setting with a surplus of air, power can be determined by fuel flow because all of the fuel is being used to make power. 65% power is 65% power no matter which side of peak the engine is set. The problem is that it requires more manifold pressure to run 65% LOP than 65% ROP. That situation is correctable with a turbo. It is not correctable with a f normally aspirated engine once the throttle is wide open.

If you have a turbo that runs well on the lean side of peak, there should not be a speed reduction. Just an increase of a few inches of MP. There must be another limiting factor.

You either have insufficient cooling airflow, excessive internal cylinder pressure (mixture,timing, etc) or both. It looks as though that, for the most part, you’ve eliminated fuel delivery as a potential problem. If this we’re a timing issue, the problem would very likely manifest across all cylinders. So an airflow issue seems most likely. In rare cases, exhaust leaks can blast a cht probe and cause false readings. Are all other CHTs in the normal range? Are you able to upload engine monitor data? Have you thoroughly examined the internal cylinder baffles?

So it reads to me like you need to find your GAMI spread as a starting point. You stated before that the engine gets rough well before TIT redline. Does your TIT peak and drop off before roughness? I’m sure Paul will be a great resource.

Do all of the Bravos need GAMIs to run power settings on the lean side? This thread interests me. It seems to me that TIT redline is more centered on Turbo longevity, not cylinder longevity. I see that everyone is advocating for using TIT to set power. I understand why. On the rich side of peak, cylinder to cylinder power variation is minimal even with cylinder to cylinder mixture differences as much as 50-150 degrees from peak. However, in a perfect world, would it not be better to be aware of both EGT and TIT? Would it not be better to set power with EGT as long as the setting results in a reasonable TIT number.

Basically it’s a way to share the aircraft as well as the costs without giving up controlling equity in the plane. AOPA would be helpful in this area. Worth giving them a call or searching the site.

Partnerships can make a lot of sense, but they are like any other relationship. The parties need to be compatible and have communicative. It's taken a few years to get here but we have a well balanced partnership with little in the way of surprises. My partner flies professionally but only uses the Mooney 20-30hrs a year. I am very hands on which reduces both our fixed and variable maintenance costs by quite a bit. His benefit is that he pays quite a bit less than half of what it would cost him to keep and maintain a Mooney by himself for the small amount of flying he does. My benefit is that I have what feels like unlimited access to my plane but get half of the bills covered. It's a win win for both of us. You might dip your toes in with a non-equity partnership. Most of the benefits that you're seeking without the hassle of property changing hands.

Many shops used to do field overhauls and repairs of both engines and mags. There are still several A&Ps on my field that will repair mags. I am grateful to one of them that helped me avoid scrubbing a trip by replacing a bad coil same day.

There is usually a decent selection for sale on eBay.

Cabin leaks or no leaks, if he has the same set up that I have in my 67, he should have very high temp at the vent. Depending on mixture setting, mine measured between 155° and 175° at an OAT of 7°. At merely freezing OATs it’s pushing close to 200°. There is no ambiguity in whether or not the system is working properly…if it is, you can hard cook an egg with it.

I agree something broke it. However, given what I know about the construction of the Mooney airframe, it seems highly unlikely this was transmitted through the steel frame to non structural aluminum sheets then through the retainers and the adhesive to the plexiglass. I don’t believe it likely that it was airframe “flex” from a flying/landing event unless there is additional damage that we can’t see. Looks like someone whacked it with something. Maybe there were some kids playing soccer on the ramp and the ball got away from them…

Ammonia did not do this... Agree that it looks like a physical event precipitated the damage. I can’t imagine a natural thermal event would cause this. All of the flights in the last month were well below 10K. I would not rule out vandalism. A hammer fist hit to the center of the windshield might cause this kind of damage.

Perhaps, but I don’t think the plane would be reusable after such trauma. Remember that the wings and nose gear attach directly to the steel substructure. The windows are glued and screwed to the aluminum skin. Any energy transfer sufficient to crack a window would likely cause significant deformation of the skin to which it’s anchored.

Just under $400 from Lasar.

It’s hard to invest in parts sales infrastructure when you don’t have the cash flow to maintain a parts inventory.

You might also check the duct that goes from the NACA duct on the passenger side to the defuser behind the radio stack. There is a little elbow at the inlet that adjusts the valve. It need not be open in cold weather. The caulk you cleaned off was likely a dab of RTV. Perhaps you might reapply in a more “slightly” manner.