Shadrach

The holes are located just ahead of the the front tank wall. There are numerous cases of fuel weeping from them including threads started on this forum and in my personal experience. Just providing information. Agreement is not required.

That’s acceptable if you’re leaning to a target fuel flow and are equipped to do so. It does not do much for leaning to a target mixture setting.

Bingo. I’ve been told by multiple Mooney mechanics and pilots over the years that these holes are to allow fuel that has leaked though the front wall of the tank to vent from the wing structure. That’s exactly what it does. Indeed there are scenarios where fuel at the drain hole is the only external evidence of a leak.

Like I said, semantics. The BMP as it was taught to me nearly 20 years ago by one of APS’s instructors was as follows: 1) Pull (not twist) mixture control briskly to deceleration. 2) Enrich mixture to establish peak EGT from the lean side. 3) Lean to the desired mixture setting from peak. Apparently it means whatever people want it to mean as long as it occurs on the lean side. To be clear, I don’t think the BMP is needed for an NA engine. I do lean that way, but do so because it’s faster, not because of the dreaded red box.

Nice informative first post by an account created on Friday, specifically to reply to this thread.

Just to close out this side bar. I’ve confirmed (I think) that LB and GB are three hole flutes… the Colorado accident 231 is an LB and has the 3 hole flute.

It’s semantics at this point. One man’s BMP is another's eternity in the red box. The document makes no mention of pulling as in depressing the button on the vernier and pulling the knob until deceleration. The genesis of this procedure was APS perhaps 25ish years ago. No one in 1982 would have interpreted that document in that way. It simply says lean past peak RPM to desired RPM. Do not operate the engine above 75% while leaning for more than 15 seconds. The instructions are pretty straightforward and easy to achieve without a BMP.

No matter what model you’re flying, you should have an accurate trim indicator

I don’t know for sure, but given that compartment and station had been deemed useable for the initial STC, I would not be surprised if it’s the same for all.

@rturbett Does the aircraft begin to "wheel borrow" if you don't pull up?

My first input after take off is always to trim nose down a swipe. My second trim input is to trim nose down after raising the flaps. I am not buying the worn donut theory. Something is not rigged properly and my first guess is the indicator.

For what it's worth, I have never found water or evidence of water inside my wings. If water was pooling inside, I would expect to see evidence of some sort. Even using a light duty pressure sprayer (600PSI) the outside did not cause my wings to leak. I know this because the last time I did tank repairs I hosed out the wing tanks as well as the surface of the wings. In less than hour I was into the outboard wing reconnecting the outer sending unit. No water to be seen anywhere inside wing. It's conceivable that it is entering through the bottom wing skins during flight, but again no evidence. I have flown in rain so heavy that the noise was competing with the engine/prop. I have had small amounts of water find its way past the firewall and even into the ventilation system, yet I have never seen evidence of water inside the wing. Not saying it does not happen. Just saying I have never seen visible evidence. My apologies for suggesting something so obvious as verifying all aspects of the installation STC. Given you are the only person that has ever raised this issue, I thought it might be tied to your particular installation. Good luck. I hope you figure it out.

Do you have the Monroy Aerospace upgrade below? Have you contacted them for advice? I believe there have been several different shops acting as installers of this STC since it was approved in the 80s. Not hard to imagine that there might be inconsistencies in those installations. First thing I would do is verify that the installation complies precisely with the STC. It seems to me that drainage would have been a consideration during approval.

5 pages of: …” don’t run high power LOP because it’s dangerous” …” Lycoming/Continental say you can’t hurt your engine below 75/65% so don’t lean above that depending on the make of your engine. …”You can do it but not unless you really pay attention” And then on page six: …”Leaning to 100ROP at >90% power at cruise climb airspeeds is just fine”.

One of the unique things about the TIO-540-AF1B compared to other turbocharged engines is its more thermally efficient 8:1 compression ratio which should yield lower raw TITs, making more mixture options available to the pilot.

I read the doc and I am not seeing the BMP. It says to lean at full throttle from full rich through peak RPM until the desired RPM is reached. It also says to avoid remaining at or above 75% for more than 15 secs (that’s an eternity to get past peak) at any setting other than full rich. As I read it, this process does not guarantee that the engine is lean of peak EGT; it guarantees that the engine is lean of peak power. I have always found the power charts for different NA engines curious. This POH says the engine won’t make 75% power above 6500’. My POH say that my engine will make 77% power at 10,000’ on a warmer than standard day temperature.

Yeah, let’s hope not.

That article is a good read. That being said, leaning to 100ROP at 3000’ in the climb is too aggressive in my opinion. That’s well above 90% power.

My old machinist calipers aren’t the best but these are the numbers I came up with. spring length is .575 spring width is .220 ball diameter is .219

That should not be possible. It reads like someone installed the wrong spring or perhaps the wrong ball. Spring should engage the ball before it engages the threads. I made the below video several years ago to illustrate just what I’ve said above. You can see that the Springs as engage the ball before the retraction screw is threaded.

The spring was damaged? How?

I have a pump on the shelf, but I cannot break it into parts. I am sure you can source a spring of similar size and spring rate. The HE1518 is not so critical in terms of precise spring rate because that valve is manually operated by a cam and needle. The spring simply holds the valve (ball) against the seat. Err on the side of more compression than less. If you had lost an HE1516 you would need to be much more precise in sourcing the correct rate spring as it must be heavy enough to hold the ball against the seat but light enough to be unseated by atmospheric pressure when a vacuum is created on one side. I can provide spring dimensions and pictures if that helps.

Same here, with some Chief, Champ and an hour or two of Stearman time thrown in for good measure,

Nice looking bird Hector and well equipped. What’s the UL?