RideOrFly

Thanks everyone.

After the recent finding of quite a bit of water in my right fuel tank, I ordered the fancy blue fuel cap o-rings. Before installing, I wanted to confirm that the cap was in fact leaking. So I started with the vinyl tubing connected to the fuel vent and blew. I couldn't tell that any air was moving, which was unexpected considering that I think there's a fuel cap leaking. So I took the fuel cap off and tried again. Still no air moving. Like, none at all. I tried on the left side and the test works as intended, and the air moves with the cap off. I took one of the little twist ties that was holding the hose together and stuck it in each vent. It went all the way in (a few inches) on the right, but on the left only went in about as far as the vent sticks out of the wing. Interestingly, I flew yesterday and was on the right tank for about an hour with no problems at all. This was only in cruise and within glide range of at least one airport, otherwise I used the left. 2 questions: 1. Is it possible that the fuel cap is leaking enough to provide adequate ventilation for the tank? Something has to be or it wouldn't keep running, right? 2. Any recommendations for clearing this? I didn't have anything with me today that I could run in there to try and dislodge anything. I've read through some other threads on blocked fuel vents and I'm starting to think I might not have all 9 of my lives left.

I did something similar in a 172 on my PPL checkride. It was the short field landing, and was the last thing on the ride. Everything else had gone perfectly. I hit the spot, but a little more firmly than optimal. The tires weren't flat, so I guess it wasn't that bad. All the examiner said was "don't do that with your wife on board". I can't be sure, but bet it would have broken something on my plane.

It seems that the Mooney expert is the hardest part to source at this point. The SB looks pretty comprehensive though, not much left to the imagination it appears.

Interesting he says is not a "plane downer" but in this case it could have been. The fluorosilicone rings are the ones I ordered, and they just got here today. Any rough idea what the diameter on the fuel tank vent is?

I just looked back at the logbook entry…seems legit. There were two holes blocked and opened up. The plane was based at HEF before I got it.

I got similar treatment at BNA the one time I went in there. Fortunately it was just a quick turn and it wasn't raining so no harm. But for the cost of that fuel, one really would expect better.

No. It was before I bought it, but wait lists for hangars around here are years and years. I just noticed that you're at HGR--Plane Care was the shop that fixed the drain holes before I bought the plane.

Makes me feel a little better I've never had a drop of water in the left tank so I know I can rely on that one. Hopefully the new o-rings and making sure the drain holes are patent will be enough.

The fact that it looks so old is a little concerning--that tank was just drained and had a new sump installed a week ago. The last reseal was in 2003 if I recall correctly.

One of the only issues during the prebuy was that there were drain holes that were not open. It actually delayed delivery a couple of weeks while the issue was addressed. I assume that the work was completed adequately/in accordance with the SB, but will see if I can get a better look in there once the fuel level is down some. I've never had any trouble getting it completely full.

I've yet to see 160 kts on 10 gal/h but I'll keep trying.

Went out to the airport for a little while this afternoon. I've always given the wings a little shake at the start of the preflight. Today, I shook the crap out of them a couple of times and then bounced the tail up and down a bit. This was the first sample from the right tank. Left tank had no water at all and the gascolater sample was clean as well (taking off on the left tank for the foreseeable future). I took the right fuel cap apart and the inner o-ring does look a bit worn. I recently ordered replacements so will plan to fix that. Any ideas why the water is so dirty?

I appreciate the advice. For sure, the first flight is going to be at least a couple of hours circling the field at 3000 or so. One of our runways has better off field opportunites than the other, so I'll make sure it's a day I can take off on that one.

I don't know specifically how/where he broke the connections. When we spoke yesterday, he told me that the original source of the "rust" appeared to be a bolt in the servo (??) that had corroded. They did not confirm that the debris was rust, just that it appeared to be. Question for anyone--if the fuel flow test was done and the fuel came out clean, that would suggest that there's no debris distal to the boost pump, correct? As far as the tanks go, I was thinking of asking the other shop on the field to drain them for me and put new fuel in. Is that a typical procedure, and I'm assuming a borescope in the tank would likely reveal any debris if it were there? Very sad story about the 150. I'd argue that the fuel contamination brought the plane down, but a steep turn at low airspeed killed them. I try to remind myself that hitting the ground straight ahead at MCA is usually survivable, while a spin is not. But if a guy with those credentials can fall victim to that maneuvering it certainly gives me pause.

Well, I think the shop accidentally fixed my plane. The IA at the shop, who hadn't been involved to this point, went through it yesterday and met with me this morning. He went through the troubleshooting guide and noted a couple of things. First off, the mixture control linkage was incorrectly installed. He would't admit that it was installed incorrectly, rather maintains that it was wrong prior to repair (when it worked perfectly) and was merely reinstalled as it was found. At any rate, he fixed it and the mixture control operates normally now. The fuel flow test demonstrated equal flow for all cylinders. Everything checked good as far as the fuel system was concerned. He rechecked the timing and found that it was good. Everything in the ignition system looked normal. He reminded me that last week (this was after they had signed off on it and returned it to me) when I asked them to check it again, the engine ran rough and afterfired. He reminded me that at that time, the EGT on #1 was 1000-1100 (as it always has been) and that #2 and #3 were down around 600. No mention of #4. Based on this, and in spite of normal compression, he was certain that the exhaust valve on #1 was sticking. I asked if he had done any additional troubleshooting to reinforce that opinion and he said there was nothing additional to do for diagnosis. I asked if he'd done a borescope and he said he did and that the bottom of the valve looked normal. He said he hadn't taken any pictures and that he couldn't. I asked for his recommendation to remedy the issue and he again recommended pulling the cylinder and sending for OH. I asked why we wouldn't just ream it in place and he said that no one would do that because it was just too much liability to assume. I mentioned the Lycoming service instruction 1425 which prescribes and describes the procedure, but he insisted that I wouldn't be able to find anyone who would do that. I was still not satisfied with the valve explanation so I asked that we take the QAA rep up on his offer to help troubleshoot. The IA initially refused and said he didn't need any help and that he knew what the problem was. I'm baffled that anyone would turn down free professional assistance with a problem. We finally did get him on the phone and established to my satisfaction that after the troubleshooting that was done, it was unlikely that the servo was to blame. At that point, I figured it was best to just cut my losses and proceed without the shop's help. We already had a strained relationship and it got pretty heated today, so little chance of savaging that I imagine. I helped put the cowling back on and we moved the plane outside. I got in, and the plane started up perfectly and ran as smoothly as it ever has. I leaned it out and it ran well. I ran it rich and it ran well. I did a normal run-up and it was perfect. I did a full power run up and everything was perfect. I shut down and restarted. No problem. So it did it a few more times, ran it up a few more times and sat there enjoying the smoothness. Of note, I watched the EGTs the whole time--#1 and #4 were between 1000-1100 just as before. But today, #2 and #3 were back up to around 950. It was running so well that I'd have had no issue flying it, except it's 300 ovc and 3/4 SM vis today. I don't know if correcting the mixture control linkage could have fixed this or if perhaps the troubleshooting dislodged some fuel obstruction in the system. I can't for the life of me figure out why they didn't run it after fixing that yesterday to see if it fixed the issue, which it apparently did. I do know that any rational person would have to make a huge leap to think that two unrelated major problems happened at exactly the same time and that fixing one would resolve the symptoms of the other. The story of a stuck valve really doesn't make sense, but I'm even less inclined to believe it when the guy telling the story isn't even aware of the manufacturer's guidance for fixing it. I can't thank you all enough for helping me through this, which I really, really hope is done for good. It cost me a few thousand dollars, but I feel fortunate that it didn't go any further than that. On top of the couple/few thousand more that a cylinder would have cost, I shudder to think what else they would have broken in the process. Ultimately, this whole thing is my fault for not being more involved and informed in the first place. I want to be a pilot, not a mechanic, but I'm learning that I really don't have much choice unless I find someone I can trust.

I’ve heard that from several sources now, including the shop owner—AFTER he had ordered the servo and had my mag overhauled there. *bangs head against wall*

Item #1 on the agenda.

Thank you...I had read about that a while back so I'll take a look in the morning to see if it's installed. If I'm remembering correctly, the AD log said "NA" next to that one, so maybe it didn't have the Dukes pump. The more I think about this whole thing, the more I think that maybe just some water was sitting somewhere in the system that I couldn't sump it which led to the original power loss. That's exactly how it acted when I lost power. It seems like everything since then has been iatrogenic failures.

Absolutely loving that paragraph "the art of troubleshooting." I'm going up tomorrow to spend a few hours and will bring this along. I spoke with the rep from QAA earlier today (they sold the overhauled servo) who offered to help troubleshoot over the phone and even to get the Precision Airmotive folks involved if needed. Very helpful.

I did not know that. It actually occurred to me that I'd be better off putting in a newer engine monitor before doing anything else just to help with diagnostics. Will have to check into the module for the UBG. I agree 100%. There are two shops on the field and I gave up on the other one after they took a similar approach to an electrical problem last year. Unfortunately, I'm kind of stuck with this for now since the plane can't move. Unless competent mechanic would travel--I'd rather pay for expertise than unnecessary repairs.

Much appreciated. I'm going to ask them to do a fuel flow test today and see what the results look like. Also going to ask them to check the mixture control installation--the mechanic assured me yesterday that it was "within limits", but I'm not aware of a specific limit that would apply and I've never flown anything that was that hard to move.

It was replaced with an overhauled unit. I'll have to check and see where it came from. I am going to ask the mechanic to contact them to help troubleshoot, hopefully that will be helpful. I can't see how this isn't the servo at this point. I have a UBG-16, I meant that I don't have one that I can download and analyze. That was my understanding about the valve as well--in addition to not wasting the money pulling the cylinder, I worry about what else will get broken in the process and I'm honestly dumbfounded at the recommendation to pull the cylinder. I really appreciate the time you put into this, and for explaining it simply.

Good thought, and yes, the injectors were cleaned.

Check with @oregon87 about this. I messaged him recently about upgrading my UBG to the CGR-30p and they're offering a very attractive credit to do so.