cujet

Maybe I missed something, but why not simply replace cam, lifters and rings? Then go on your way for the next 1000 hours or so. I chose a Firewall Forward "drilled camshaft" for my engine. So far, the lobes look great (via borescope up through the oil drain) and no significant iron in the UOA's.

I'd simply replace the failed wire with a like kind new one. (if you can find one, or have one fabricated) Wires last a very long time, so it's quite likely your other wires are just fine. The problem is that it's now hard to find the components to make spark plug wires. What used to cost $20 in parts now requires an entire harness replacement at $400.

Oh, gotcha. I was thinking about the evils of case law. Completely off track... It's a good idea to keep quiet around any government official. In my various dealings with them, I keep nearly 100% quiet.

Oh, it's worth it. Exercise your freedoms while you can. I can't predict what the future will bring, but we certainly have "creeping authoritarianism" and if things continue on this path... I am old enough to remember carrying my 22 rifle (unloaded) down the hall in my High School, to the "rifle club" range out back.

The use of a drug sniffing dog is not an "end run" around the Constitution. Period.

Too bad you are not here in South Florida. I'd be happy to help you resolve some of these issues. From what I've read, you really needed to address these issues prior to FAA intervention. I deal with the FAA regularly (as an aviation professional) My experience has been all over the map. From a recent, stunningly complete audit which went very well, to an FAA ambush that was intended on causing hardship (which I also passed by sheer dumb luck and a bit of a nagging feeling at the start of the day) . The one thing that I truly dislike is the "ramp check". I try my very best to avoid these at all costs. A violation here could cost me my job. My goal is perfection in my Corporate flight department. It's clear the instant you walk in my office, and when you view my aircraft. It's clear to the FAA also. I like things perfect!

Interestingly, the FAR's permit pilots the authority of interior removal, installation and rework. Carpets hold dirt and dust. This is a good thing, as shoes are often dirty. We fly an Extra 300L, without any form of carpet. The amount of flying debris in this aircraft and the airborne dust always amaze me. Of course, you are upside down when you notice it.... Believe it or not, NASA noticed the very same thing with the lunar lander. No matter how clean they worked, it was always dirty. Carpets really do help prevent loose dirt.

Ed, I'd be glad to do so. I'll try to do this myself. And, you have asked me for this before. However, the folks I have working for me don't seem to understand what I want, and go forward with plug cleaning. I've started using TCP for other reasons and this has resulted in fewer fouling incidents. Yes, the soft balls seem to be universal to my operation and every piston aircraft gets Camguard. It does not seem to cause any trouble. Some time ago, I thought I had a fouled plug and pulled said plug, found the balls. However, it was actually an intermittently sticky exhaust valve causing the misfire.

Just an FYI, Here in South Florida, cylinder rust is a constant problem. As soon as our flight department started using Camguard, cylinder rust stopped. It's that simple. Conversely, I've been noticing small, circular, soft deposit "balls" at the base of my sparkplugs, in all the aircraft I use Camguard in. I spoke to Ed about this and I'm not satisfied that it's something other than Camguard causing this. Note: all of my aircraft, aerobatic or otherwise, consume oil. Plenty of oil finds it's way on to the plugs. It's the nature of our operation.

In the corporate jet world, we regularly paint sections of aircraft with new "Jet Glo" or "Acry Glo" paint without any matching concerns. It simply works well. However, we often buff, using "Flitz" metal polish afterwards to blend the two paints together. I'm not a fan of the Preval sprayers. Yes, they work, but the Preval won't provide precise control or superb atomization. A $10 Harbor Freight airbrush with small compressor, such as the construction style $39 pancake compressors, will work infinitely better. (I generally avoid airbrush compressors) Yes, bare aluminum should always be treated with etch and alodine, use care, and a bit of scotchbrite, very gently. A couple of thoughts: 1) Feather the edges of the old paint carefully with a block and fine sandpaper. Careful prep results in a nice job. 2) If you can compound the repair with Flitz afterwards, wet sand just outside the repair area with 2000 grit sandpaper. Promotes adhesion and matches color, by removing the discolored surface. 3) After spraying, clean the airbrush, fill with slow reducer and carefully overspray the area, especially the edges. This "flows" the dry overspray around the edges. Done properly, no buffing is required and a very smooth repair will result. 4) Consider buffing the entire area with Flitz after the paint has cured. It simply works.

The upcoming ADSB requirements will track your specific movements anytime you fly, VFR or not. They are specifically tied to your aircraft, your exact position, speed and predicted course (our WAAS GPS accuracy is hovering around 7 feet! ) AND "PM" ADSB requirements are coming (hacker free, can't be turned off, "protected mode" ) . There was an FAA comment period on this. The FAA openly asked a question about privacy concerns. ADSB is a powerful system, and, unfortunately, it's necessary for next gen navigational requirements. I'd argue the positive separation benefit of ADSB is worth the privacy cost. Knowing that altitude and positional errors "may" be mandatory, computer generated violations in the future. (we are trending that way now) (consider blocking an altitude range when under positive control)

I am not a big fan of the Stec 30 and it's very limited functionality. While it clearly has some advantages, it's not an inexpensive solution when viewed objectively, and it's not inexpensive to repair. The control knob's internal Ujoint setup is a plastic $1 part, prone to failure and will cost you an absurd $1,100 to $1,500 when it fails. Stec autopilots cannot be repaired by your local avionics shop and the turn time is often not good. I currently have one sitting on the shelf with 2 issues. The Ujoint is broken and the optical pickup for the mechanical gyro (an integrated LED emitter and sensor, $9 at digikey) is bad. Stec/Cobham wants $900 for an evaluation fee, $1,100 to repair the Ujoint and nearly $3,000 to replace the circuit board with the bad sensor. At that cost, might as well purchase a replacement. Better yet, do what I did and get something else. Given the choice, I'd go for a modern digital setup.

I'd also like to forward this to my state representatives. Please consider giving us permission to use your experience and your words.

I've seen that picture before. However, each person is standing directly on the spar, and the load is evenly distributed. Consider what happens when 80 pounds of dog paw is concentrated in 3 square inches of unsupported sheet aluminum. (which by the way is far beyond the 1G load of 17 pounds per square foot) . Or put another way, the structural limit of 2.5x the 1G load. The aluminum can be slightly stretched and that section of the skin is no longer in tension when subjected to loads. Thereby placing higher loads on the surrounding structure. Also, consider what happens when the dog walks on a fabric wing. We really need to educate CBP about airframe structural limitations.

Ouch, I resemble that remark... However, I am an aircraft owner... Maybe that's why that pretty little girl likes to hang out with me... I thought she really liked me...

I'm sorry you had to deal with belligerent government agents. I get the privilege of dealing with CBP agents regularly, they suck. In my dealings with them, I refuse to be interrogated right from the start. Name, rank, serial number (in essence) , nothing else. I don't let the attitude affect me, and trust me, it is not easy keeping a smile on my face. They have this down to a science. If it drags on, I demand the presence of my lawyer. There are very few things I will ever say to them. Internet advice is, in reality, worthless. Everybody has an opinion and some of the higher bandwidth individuals have valid thoughts on the matter. I will suggest this: Nothing you do is going to affect the outcome. I suggest silence for reasons of self protection. I'd love to share a large number of stories with you, but in the interest of keeping it brief.... We (flight crew on a corporate aircraft) had a CBP agent actually threaten us with deadly force, quite angrily I may add. The crime? Supposed video and audio recording of CBP agents at work. Note: From a human nature standpoint, it was an interesting spiral of events in the agents head, as he worked through the possible charges he could bring to bear against us. In any case, he settled with a sure bet, "wiretap and video" charges, and then the gun came out. As I am sure he believed we had iPhones in our pockets and could somehow justify his awful behavior. Being the prepared individual that I am, I advised the other crewmember that we leave our phones in the aircraft, so we did. (remember, they occasionally confiscate electronics and download the information contained) (often erasing information in the process) We got lucky that time, as the only things on our persons were passports and empty wallets. Was there any sort of reason for the belligerent behavior? No, we did nothing to cause problems, other than we crossed paths with a tyrant. The same distorted individual we come across every week. You can't imagine the infuriating situation when the CBP agents removed the engine cowls from our Lear with thrust reversers. (the top cowl is also the TR, with it's associated electrical and hydraulic connections) Another thought, what's the published maximum load per unit area on the upper wing skin? The dog may have exceeded that load rating, necessitating an upper wing skin replacement. I'm guessing the dog walked in the "no step" area. From a technical standpoint, stepping there is absolutely prohibited. Think I'm being absurd? Think again. Many aircraft cannot handle concentrated loads on the upper wing skins. If you would like to know the reasons why, PM me.

I'm willing to work towards that end. Let's put pressure on the FAA to change...... I'm 100% sure they are willing to listen to the experts actually doing the work.... In all seriousness, I'm not at all certain the federal government has the Constitutional authority to disallow, what are, in essence, minor alterations. The FAA used to allow field approvals for just this reason (at least part of the reason was an alteration pathway for owners/operators, seen as needed under the guide of the US Constitution as blanket prohibition would be seen as federalism) . Field approvals are a thing of the past, because the FAA cannot be bothered with them anymore. But from a legal standpoint, the private, part 91 owner/operator of a light aircraft is not engaging in air commerce and therefore cannot be regulated under the commerce act. Nor can it be said that the greater public good is at risk (remember the 12,500 pound or more limit) by altering and testing a light aircraft in a safely defined manner.

I neglected to mention that moving the valve around inside the cylinder is actually quite easy. From the bottom spark plug hole, use a forked rod to push up the valve. From the valve guide, use a strong, rare earth magnet tool. From the top, a flashlight or 2 prong mechanical fingers (the larger kind) It's really a non issue.

I'm a Director of Maintenance in a high end corporate flight department. However, I do get to play with little aircraft also. The above advice is generally very good. Run it hard, check again. Consider repairing your cylinders. Yellow tagged "overhauled" cylinders are very likely to be re-welded units from "who knows what or where" (yes it matters) and they often have a bad reputation for good reason. I'd avoid them, given the choice. Here is what we know. You have 2 very specific issues, and don't seem to have any others. It's very likely that repairing each specific issue will be easy. The above suggestion for "lapping them in place" is a good one if conditions warrant (I strongly suspect they do) . You may not find published procedures from the manufacturer on how to do this in situ. However, you could follow lapping procedures properly, without ever removing the cylinder. I'm taking a WILD guess here at internal conditions, but here goes: Note: You may want to operate the engine with some TCP to help remove lead deposits prior to maintenance. It does help, slightly... 1) Pull the plugs on the affected cylinders. 2) The one with the leaky ex valve, pull the exhaust pipe, likewise, the intake pipe for the other cylinder. 3) Remove the affected valve springs, consider replacing these 2 valve springs with new, as new will result in higher seat pressure and better heat transfer/sealing (they are very cheap) . 4) Pull the valve stem up the top spark plug hole and clean off the carbon by careful scraping and using maroon scotch brite. I do this using shop air flowing into the lower plug hole to prevent debris problems. THEN CAREFULLY INSPECT THE VALVE. Proceed if it looks OK. 5) Run a properly sized valve guide reamer CAREFULLY through the guide, loaded with grease. This will remove carbon and allow the valve to center properly on the seat. DO NOT REMOVE METAL from the guide. (unless it's just a burr) 6) Use care to apply coarse valve grinding compound on the valve seat. Then lap the valve, using standard practices. Consider fine compound as a second round. I like using a battery drill, and rubber hose on the valve stem. Using both directions and regular valve lifting off the seat to allow the compound to flow a bit. This takes work. Don't be afraid of grinding too much. It's not very likely unless you spend 40 hours grinding. 7) Clean off the compound like crazy, being sure not to allow grinding compound into the bore. Wipe off the valve seat and face. 8) Reassemble and test for leaks. In fact, I might just run it hard and test afterwards. I'll bet you a dollar this fixes the problem and prevents future compression deterioration from these specific issues.

I don't put too much faith in "overtorqued spark plugs" causing cracking. Here is why: Aluminum has a distinct fatigue limit. Quite simply, aluminum accumulates cycle fatigue. Either through many, many small cycles or far fewer large cycles. It matters not whether it's a wing spar through turbulence, or a cylinder head subject to combustion events. Aluminum has predictable behavior. Add in the heat of combustion and the violent nature of combustion, and the fatigue limit is reached earlier than in the wing spar example. Lets look at what we can control. We can operate the engine at somewhat different RPM's, thereby changing the number of cycles. We can control the BMEP (cylinder pressure) of the engine via throttle and mixture (and engine design) and we can control operating temperature through power settings, operating conditions and cowl flaps. Other variables such as baffling airflow and climb angle, climb speed and so on come into play. All of these (and more) variables will affect the "cycle count". I hate to say "just accept it", but there is no question that such cracking is normal in aircraft engines. This issue has never been fully resolved. As you might have guessed, new cylinders (not overhauled) will result in much lower risk of cracking. As will proper operation and cooling. It would be interesting to see a graph of the lifespan of specific cylinders. I'd guess Lycoming angle valve cylinders fail prior to the 2nd overhaul with high frequency. My cylinders had 1700 hours total time on them when I overhauled them. We very carefully checked for cracks and there were none. However, I don't hold the belief that I will get another 2000 hours out of them. Time will tell. Interestingly, we now test aerospace aluminum alloys with piezo drivers that cycle the aluminum at extremely high frequencies. This accelerates fatigue testing and has proven to be a worthwhile tool. Most aluminum fails in predictable ways. However, I wanted to add that Lycoming cylinder heads are also subject to other stresses. The valve guides and seats are pressed in. They expand and contract at slightly different rates than the aluminum does. But the big one is the stress created by screwing the barrel into the head. It's an interference fit and produces a perfect seal. Imagine the stresses located around this area. Shock cooling: I'm not a big believer. 4 billion flight school airplanes doing stall practice and other ham fisted operational practices have fewer cracked cylinder heads. This does not mean one should shock cool an engine, and expect longer life. But it is a data point against the theory of shock cooling resulting in instant, massive damage. I do know this: data download study shows that throttling up for takeoff results in far greater temperature change rate than does pulling an engine back slowly to idle at cruise alt.

Ohhhhhhhhhhhh yeah!!!!!!!!!!!!!!!!! Great pic. A pic like that speaks volumes. Classic airplane, flying "freely" over the coast. Freedom itself!

If you read the CAFE testing, they discovered that the elec ign worked it's magic at the lean limit. Allowing better speed and efficiency during LOP operations. I simply don't fly that way.

I tried on both my browsers and I had no problem. Try a google search for CAFE Foundation Ignition dynamics.

Data comes from real world users in the experimental aircraft world, myself included. Mostly on Lycoming engines, but certainly not limited to them. There are many Continental users of electronic ignition systems. One thing that is nearly universal, electronic ignitions result in smoother operation. The ignition advance really helps ground ops, low power ops, and during descent. But rather than take my word for it, check out CAFE Foundations testing. Here is some light reading... http://cafefoundation.org/v2/research_reports.php (the source for the info) http://cafefoundation.org/v2/pdf_cafe_reports/ignition1.pdf http://cafefoundation.org/v2/pdf_cafe_reports/ignition2.pdf http://cafefoundation.org/v2/pdf_cafe_reports/ignition3.pdf You will note that the electronic ign actually resulted in a slight loss of top speed, under full power operations. I've written on this before. Electronic ign may not help an underpowered aircraft much. Some aircraft are operated at full throttle, maximum possible power, all the time. My 200HP Lycoming is one of those engines that never see LOP operations, or high altitude. An Electronic ign is not going to help me much, as fuel flow is always at max power.