jclemens

To take this to an overhaul would bump the price up substantially. If it was only 5K it would be a no brainer. As it is right now, the repair won't be much more than that, whereas an overhaul would be in the mid 20's. I usually agree that overhaul is a good idea, but in this case the engine is only 8 years old. At the rate it is flown he will be at overhaul in 2-4 years anyways. All the cylinders actually look great. We have the valves out and none of them have and unusual deposits or show any sign of leaking. The jugs will get cleaned up today and checked dimensionally. from what I saw yesterday they will probably get the seats touched up and the valves lapped back in and reassembled with new rings. A worn guide can cause a sticky valve that can contribute to this type of failure, but sometimes they just fail anyways. We have never had to split a open a roller engine anytime other than major overhaul. Yes, it's true the rollers must be tossed and new ones installed, they are a few thousand more to overhaul because of this. Lack of use certainly contributes to the problem. Most cam failures I have seen were on engines that were put back into service after a period of inactivity. ECI has PMA approval for all their parts, I think they manufacture them.

All the new ones have roller cams now. We build lots of IO-260-L2A's with roller cams, I have never seen one with a cam problem. I have seen lots of old engines with this same issue. Unfortunately the cases are different, so converting to a roller cam at overhaul is not an option. Unless of course you send the old one back to Lycoming in trade for one of theirs.

As stated before, there is no oil analysis. I don't know what good it would do now. It's pretty obvious that there was metal in the engine. This engine is going to get the what would pass for an overhaul if it wasn't aviation. It will be a "Repair" only because we don't plan on doing the fuel or ignition systems.. All the internals will be dimensionally inspected and dealt with accordingly. We won't be doing NDT, a little metal contamination doesn't warrant the crank to be magnafluxed. It will go on the crank polisher and get cleaned up. It will be reassembled with all new bearings, new cam followers, new cam, new set of pistons and rings, and new a gasket set.

You're right, it doesn't disappear. The piston skirts are imbedded with metal, also the bearings have a little bit imbedded in them as well. Both will get replaced. This has probably been like this for a long time, many oil changes ago.

Here are some photos I took today. The cam follower is an ECI part and you can see the date 12/08 on it. All the rest are the same date, they are all fine. They will all get replaced with new along with the cam during this repair anyways. The cam is also an ECI part, it was probably purchased together as a kit with the cam followers. There was no metal at all in the filter, also none found in the screen. The crank and rods are all in great shape, no damage done there. Cylinders look good too.

Call a prop shop. We are a repair station, so is the prop shop I use. This governor was just overhauled last month. They will tear it down, clean it, stick it on the test bench and set up the pressures again. I'd be surprised if they even charge me for more than a gasket. I just bought an overhauled governor outright with no core for $2600 for another aircraft. Sounds like you have had some bad experiences, I suggest you find better people to deal with. Unfortunately, there are some unscrupulous prop shops out there, other vendors as well. There are also some very good ones. I think the key is to find a respected high volume shop, such as mine, that has a good rapport with their vendors and let them handle it for you. When owners start price shopping repairs at specialty shops themselves, it usually ends poorly because they typically pick the cheapest quote. That usually doesn't end up being the best option. The pros know who we can send stuff to that will return a quality product at a predictable price. I have done business with every prop shop in this state and many others, I now only use one. If I need something that's outside of their capabilities I let them send it to their preferred vendor. Theres a very high probability that the governor on this plane wasn't even subjected to metal contamination. It was put on with clean oil and nothing in the filter or screen was found. If the filter and the screen are clean now (yet to be determined), this cam damage could have been there for a while. It could have been the cause of the prop governor needing to be overhauled before though. Several pre-existing indication errors and power problems lead to the OP flying at lower power settings than he though he was at, cruising at 2000 RPM and 20 MAP. Those have been corrected and now he's flying at normal power settings that are higher than before. The cam lobe problem has probably been there for a while, but just didn't present itself as noticeably due to the way the engine was being operated.

You can pull the valve covers and use a dial indicator. I think the lift is .350 or something similar on all the lobes. You don't really need to know the exact number, just compare them all, usually only one lobe goes, so that one will be a lot less than the others. I find it to be just as easy and more definitive to pull two cylinders so I can look at everything. No oil analysis on this engine. An engine monitor would have absolutely shown this. EGT would have been low on the #2 cylinder during engine roughness (real low). In cruise when the engine wasn't noticeably rough, The EGT would fluctuate, on a datalog graph it would show as a "jagged" line rather than a basically smooth one. CHT would most likely be high due to improper exhaust scavenging. You don't really need to know any of that, just know what your engine monitor is supposed to look like when everything is good, and if it ever looks any different, have it checked out.

Actually yes, they are taken through the hole where the #3 cylinder belongs. Of course I pulled the #1 cylinder off first, you can't see the damaged lobe from there. (Well with a borescope you can, but not easily)

Yeah, you can see the cam follower face in the photo, it looks like the surface of the moon. There is still a cylinder on that side, so the valve spring is hold it against the cam. I'll take some better photos when I get it all apart on Monday (maybe Tuesday). The governor will be fine, just needs to be flushed properly like everything else.

Haven't actually looked in the filter yet, it was clean a month ago. There is some metal imbedded in the piston skirts. I'll split the case Monday and take some more pictures. They will get replaced during reassembly anyways though. With a little over 850 hours on this run, the plan is to tear it down, clean it up, replace the cam and lifters with new, and reassemble with new bearings and gaskets. Obviously if we find anything in the tear down that needs to be addressed we will fix that too. Should be done in time for OshKosh.

Well, we found the problem. Cam lobe gone on the #2 exhaust valve :/ First pic is the bad lobe, second is a good lobe for comparison.

An engine monitor is definitely helpful, no doubt. I could most likely figure this out from a JPI download, certainly narrow it down to one cylinder. I have communicated the benefits of an engine monitor, maybe in the future he will install one.

I spoke with the OP today regarding the issue he is having. I figured I would post here to shed a little light on things. My shop did the annual on his aircraft. During that annual a LOT of issues were dealt with that he inherited when he bought the plane. Prior to annual, the plane was not developing full MAP due to a collapsed intake coupler and a leaking induction tube. Nor was it being operated at the proper RPM due to a grossly inaccurate tach and a defective prop governor. Along with correcting these issues, the front cowling was modified with the LASAR closure. This plane is not equipped with an engine monitor, so it's a little more difficult to troubleshoot. I think the oil pressure difference he is used to seeing vs. what it is now is caused by the fact that the engine now makes rated power and is being operated harder. The pressure is well within limits, I don't see any correlation with that and any engine roughness. I suspect an exhaust valve sticking at low power after cruise. He is bring the plane to me tomorrow for us to look at. We looked at the plane for the same issue about a week or so ago briefly. Compressions are all fine, plugs and injectors rechecked as well as timing. All good there. This time he is leaving the plane so we have more time to investigate. I will post back once we determine the issue.

No, because they do not manufacture products that have to meet any standards, aka TSO/PMA. That's why they are experimental. A piece of paper from the EAA is not going to change that. The responsibility falls on you, not Dynon or the EAA. That's why they are priced accordingly. An aircraft loaded with cheap experimental avionics, no matter how flashy, is definitely going to be valued less than one thats loaded with certified avionics.

We should start a class action lawsuit against Bendix King, I know they could upgrade a KX170B to WAAS if they wanted too! The lifespan of avionics equipment is exponentially greater than any other piece of electronics. I don't get why people get all up in arms when they are told their 20 year old GPS is no longer viable. Do the same people get pissed off when they can't play a Blu-ray disk in their betamax player? Do they drive a 20 year old car and expect it to perform like a brand new one? How about a 20 year old computer, do you expect that to be upgradable to compete with a brand new one? I ,for one, like new things. I have customers that tell me all the time that a new GTN 750 won't do anything that the KLN89B they have in the panel does...really?

Almost all of the rules/restrictions suggested so far in this thread are already in place. But, you know what they say about rules. Recreational RC pilot's are to remain under 400 feet AGL. The pilot is to now be registered, and the registration number permanently affixed to the aircraft. Operation within 5 miles of an airport is usually prohibited. But, there are a LOT of sanctioned RC flying fields much closer to airports than 5 miles. Some are even at airports. The FAA and ATC people are taking RC incidents very seriously. If you fly RC, like a lot of the aviation community, be sure you take it just as seriously. If you are a licensed pilot, any violations made with RC aircraft will be taken against your certificate. Hitting one in flight would most likely be no worse than hitting a bird. They are mostly plastic and for the most part light weight. There are large 55lb drones out there, but the pilots of those will be more educated, having invested a significant amount of time and money into his/her craft. You will probably encounter some idiot who went out and bought himself a ready to fly quadcopter and a case of beer, who needs to be arrested and paraded around on the news to deter others.

Sold!

Yeah, this. There has to be more to this story.

Thank you, a lot of time (money) was spent making everything run so evenly. No, Cylinder #1 is the right rear. The factory CHT probe resides in the location of the other 5 JPI probes on the #1 cylinder. It has a piggy back style probe underneath the factory one. It's not accurate. I have removed the factory probe and made test flights with all 6 identical JPI probes and the #1 cylinder is the same as the rest. I contemplated leaving it that way, but the inoperative factory CHT annoyed me. The factory gauge is not accurate either. The inaccurate reading on the JPI annoys me too, but, too a lesser degree.

It stands to reason that if an engine needs to be dehydrated for storage that it must require proper rehydration before being put back in service. Seeing that there doesn't seem to be a product on the market for this, I will start designing one immediately. I don't want anyone flying around in a dehydrated engine. If you guys requiring this device could just send me $200, that way I know how many to build.....

Some of them even use it that are not allowed to. There are tales of tubular structures being sealed up and used to store hidden giggle gas in the T6 class.

The Trig TT31 is a slide in replacement for the old King KT76A. A simple wiring addition from your WAAS GPS will give you ADS-B out too.

14 weeks in a hangar is not a long time. I would just park it. Unhooking the battery wouldn't hurt, in case there is something on the hot buss.

The Reno Air Race guys have been doing that for years. It works, but it's dangerous. Just like in cars.

The Merlyn should be required equipment on any aircraft with the TSIO-360. It reduces wear and tear, increases critical altitude, and makes controlling power easier.