---------------------------------------------------------- TeamGrumman-List Digest Archive --- Total Messages Posted Tue 11/09/10: 9 ---------------------------------------------------------- Today's Message Index: ---------------------- 0. 12:21 AM - Coming Soon - The List of Contributors - Please Make A Contribution Today! (Matt Dralle) 1. 10:36 AM - Re: Cylinder woes (Gary Vogt) 2. 10:45 AM - Fw: THE FOCKE-WULF Fw 190 FLIES AGAIN (Gary Vogt) 3. 04:06 PM - Re: Cylinder woes (FLYaDIVE) 4. 04:14 PM - Re: Cylinder woes (FLYaDIVE) 5. 06:47 PM - Re: Cylinder woes (Gary Vogt) 6. 06:49 PM - Re: Cylinder woes (Gary Vogt) 7. 06:55 PM - Re: Cylinder woes (Gary Vogt) 8. 11:03 PM - brakes (Gary Vogt) ________________________________ Message 0 _____________________________________ Time: 12:21:40 AM PST US From: Matt Dralle Subject: TeamGrumman-List: Coming Soon - The List of Contributors - Please Make A Contribution Today! Each year at the end of the List Fund Raiser, I post a message acknowledging everyone that so generously made a Contribution to support the Lists. Its my way of publicly thanking everyone that took a minute to show their appreciation for the Lists. Please take a moment and assure that your name is on that List of Contributors (LOC)! As a number of members have pointed out over the years, the List seems at least as valuable a building / entertainment tool as your typical magazine subscription! Assure that your name is on this year's LOC! Show others that you appreciate the Lists. Making a Contribution to support the Lists is fast and easy using your Credit card or Paypal on the Secure Web Site: http://www.matronics.com/contribution or by dropping a personal check in the mail to: Matt Dralle / Matronics 581 Jeannie Way Livermore CA 94550 I would like to thank everyone that has so generously made a Contribution thus far in this year's List Fund Raiser! Remember that its YOUR support that keeps these Lists going and improving! Don't forget to include a little comment about how the Lists have helped you! Best regards, Matt Dralle Matronics Email List Administrator ________________________________ Message 1 _____________________________________ Time: 10:36:37 AM PST US From: Gary Vogt Subject: Re: TeamGrumman-List: Cylinder woes Well, Barry, What are we talking about here? Gears? or Cylinders? As for the gears, how many out right failures where there? Not many. For the most part, the bottom end of any Lycoming engine will run seemingly forever with a bad cam, bent rods, and a crank that needs to be turned. IF the engine has been taken care of regarding oil changes and regular use, the bottom end is good for 4000 hours. Rockers: Here, I'd have to agree 100%. Two nearly identical rockers with no stamping showing how they go in. In 1984, I was doing a very thorough annual on my first Cheetah. The engine had 600 hours on it since new. The rocker cover gaskets were leaking, so, I decided to change them. In the process, with a brand new Lycoming overhaul manual in hand, I decided to do a dry tappet clearance check, just for shits-n-grins. Inside the maintenance hangar, about 20 yards from the main FBO, I started carefully removing all the parts. On the work bench, I laid out everything in the order I removed them. During the cleaning process, I noticed a there was a difference between the rockers. Strange this was, from the factory, one side of the engine was one way, the other side was different. I asked the mechanic there, Jack, a guy who had been working on planes for some 30 years, which was which. He said, and I quote, "I don't know. I've never noticed a difference before." I called Lycoming and talked to an engineer. He didn't know either. Several transfers later, I got an answer. Do you know the logic behind the different rockers? The squirter is supposed to squirt oil on the valve stem . . . exhaust only to help cool the valve. The other one is supposed to dribble oil onto the rocker . . . . intake only. These engines have no oil seal on the valve stems. Squirting oil on the intake only makes oil go into the intake port, coat the inside with residue, and burn more oil. Waiting for more oil to be delivered to the heads: This is a major misconception. Born, in part, by Bill Scott and Bill Marvel. Sodium filled valves were first used almost 100 years ago. By the mid 30's there was a lot of research being done on sodium filled valves. Why? Because, at the time, rockers were out in the open. Sodium filled valves offered a way to shed heat without much oil. In fact, research done by Samuel Heron in the late teens, early 20s, showed that excess oil on the valve causes valve sticking. And, if you think that sticking valves are unique to Lycomings, you haven't kept up on the valve problems (using solid valves and lots of oil) in Continental engines. Do a little research regarding oil on sodium filled valves. The problem is really due to the geometry of the rocker/valve stem during operation. The side loads on the valve cause the guide to be worn excessively*. This is true of ALL engines without roller rockers. In this respect, the solid lifter engines (i.e., O235) are better. Ideally, you want to get roller rockers to get rid of the side loads. Hot Rod magazine had an excellent article on valve geometry not long ago. * this is THE reason why I recommend a top overhaul with new cylinders at 1000 hrs. I've pulled a lot of cylinders with 1000 to 1500 hours on them. I send them to Ken for tear down and inspection. I pay for the research on this one. In every case, the cylinders have cracks in the exhaust port. Most, but not all, show excess wear in the guides. The ones that don't show no correlation between them. (that is, without getting Charlie Epps to do a math analysis of it.) It just isn't worth patching the cylinder to get another 1000 hours out of it. It'll never make it. Fins on Superior engines: Now, I ask, was that a work of art or what? Really pretty weren't they. Problem was, those machined heads (in place of cast heads) gave up 30% of the surface area needed to shed heat. Casting flashings: I ground out the flashings on about a half dozen engines. All with JPI engine analyzers. No change. Sloppy workmanship, for sure, but not critical. The new heads are a whole lot better. ======== I feel you can learn many things from stories. I also enjoy your stories. --- Thanks My first thought was WHO did the overhaul? --- It was done by an FBO in New Jersey My second thought was: She is fixating on the numbers and not the situation. Everyone would like a quick - cheep cure to low compression. --- She is a lawyer. What can I say?And I have to ask... Sorry Gary... Why did the block crack? --- My guess is the crack was there from the beginning (well, before I got it). Ken told me this is usually due to the alternator bracket on the bottom of the engine breaking and the alternator hanging on the upper brace. The boss the upper brace is attached to, breaks.I'm twisting the knife here and it is NOT fair. A cracked block is far from normal and not something that can be blamed on Lycoming. And if the crank was scored there must have been quite a bit of heat. Maybe before she purchased the plane and as you said: " I just couldn't convince her that the engine did not really get a real overhaul." And I agree, you do get what you pay for. But you should not have to pay too much. When it comes to repairing a problem, I say it a little differently: "Pay me now, or pay me later; the problem is not going to go away." --- She paid way too much for the plane. It was full of corrosion. Under the instrument panel was a nightmare. Someone had wired in an audio panel, one wire at a time. There were wires everywhere. --- Side note: same plane. During the first annual, I noticed a dent in the bottom of the right wing. It looked like the wheel pant had dented the wing. Now, to my way of thinking, this is impossible. Upon further investigation, the four 3/8 inch bolts holding the axle onto the fiberglass gear leg were bent. The gear leg was splintered. --- Continued: Before she came to me, she bought a LoPresti nose bowl because the engine 'ran' hot. The JPI shows it anyway. After installation of the LoPresti nose bowl, it ran even hotter. This was my first LoPresti nose bowl. Turns out, you can't tuck the baffles into the top of the nose bowl inlet and form a tight seal. You really need to know what you're doing to properly seal the LoPresti nose bowl. 99% of the 75,000 mechanics out there haven't a fucking clue how to properly install baffles. That leaves 750 that have a clue. Good luck finding one. When it comes to repairing a problem, I say it a little differently: "Pay me now, or pay me later; the problem is not going to go away." --- I say, "If a job isn't worth doing, it isn't worth doing twice." Get it right the first time. ________________________________ From: FLYaDIVE Sent: Mon, November 8, 2010 4:12:43 PM Subject: Re: TeamGrumman-List: Cylinder woes Hi Gary: I don't know if I am being that unreasonable when it comes to Lycoming. They are the Fathers of the industry and my thoughts just keep telling me they should be much further on in development and quality then they are. It always seems it is the lawyers that hold back the development. Things like the Oil Pump Gears... How many Millions did that cost aviation. Not them... ME the little guy had to foot that bill. And remember how much ware there was in the aluminum gear? I still have mine and NONE is the answer. Then you may recall there was the sinted gear for the oil pump. Well, any engineer I know would NEVER even suggest such a thing. And lets not forget the rocker arm ... An INTAKE and an EXHAUST and don't you mix them up... Oil will be squirting the wrong direction when it comes to the EXHAUST and YES, I lost a cylinder because of that. NO! ! ! I WAS NOT THE ONE THAT INSTALLED THEM INCORRECTLY. Paperwork indicated it was Lycoming, that did the last work on the engine. Yes, I know the paperwork could very easily be wrong. I eliminated the mix up on rockers completely - I made ALL the rockers EXHAUST rockers. I understand Lycoming did that also? There are other AD's that luckily I escaped only after pulling the cowl off to check part numbers and serial numbers; others did not escape so cheaply. I would not say I have a hard-on from them. Quite the opposite. They make me go limp. I believe in Competition, I believe in keeping the work right here in the USA. I also like to support the underdog and if you think of it. The underdog has an advantage. They can learn from Lycoming. I really liked the idea that Superior had and did with hard-coat anodizing the fin area of the cylinders. No Paint to hold heat in. Better casting without flashing. And I am still waiting for more oil to be delivered to the heads. Gary, I respect your knowledge and all your experimentation. So it is NOT a personal thing between you and I. AND from your experience I am learning. It is just that Lycoming has not given me the Warm & Fuzzy feeling, only a lighter wallet. I am NOT totally against Lycoming, maybe with your teachings I may see things in a different light. ========= I feel you can learn many things from stories. I also enjoy your stories. My first thought was WHO did the overhaul? The people at Palo Alto or Lycoming? My second thought was: She is fixating on the numbers and not the situation. Everyone would like a quick - cheep cure to low compression. And I have to ask... Sorry Gary... Why did the block crack? I'm twisting the knife here and it is NOT fair. A cracked block is far from normal and not something that can be blamed on Lycoming. And if the crank was scored there must have been quite a bit of heat. Maybe before she purchased the plane and as you said: " I just couldn't convince her that the engine did not really get a real overhaul." And I agree, you do get what you pay for. But you should not have to pay too much. When it comes to repairing a problem, I say it a little differently: "Pay me now, or pay me later; the problem is not going to go away." Smiles Gary, Barry On Mon, Nov 8, 2010 at 1:57 PM, Gary Vogt wrote: Barry, I don't know why you have such a hard-on for Lycoming cylinders, they are much better cylinders. No ADs to start with. I've talked to Ken at Lycon about the various cylinders. From his perspective, they are the best and they make the most power. Building 500 engines a year, including racers and air show planes, he should know. You can pay less for a cylinder, but that's what you'll get: less. > > >Since the labor costs the same to remove and replace a $200 overhauled cylinder >as it does to replace an $1100 new cylinder, the only advantage is, you won't >have to replace the new cylinder in a hundred hours. > > >Oh, good, I feel a story coming on . . . . > > >A few years back, I had a customer with a new, to her, 1976 Tiger. Her primary >reason for picking this plane was that it had an overhauled engine. Yep, only >125 hours since complete overhaul. The compressions were in the low to mid 70s. > It leaked oil at the case parting line. And, in flight, it felt very weak. > > >Fast forward 2 years and 175 hours. Compressions were low 40s on 2 cylinders >and the other two were mid 60s. "It still feels like it's flying fine." she >would tell me. "The guys in Pali, (her vernacular for Palo Alto) told me I must >have stuck rings. They said I should soak the cylinders in Mouse Milk and then >(some other solvent I can't remember)." > > >So, for 2 weeks, I kept they cylinders full and pulled the engine through a full >four cycles everyday. Then refilled, repeated, then refilled. What the hell, I >charged her an hour a day for 2 weeks. It was her choice. I just couldn't >convince her that the engine did not really get a real overhaul. She kept >insisting, "It only has 300 hours since major overhaul!" > > >After 2 weeks, there was no change in the compressions. I ran the engine and >high speed taxied it for an hour. Checked again. No change. (oh, by-the-way, >these were the instructions the guys in Palo Alto wanted me to follow. It was >her money.) > > >I pulled the cylinders to send them to LyCon. The block was cracked at the >alternator mounting boss. Over the last year, when she brought it in for an oil >change, I thought there was a lot of oil. (I had changed the #4 oil drain back >tube the oil change prior because it was corroded through and leaking a lot. I >thought that was the source of the oil). > > >When I called her and told her that her engine block was cracked she responded >with, "How can that be? It only has 300 hours since major overhaul." I got her >a deal on an overhauled engine directly from Lycoming for under $19,000. Her >response, "The guys in Pali said I can have the block welded for a couple of >hundred dollars." So, I put her plane back together and sent her on her way. > > >A year later she flew to Auburn for a fly-in. I asked about the engine. Turns >out, during the tear down to get at the crack, they found bent rods, a bad cam, >bad lifters, and the crank was scored. Oh, yea, all of the cylinders were so >badly cracked they couldn't be repaired. Putting the engine back together cost >her . . . . . drum roll . . . . $19,000. And 6 months. > > >When she called for an annual, I had to reply with, "I would love to work on >your plane but, I'm not the right mechanic for you. Have the guys in Pali work >on your plane." > > >Bottom line: You get what you pay for. > > ________________________________ From: FLYaDIVE >To: teamgrumman-list@matronics.com >Sent: Mon, November 8, 2010 5:15:27 AM >Subject: TeamGrumman-List: Cylinder woes > >Dj: > > >Not > _blank">www.aeroelectric.com .com" target="_blank">www.buildersbooks.com >="_blank">www.homebuilthelp.com _blank">http://www.matronics.com/contribution >st" target="_blank">http://www.matronics.com/Navigator?TeamGrumman-List >tp://forums.matronics.com > -- Barry "Chop'd Liver" ________________________________ Message 2 _____________________________________ Time: 10:45:17 AM PST US From: Gary Vogt Subject: TeamGrumman-List: Fw: THE FOCKE-WULF Fw 190 FLIES AGAIN ----- Forwarded Message ---- From: Ronald Millman CPA Sent: Tue, November 9, 2010 8:26:17 AM Subject: Fw: THE FOCKE-WULF Fw 190 FLIES AGAIN ----- Original Message ----- From: Al Slayton Sent: Monday, November 08, 2010 9:31 PM Subject: FW: THE FOCKE-WULF Fw 190 FLIES AGAIN Thanks to Al Slayton for this video. The FW 190 was called the "Wurger" or Butcher Bird by the German Luftwaffe. It appeared later in WWII with it's air cooled radial engine and wide set landing gear. This made for more reliability and better ground handling than the Me109. Ron Millman. ________________________________ Here comes another "replica". Subject: THE FOCKE-WULF Fw 190 FLIES AGAIN >Go to full screen to really enjoy this 7 minute video. > >>THE FOCKE-WULF Fw 190 FLIES AGAIN >>This video was shot at the Breitscheid, Germany Air Show held >>on 21 >>and 22 August 2010. Appearing at the show were an Fw 190A-8/N, >>a >>Junkers Ju 52, a Messerschmitt Bf 109, a Grumman TBM Avenger >>registered in Switzerland, a Vickers-Supermarine Spitfire PR >>Mk. 19, >>a North American B-25 and P-51D Mustang and a Soviet Yak 11. >>The >>Mustang is parked next to the Fw 190 as you can see when the Fw >>190 >>pilot parks it. But this video shows the Fw 190A-8/N. >> >>So what is an Fw 190A-8/N? Starting in 1997 a small German >>company, >>Flug Werk GmbH, began work on a new Fw 190A-8. These planes are >>new >>builds from the ground up, using many original dies, plans, and >>other >>information from the war. Werk numbers continued from where >the >>German war machine left off with the new Fw 190A-8 labeled Fw >>190A-8/N (N for Nachbau: "replica"). >>Some of these new Fw 190s are >>known to be fitted with the original tail wheel units from the >>Second >>World War; a small cache of tail gear having been discovered. >>In >>November 2005, the first flights were completed. Ironically, >>since >>the BMW 801 engines are no longer available, a Chinese >licensed >>Russian engine, the ASh-82FN 14-cylinder twin-row radial >>engine, >>which powered some of the Fw 190s opposition: the La-5 and >>La-7, >>powers the new Fw 190A-8/N. >> >>http://www.clipwings.com/index.php?command=show_video&video_id=1021 >>__._,_.___ >> >> >> >> >> Checked by AVG - www.avg.com 07:34:00 ________________________________ Message 3 _____________________________________ Time: 04:06:05 PM PST US Subject: Re: TeamGrumman-List: Cylinder woes From: FLYaDIVE Hi Gary: I'm not discriminatory. I dislike ALL of Lycoming ;-) Cylinders, Gears, Crankshafts and Cams. I have embedded my other response within the body of your email On Tue, Nov 9, 2010 at 1:33 PM, Gary Vogt wrote: > Well, Barry, > > What are we talking about here? Gears? or Cylinders? > > As for the gears, how many out right failures where there? Not many. > [Barry] - I agree 100% with you NOT MANY. That is my point. There was NO reason to force a replacement. The ONLY gears that SHOULD have been replace AT Lycoming's expense should have been the sintered gears. > For the most part, the bottom end of any Lycoming engine will run > seemingly forever with a bad cam, bent rods, and a crank that needs to be > turned. IF the engine has been taken care of regarding oil changes and > regular use, the bottom end is good for 4000 hours. > > Rockers: Here, I'd have to agree 100%. Two nearly identical rockers with > no stamping showing how they go in. In 1984, I was doing a very thorough > annual on my first Cheetah. The engine had 600 hours on it since new. The > rocker cover gaskets were leaking, so, I decided to change them. In the > process, with a brand new Lycoming overhaul manual in hand, I decided to do > a dry tappet clearance check, just for shits-n-grins. Inside the > maintenance hangar, about 20 yards from the main FBO, I started carefully > removing all the parts. On the work bench, I laid out everything in the > order I removed them. During the cleaning process, I noticed a there was a > difference between the rockers. Strange this was, from the factory, one > side of the engine was one way, the other side was different. I asked the > mechanic there, Jack, a guy who had been working on planes for some 30 > years, which was which. He said, and I quote, "I don't know. I've never > noticed a difference before." I called Lycoming and talked to an engineer. > He didn't know either. Several transfers later, I got an answer. > > Do you know the logic behind the different rockers? The squirter is > supposed to squirt oil on the valve stem . . . exhaust only to help cool > the valve. The other one is supposed to dribble oil onto the rocker . . . . > intake only. These engines have no oil seal on the valve stems. Squirting > oil on the intake only makes oil go into the intake port, coat the inside > with residue, and burn more oil. > [Barry] - Yes, I am very familiar with how to determine which rocker goes where. The way you describe the the NO SEAL condition on the valve stem is what I was thinking about... My thought process was: If the oil squirted on the stem BURNS and COKES the stem must be HOT. So, if I could lower the temps of the valve stem I would not get burning and coking. The MORE oil to the head would lower those temps. The idea seems to fit the logic BUT I have no real numbers to work with. As I mentioned I did replace ALL the rockers with Exhaust Rockers. And I understand Lycoming has done the same thing. Makes sense as it would also reduce inventory and chance of mix-up. > Waiting for more oil to be delivered to the heads: This is a major > misconception. Born, in part, by Bill Scott and Bill Marvel. Sodium filled > valves were first used almost 100 years ago. By the mid 30's there was a > lot of research being done on sodium filled valves. Why? Because, at the > time, rockers were out in the open. Sodium filled valves offered a way to > shed heat without much oil. In fact, research done by Samuel Heron in the > late teens, early 20s, showed that excess oil on the valve causes valve > sticking. And, if you think that sticking valves are unique to Lycomings, > you haven't kept up on the valve problems (using solid valves and lots of > oil) in Continental engines. Do a little research regarding oil on sodium > filled valves. The problem is really due to the geometry of the > rocker/valve stem during operation. The side loads on the valve cause the > guide to be worn excessively*. This is true of ALL engines without roller > rockers. In this respect, the solid lifter engines (i.e., O235) are better. > Ideally, you want to get roller rockers to get rid of the side loads. Hot > Rod magazine had an excellent article on valve geometry not long ago. > > * this is THE reason why I recommend a top overhaul with new cylinders at > 1000 hrs. I've pulled a lot of cylinders with 1000 to 1500 hours on them. > I send them to Ken for tear down and inspection. I pay for the research on > this one. In every case, the cylinders have cracks in the exhaust port. > Most, but not all, show excess wear in the guides. The ones that don't > show no correlation between them. (that is, without getting Charlie Epps to > do a math analysis of it.) It just isn't worth patching the cylinder to get > another 1000 hours out of it. It'll never make it. > [Barry] - Gary, I am lacking experience of the ages in this area (You Old Fart ;-) ). You have posted a few times that you see cylinders with 1000 to 1500 Hours on them. The limited experience I have in this area and ONLY from reading Logbooks is cylinders usually last 500 to 600 Hours, before a Top is required. I know there are thousands of reasons why, but... Is there any advice or information you can offer to reach 1000 Hours? > Fins on Superior engines: Now, I ask, was that a work of art or what? > Really pretty weren't they. Problem was, those machined heads (in place of > cast heads) gave up 30% of the surface area needed to shed heat. > > [Barry] - When you say 30% less surface area. How is that calculated, 30% less fin count or smaller fins? I wonder how much cooling was gained since the fins were NOT painted? Casting flashings: I ground out the flashings on about a half dozen > engines. All with JPI engine analyzers. No change. Sloppy workmanship, > for sure, but not critical. The new heads are a whole lot better. > > [Barry] - You may have seen one of my posts from years back and recently re-posted about an RV6 that I did a fin clean-up on. We saw 40 F drop in CHT. The CHT instrument is a Grand Rapids with screw in probes. This in no way is what I expected or would cal typical. Of course temperature is a fleeting thing and OAT has an effect but CHT's now do NOT go above 400 F. Later Gary, Barry ________________________________ Message 4 _____________________________________ Time: 04:14:59 PM PST US Subject: Re: TeamGrumman-List: Cylinder woes From: FLYaDIVE WOW ! ! ! Gary, That crack is impressive. A dirty engine would surely hide that very easily. HMmmmmmm, I'm working on finding an oil leak on an AA-1 with an O-320. You just gave me another location to look at. And GUAD! Trying to find a leak on a dirty engine is like trying to find Georgia Mud on a South Carolina pig. Barry ________________________________ Message 5 _____________________________________ Time: 06:47:03 PM PST US From: Gary Vogt Subject: Re: TeamGrumman-List: Cylinder woes [Barry] - When you say 30% less surface area. How is that calculated, 30% less fin count or smaller fins? I wonder how much cooling was gained since the fins were NOT painted? The cast fins are not smooth. The roughness adds surface area. Machines fins have less area. ________________________________ From: FLYaDIVE Sent: Tue, November 9, 2010 4:03:39 PM Subject: Re: TeamGrumman-List: Cylinder woes Hi Gary: I'm not discriminatory. I dislike ALL of Lycoming ;-) Cylinders, Gears, Crankshafts and Cams. I have embedded my other response within the body of your email On Tue, Nov 9, 2010 at 1:33 PM, Gary Vogt wrote: Well, Barry, > > >What are we talking about here? Gears? or Cylinders? > > >As for the gears, how many out right failures where there? Not many. [Barry] - I agree 100% with you NOT MANY. That is my point. There was NO reason to force a replacement. The ONLY gears that SHOULD have been replace AT Lycoming's expense should have been the sintered gears. For the most part, the bottom end of any Lycoming engine will run seemingly forever with a bad cam, bent rods, and a crank that needs to be turned. IF the engine has been taken care of regarding oil changes and regular use, the bottom end is good for 4000 hours. > > >Rockers: Here, I'd have to agree 100%. Two nearly identical rockers with no >stamping showing how they go in. In 1984, I was doing a very thorough annual on >my first Cheetah. The engine had 600 hours on it since new. The rocker cover >gaskets were leaking, so, I decided to change them. In the process, with a >brand new Lycoming overhaul manual in hand, I decided to do a dry tappet >clearance check, just for shits-n-grins. Inside the maintenance hangar, about >20 yards from the main FBO, I started carefully removing all the parts. On the >work bench, I laid out everything in the order I removed them. During the >cleaning process, I noticed a there was a difference between the rockers. > Strange this was, from the factory, one side of the engine was one way, the >other side was different. I asked the mechanic there, Jack, a guy who had been >working on planes for some 30 years, which was which. He said, and I quote, "I >don't know. I've never noticed a difference before." I called Lycoming and >talked to an engineer. He didn't know either. Several transfers later, I got >an answer. > > >Do you know the logic behind the different rockers? The squirter is supposed >to squirt oil on the valve stem . . . exhaust only to help cool the valve. The >other one is supposed to dribble oil onto the rocker . . . . intake only. > These engines have no oil seal on the valve stems. Squirting oil on the intake >only makes oil go into the intake port, coat the inside with residue, and burn >more oil. [Barry] - Yes, I am very familiar with how to determine which rocker goes where. The way you describe the the NO SEAL condition on the valve stem is what I was thinking about... My thought process was: If the oil squirted on the stem BURNS and COKES the stem must be HOT. So, if I could lower the temps of the valve stem I would not get burning and coking. The MORE oil to the head would lower those temps. The idea seems to fit the logic BUT I have no real numbers to work with. As I mentioned I did replace ALL the rockers with Exhaust Rockers. And I understand Lycoming has done the same thing. Makes sense as it would also reduce inventory and chance of mix-up. > >Waiting for more oil to be delivered to the heads: This is a major >misconception. Born, in part, by Bill Scott and Bill Marvel. Sodium filled >valves were first used almost 100 years ago. By the mid 30's there was a lot of >research being done on sodium filled valves. Why? Because, at the time, >rockers were out in the open. Sodium filled valves offered a way to shed heat >without much oil. In fact, research done by Samuel Heron in the late teens, >early 20s, showed that excess oil on the valve causes valve sticking. And, if >you think that sticking valves are unique to Lycomings, you haven't kept up on >the valve problems (using solid valves and lots of oil) in Continental engines. > Do a little research regarding oil on sodium filled valves. The problem is >really due to the geometry of the rocker/valve stem during operation. The side >loads on the valve cause the guide to be worn excessively*. This is true of ALL >engines without roller rockers. In this respect, the solid lifter engines >(i.e., O235) are better. Ideally, you want to get roller rockers to get rid of >the side loads. Hot Rod magazine had an excellent article on valve geometry not >long ago. > > >* this is THE reason why I recommend a top overhaul with new cylinders at 1000 >hrs. I've pulled a lot of cylinders with 1000 to 1500 hours on them. I send >them to Ken for tear down and inspection. I pay for the research on this one. > In every case, the cylinders have cracks in the exhaust port. Most, but not >all, show excess wear in the guides. The ones that don't show no correlation >between them. (that is, without getting Charlie Epps to do a math analysis of >it.) It just isn't worth patching the cylinder to get another 1000 hours out of >it. It'll never make it. [Barry] - Gary, I am lacking experience of the ages in this area (You Old Fart ;-) ). You have posted a few times that you see cylinders with 1000 to 1500 Hours on them. The limited experience I have in this area and ONLY from reading Logbooks is cylinders usually last 500 to 600 Hours, before a Top is required. I know there are thousands of reasons why, but... Is there any advice or information you can offer to reach 1000 Hours? > >Fins on Superior engines: Now, I ask, was that a work of art or what? Really >pretty weren't they. Problem was, those machined heads (in place of cast heads) >gave up 30% of the surface area needed to shed heat. > > [Barry] - When you say 30% less surface area. How is that calculated, 30% less fin count or smaller fins? I wonder how much cooling was gained since the fins were NOT painted? Casting flashings: I ground out the flashings on about a half dozen engines. All with JPI engine analyzers. No change. Sloppy workmanship, for sure, but not critical. The new heads are a whole lot better. > > [Barry] - You may have seen one of my posts from years back and recently re-posted about an RV6 that I did a fin clean-up on. We saw 40 F drop in CHT. The CHT instrument is a Grand Rapids with screw in probes. This in no way is what I expected or would cal typical. Of course temperature is a fleeting thing and OAT has an effect but CHT's now do NOT go above 400 F. Later Gary, Barry ________________________________ Message 6 _____________________________________ Time: 06:49:15 PM PST US From: Gary Vogt Subject: Re: TeamGrumman-List: Cylinder woes [Barry] - Yes, I am very familiar with how to determine which rocker goes where. The way you describe the the NO SEAL condition on the valve stem is what I was thinking about... My thought process was: If the oil squirted on the stem BURNS and COKES the stem must be HOT. So, if I could lower the temps of the valve stem I would not get burning and coking. The MORE oil to the head would lower those temps. If you have too much, you will have excess coking and sucking oil into the intake. ________________________________ From: FLYaDIVE Sent: Tue, November 9, 2010 4:03:39 PM Subject: Re: TeamGrumman-List: Cylinder woes Hi Gary: I'm not discriminatory. I dislike ALL of Lycoming ;-) Cylinders, Gears, Crankshafts and Cams. I have embedded my other response within the body of your email On Tue, Nov 9, 2010 at 1:33 PM, Gary Vogt wrote: Well, Barry, > > >What are we talking about here? Gears? or Cylinders? > > >As for the gears, how many out right failures where there? Not many. [Barry] - I agree 100% with you NOT MANY. That is my point. There was NO reason to force a replacement. The ONLY gears that SHOULD have been replace AT Lycoming's expense should have been the sintered gears. For the most part, the bottom end of any Lycoming engine will run seemingly forever with a bad cam, bent rods, and a crank that needs to be turned. IF the engine has been taken care of regarding oil changes and regular use, the bottom end is good for 4000 hours. > > >Rockers: Here, I'd have to agree 100%. Two nearly identical rockers with no >stamping showing how they go in. In 1984, I was doing a very thorough annual on >my first Cheetah. The engine had 600 hours on it since new. The rocker cover >gaskets were leaking, so, I decided to change them. In the process, with a >brand new Lycoming overhaul manual in hand, I decided to do a dry tappet >clearance check, just for shits-n-grins. Inside the maintenance hangar, about >20 yards from the main FBO, I started carefully removing all the parts. On the >work bench, I laid out everything in the order I removed them. During the >cleaning process, I noticed a there was a difference between the rockers. > Strange this was, from the factory, one side of the engine was one way, the >other side was different. I asked the mechanic there, Jack, a guy who had been >working on planes for some 30 years, which was which. He said, and I quote, "I >don't know. I've never noticed a difference before." I called Lycoming and >talked to an engineer. He didn't know either. Several transfers later, I got >an answer. > > >Do you know the logic behind the different rockers? The squirter is supposed >to squirt oil on the valve stem . . . exhaust only to help cool the valve. The >other one is supposed to dribble oil onto the rocker . . . . intake only. > These engines have no oil seal on the valve stems. Squirting oil on the intake >only makes oil go into the intake port, coat the inside with residue, and burn >more oil. [Barry] - Yes, I am very familiar with how to determine which rocker goes where. The way you describe the the NO SEAL condition on the valve stem is what I was thinking about... My thought process was: If the oil squirted on the stem BURNS and COKES the stem must be HOT. So, if I could lower the temps of the valve stem I would not get burning and coking. The MORE oil to the head would lower those temps. The idea seems to fit the logic BUT I have no real numbers to work with. As I mentioned I did replace ALL the rockers with Exhaust Rockers. And I understand Lycoming has done the same thing. Makes sense as it would also reduce inventory and chance of mix-up. > >Waiting for more oil to be delivered to the heads: This is a major >misconception. Born, in part, by Bill Scott and Bill Marvel. Sodium filled >valves were first used almost 100 years ago. By the mid 30's there was a lot of >research being done on sodium filled valves. Why? Because, at the time, >rockers were out in the open. Sodium filled valves offered a way to shed heat >without much oil. In fact, research done by Samuel Heron in the late teens, >early 20s, showed that excess oil on the valve causes valve sticking. And, if >you think that sticking valves are unique to Lycomings, you haven't kept up on >the valve problems (using solid valves and lots of oil) in Continental engines. > Do a little research regarding oil on sodium filled valves. The problem is >really due to the geometry of the rocker/valve stem during operation. The side >loads on the valve cause the guide to be worn excessively*. This is true of ALL >engines without roller rockers. In this respect, the solid lifter engines >(i.e., O235) are better. Ideally, you want to get roller rockers to get rid of >the side loads. Hot Rod magazine had an excellent article on valve geometry not >long ago. > > >* this is THE reason why I recommend a top overhaul with new cylinders at 1000 >hrs. I've pulled a lot of cylinders with 1000 to 1500 hours on them. I send >them to Ken for tear down and inspection. I pay for the research on this one. > In every case, the cylinders have cracks in the exhaust port. Most, but not >all, show excess wear in the guides. The ones that don't show no correlation >between them. (that is, without getting Charlie Epps to do a math analysis of >it.) It just isn't worth patching the cylinder to get another 1000 hours out of >it. It'll never make it. [Barry] - Gary, I am lacking experience of the ages in this area (You Old Fart ;-) ). You have posted a few times that you see cylinders with 1000 to 1500 Hours on them. The limited experience I have in this area and ONLY from reading Logbooks is cylinders usually last 500 to 600 Hours, before a Top is required. I know there are thousands of reasons why, but... Is there any advice or information you can offer to reach 1000 Hours? > >Fins on Superior engines: Now, I ask, was that a work of art or what? Really >pretty weren't they. Problem was, those machined heads (in place of cast heads) >gave up 30% of the surface area needed to shed heat. > > [Barry] - When you say 30% less surface area. How is that calculated, 30% less fin count or smaller fins? I wonder how much cooling was gained since the fins were NOT painted? Casting flashings: I ground out the flashings on about a half dozen engines. All with JPI engine analyzers. No change. Sloppy workmanship, for sure, but not critical. The new heads are a whole lot better. > > [Barry] - You may have seen one of my posts from years back and recently re-posted about an RV6 that I did a fin clean-up on. We saw 40 F drop in CHT. The CHT instrument is a Grand Rapids with screw in probes. This in no way is what I expected or would cal typical. Of course temperature is a fleeting thing and OAT has an effect but CHT's now do NOT go above 400 F. Later Gary, Barry ________________________________ Message 7 _____________________________________ Time: 06:55:05 PM PST US From: Gary Vogt Subject: Re: TeamGrumman-List: Cylinder woes I had a plane come in that was covered with oil. I took off everything tha t =0Acould come off and started cleaning everything. All of the oil drain back hoses =0Awere AFU. A couple drain back tubes were leaking at the fitt ing. The oil =0Apan/sump was leaking. The rockers were leaking. The push rod tubes and the =0Acylinders were leaking.=0A=0A=A2 replaced the h oses and drain back tube fitting on the cylinders.=0A=A2 replaced the "O" rings on the cylinders=0A=A2 replaced the push rod tube seals. =0A=A2 replaced the rocker cover gaskets.=0A=A2 when I got to t he sump, I noticed that part of the original gasket was still =0Aon the sum p. Whoever overhauled the engine, paid no attention to sealing it.=0A=0ATh e engine had 120 hours on it since major overhaul.=0A=0A=0A=0A_____________ ___________________=0AFrom: FLYaDIVE =0ATo: teamgrumman -list@matronics.com=0ASent: Tue, November 9, 2010 4:12:43 PM=0ASubject: Re: TeamGrumman-List: Cylinder woes=0A=0AWOW ! ! ! =0A=0AGary, =0A=0AThat cra ck is impressive. =0A=0AA dirty engine would surely hide that very easily. =0A=0AHMmmmmmm, I'm working on finding an oil leak on an AA-1 with an O-320 . You just =0Agave me another location to look at.=0AAnd GUAD! Trying to find a leak on a dirty engine is like trying to =0Afind Georgia Mud on a So ===================== =0A=0A=0A =0A ________________________________ Message 8 _____________________________________ Time: 11:03:26 PM PST US From: Gary Vogt Subject: TeamGrumman-List: brakes OK, how would this happen? ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message teamgrumman-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/TeamGrumman-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/teamgrumman-list Browse Digests http://www.matronics.com/digest/teamgrumman-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.