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rgruen
10-17-2011, 02:22 PM
Any suggestions as to how to perform this operation?

Thanks,

RG

Hiperbiper
10-18-2011, 08:03 AM
Any suggestions as to how to perform this operation?

Thanks,

RG

What airplane and why do you think it needs balancing?

Chris

BMW rider
10-19-2011, 05:07 PM
Any suggestions as to how to perform this operation?

Thanks,

RG

I balance all our motorcycle wheels / tires using a simple stand with 2 sets of slightly overlapping sealed ball bearings. The two sets of bearings must be far enough apart that the tire fits between them. An axle passes through the wheel bearings and rests on either side so that the axle can rotate. (Think ferris wheel) Quarter ounce stick on wheel weights are then temporary taped on the inside flange of the rim to balance. Move the wheel 90 degrees after it settles and determine the correct weights so that it will rest anywhere in rotation. Then replace the temorary weights with new stick ons available at any motorcycle shop. My balance stand is made up of bolted slotted angle and works fine. While not perfect, this method worked fine at 175 MPH for the TZ750 I crewed at Daytona.


As a higher cost, lower effort option, you may want to check with your local independent motorcycle or tire shop to see if they can and wish to do it.
Regards,
Ralph

chintonmd
10-19-2011, 07:06 PM
Very easy to do if you know the secret:
Wash the bearings clean then lubricate with a very light oil like WD40 or similar. Put it on the axle and tighten just enough to take out the slack and no more. Then just play around with it until you find the heavy side and balance with some small weights (apply half to each side to keep it even.) You'll be surprised how sensitive the method is. Don't forget to grease the bearings again!
Chuck

Hiperbiper
10-19-2011, 08:07 PM
99% of the vibration problems I've seen on airplanes have had nothing at all to do with balance. Most have to do with a tire (or tyre) being out-of-round!
Our airplane tires are old bias ply designs not changed much since the 1940's...anyone who learned to drive in the 1950's was warned against hitting potholes and running up on curbs due to the inheriant weakness of bias ply tires which allowed tires to go "out-of-round" and cause a rough ride; landing an airplane hard does the same thing...even sitting too long would cause a tire to flat spot; never to run smooth again!
So before looking for a balance problem prop up the wheel and give it a spin...look for a wobble or an egg shaped runout. If you can see anything but a smooth round run you have a broken ply and no amount of balancing is going to help.

Hope this helps.

Chris

romarietta
10-20-2011, 06:31 PM
In the 80's, I balanced the tires on my EZ, vezly.
I purchased a round bubble level from Sears.
Fill the bath tub with water to a level that the tires will float.(I left the bearings in, they did not get wet).
Place the round bubble level over the axle hole.
I used stick on mag wheel weights cut to different sizes to balance by placing them on the wheel.
Once balanced, I stuck them on the wheel and rechecked the balance.
Worked great...............

uavmx
10-22-2011, 04:45 PM
Yeah, I would have to argue that balancing does nothing for aircraft that take off and land at 60-80 mph (if that) and are only doing a takeoff roll for 30 seconds.....

Bill Greenwood
10-23-2011, 11:40 AM
uavmx, I had a tire change on my Bonanza, and it was then rough on takeoff. I really disagree with your point that inbalance does not matter. I lift off at 80mph, but if the tire is rough for that time, there are two bad things, First, any shaking can mask a possible engine problem, that is you won't know if it is only the tire until you are in the air. Also any shaking feels bad to the passengers, even if not the pilot. And any shaking causes possible wear and tear on everything in the plane, from instruments to airframe parts and can cause cracks. Obviously not as bad as a prop out of balance because it is short duration, but why have any out of balance when tire balance is easy and not too expensive to correct.
To diagnose a tire being out, notice if it is rough on the roll, but lessens as you lift off. After lift off you can tap the brakes,and it it smooths out then it was a wheel or tire. Tap one brake at a time to see which wheel.

Dr.Bob
10-24-2011, 02:51 PM
Any suggestions as to how to perform this operation?

Thanks,

RG I am constantly amazed at how many ignorant pilots there are in private aviation. My Varieze first flew in 1978, and was built to spec with no modifications when I purchased it 17 years ago. It still had the original super soft main gear, which vibrated front and back badly if the tire pressure was over 35 lbs. After my 1st landing I noticed the tires weren't balanced, so I immediately balanced the tires, thinking that was the entire problem. It helped tremendously and I had no problems with further vibration as long as the pressure was under 35 lbs. It was years later when I realized that no single engine airplanes of any kind had their tires balanced. So it is not surprising to me when I hear comments that it is not necessary to balance aircraft tires, because they are so small or you're only on the ground for 30 seconds or so. Because, EVERY, single engine airplane that everybody has ever flown has vibrated mildly or severely at some point on landing and takeoff ! Try dropping your car at 300 mph on the Bonneville Salt Flats from the height of 1 foot with unbalanced tires. How bad do you think it would vibrate ? Airplane tires are 1/5th to half the diameter of a car tire, so they spin at a much higher RPM and are thus much more susceptible to out of balance vibrations. The front castering wheel on all EZ's and Velocity's are like those little Gyroscope toys we played with as kids, except multiplied by the power of 10. Remember when you spun the Gyro toy and tried to move it off its center, and how out of control it got jumping out of your hand ? Why do we balance ailerons and elevators ? What has taken place in the canard community over the years to solve the fork and front wheel breakage problem, is to make them BIGGER and HEAVIER, which only amplifies the problem. The parts usually survived, but the vibrations got bigger. I've seen front bulkheads ripped out of Velocity's, because of this imbalance problem. And it is so EASY to fix. I just balanced all 3 tires on a 540 Velocity XL, and the test pilot was amazed at what a difference it made. I recently took a fellow Varieze pilot for a ride in my plane;( he flys a Citation for a living ) and he didn't think he needed his tires balanced, until we landed. "You've got to balance my tires", were the 1st words out of his mouth, as we touched down on what felt like a velvet bed. Bubble balancers won't due, it has to be a spin balancer. It is not that difficult to perform, but it is a skill that must be properly taught. Many seem concerned about the wheel weights coming off. This will NEVER happen if the balancer knows how to attach them. I am now performing this service on ANY aircraft tire. So if you want to have safer landings and takeoffs, and stop your teeth from rattlling, just ship me your mounted wheels and tires and bearings, or find a racing go-kart shop and have them balance them for you. I have also developed tubeless wheels for the new Aero 4.00 & 5.00 -5 tires, which allow you to run lower tire pressures that will shorten your landing roll out distance by as much as 2/3's, and doulble the life of your tires.If you have any questions, please contact me at (818)485-7311 or fw190prop@hotmail.com Dr.Bob

rgruen
10-24-2011, 08:24 PM
I was the original poster on this topic.Tthanks for all the replies. Wow, I seem to have opened an interesting topic! I get a vibration after nose whell lifts off. Wheel is going at max rpm then, and it needs to be balanced. SO I am reading with great interest all that has been posted. I would like to just take it to a local tire store and have it dynamically done, but they do not do these smaller wheels. [or I have nopt found a place that does].

Thanks for all the input.

Rupert Gruen
Pelican PL 914 C-GRPW Kelowna BC Canada

uavmx
10-25-2011, 03:44 AM
I'm not saying that balancing should never be accomplished. But if pilots are experiencing MAJOR vibrations from what they suspect to be an out of balance tire, I would be questioning other things that you may be covering up by balancing.

Everyone like stories so here's my inverse story to yours. Our bonanza that we purchased and flew for a while before deciding to change out the tires had no noticeable vibration, never questioned it. The tires had been previously balanced, and since the paint was in bad shape, I decided to completely strip them down to bare metal, inspect, repaint, new tubes and tires (of high quality) and ended up changing out most of the bearings and a couple of the races. I pulled the balancing weights off because I needed to strip it down. I reassembled the tires properly. Re-installed WITHOUT balancing and have been flying for 2 years now with no vibrations.

Now my argument is all the other factors besides the tire being out of balance are:
-Quality tire and tube of the correct size
-Condition of bearings and races (Corrosion on the races, flat spots on the bearing, slop in the bearing, etc)
-Condition of the wheel itself-Installing the tire and tube correctly (did you line up the valve stem in the right spot? Are there any folds in the tube?)
-Installing the wheel assembly onto the aircraft properly. (proper torques, does the bearing fit properly on the axle itself?)
-Is your shimmy damper in good condition? Condition of your struts, attachment points, hinge joints, play in the landing gear,etc (slight vibration causing larger vibrations?)

If any one of those above things are incorrect and causing your tire to be out of balance, isn't balancing just masking? If everything comes down to being correct, and all the above looks good and is right, then there may be an imbalance of your wheel itself. The quality of your wheel could be poor or the indexing is off. I would check the balance of the wheel by itself. Maybe by rotating the wheel halves over a hole or two (as long as it's not an indexed wheel) it then puts your wheel itself into balance. Don't you think the manufacturers of the wheels and tires are concerned about balance and provide products that are at least damn close to being balanced? The aircraft I work on for work is extremely sensitive to vibrations, takes off and lands at 100mph and we do no balancing of the tires and have never noticed or have been concerned.I think people obsess over the idea of balancing, and may be over looking other issues that by balancing you are masking. Now with all those things done, and your wheel is just out of balance and there is nothing you can do besides buying a new wheel, then by all means balance (motorcycle shop would probably work out the best.) But I don't think it's a quick and easy YES BALANCE answer. If one of my clients was concerned about vibrations, there would be a lot of other places I would look first.

Justin
A&P/IA

rosiejerryrosie
10-25-2011, 04:00 AM
I am constantly amazed at how many ignorant pilots there are in private aviation.

Now THAT's a way to make friends and influence people!!!

flyingriki
10-25-2011, 08:00 AM
Whatever you do, DON'T ask him about using Mobile 1 in your Lycoming.......!

The problem he does address correctly is the wheels on EZs are very small and not necessarily that precisely made. The tires are similarly simple and the balancing he does works very well on them. The arguements about not doing any good are just wrong. Has more effect on some wheel/tire combos than others.....

Dr.Bob
10-26-2011, 01:36 AM
Whatever you do, DON'T ask him about using Mobile 1 in your Lycoming.......!

The problem he does address correctly is the wheels on EZs are very small and not necessarily that precisely made. The tires are similarly simple and the balancing he does works very well on them. The arguements about not doing any good are just wrong. Has more effect on some wheel/tire combos than others.....

Yes, don't ask me about using Mobil 1 car oil in your aircraft engine. You might just double or triple your engine life ! And small EZ wheels are actually square not round, that's why they need balancing ! And UAVMX appears to be your typical high dollar certified aircraft owner that believes EVERYTHING the FAA and the factory Gods say as LAW ! An I'm sorry rosiejerryrosie that you took my comment to heart. Did I strike a nerve ? And yes some tires are not as out of balance as others and so you won't get a lot of vibration, but if you do balance your tires and you have a small vibration, you will know it is coming from somewhere else, and it might be coming from a location that could kill you. Like from under the cowl ! My friend just got his 337 Cessna flying, and after his 1st landing he said he needed to fix his shimmy damper on his front wheel, because it shook so bad. I said how much air do you have in the mains, and he said 55lbs, what the factory recommends. Retractable gear Cessnas are prone to the same gear leg shake as Long-ezs and Variezes, so I made him drop the air to 38lbs and go fly it. And he was amazed at what a difference it made. Then we balanced all 3 tires (the mains are big 6.00's flyingriki) and he couldn't believe how smooth it was on touch down. But don't take my word, read some physics books, and stop believing everything these big Corporations like Cessna, Beechcraft, Piper, Lycoming and Continental say as absolute fact when they ream you $45 for a spark plug that should cost $5 ! They keep selling us this junk that hasn't changed much in design or quality since the 1940's ! Thank god for Rutan designing a safe, fast, efficient, affordable airplane so I don't have to fly one of these slow, expensive antiques.
Dr.Bob ...fw190prop@hotmail.com

uavmx
10-26-2011, 04:29 AM
And UAVMX appears to be your typical high dollar certified aircraft owner that believes EVERYTHING the FAA and the factory Gods say as LAW !

wow, what?! I was trying to have a discussion about this topic, apparently you just want to attack people and not put forth any valid arguments. Where did I say anything of that nature? I pray to god you're not a Doctor.

A&P/IA trying to bring common sense, outside the box ("just balance everything and your problems will go away") and help bring up other ideas that should be addressed to help PEOPLE STAY SAFE and keep their aircraft SAFE.

Bring something useful to this discussion please

rosiejerryrosie
10-26-2011, 08:51 AM
An I'm sorry rosiejerryrosie that you took my comment to heart. Did I strike a nerve ?

No...but I've written you off as anyone that I'd like to meet.....

Bill Greenwood
10-26-2011, 09:37 AM
Justin, it was pretty simple on my Bonanza. I had a main tire removed at annual to replace a tube with a slow leak. The next takeoffs I notice a vibration; not severe but noticeable. It is clearly related to a tire that is rotating. The vibration is not there on runup, and it is there on takeoff roll, and it increases with speed until the liftoff about 70K. After liftoff tapping the right brake stops it right away. So I had the shop redo it and the problem went away. I suspect that the A&P was in a bit of a hurry and thought he did not have to rebalance just for a tube, but the took care of it, no charge.
Once before I had a tire changed at a quick and cheap shop, and had vibration and had to go to a better shop to balance it .Problem solved
I am not an A&P, but I have been around both car, cycle, and plane repair shops for 50 years, and was a mechanic in the A F. It seems to me to be good practice, that if you have a problem you look at the last thing that was changed,( ie the tire or tube) and also start with the simplest item first. The mechanics I use for this plane have decades of experience,and lots of satisfied customers. For another plane I use QG Aviation, who built award winners as well as a Osh grand champion, and that it the way they do things.

Dr.Bob
10-27-2011, 02:46 AM
wow, what?! I was trying to have a discussion about this topic, apparently you just want to attack people and not put forth any valid arguments. Where did I say anything of that nature? I pray to god you're not a Doctor.

A&P/IA trying to bring common sense, outside the box ("just balance everything and your problems will go away") and help bring up other ideas that should be addressed to help PEOPLE STAY SAFE and keep their aircraft SAFE.

Bring something useful to this discussion please

Attack people? Valid arguments? The fact that you do not think balancing aircraft tires & wheels is important, proves my point. Of course you need to check the tire and the bearings and races, especially if it is your typical 40 or 50 year old airplane. The problem with people that have received all their training in FAA approved A&P schools, and have no mechanical engineering or car mechanic training outside of aviation are working with blinders on. Now it's not your fault, because the people training you should know what they are talking about. If you were not taught to do certain procedures on airplanes, then it must not be necessary, because flying is a serious business, and small mistakes can kill people more easily than a car mechanics mistake can, the FAA would have told me if it was important. And that is exactly what I thought when I got into private aviation 18 years ago. I'm ex-Air Force, I'm a mechanical proto-type design engineer, I grew up in the military, my father was a pilot in the Army and he went thru WW 2, korea, and Vietnam. In the 70's & 80's I built and raced Grand Prix motorcycles and Formula cars and won several National Championships. After getting into private aviation in the early 90's I started becoming aware of some of the strange beliefs and ancient mechanical practices that were considered proper in aviation. After hearing the same ridiculous stories and beliefs that were constantly repeated by A&P's and old pilots, I finally realized certified aviation resembled more of a faith based cult than an exercise in modern engineering. Now I am not speaking of Gulfstreams or F-16's or 737's; I am talking about C-172's, and Cherokee's and Bonanza's and Lycoming's and Continentals that are stuck back in time in the 1940's. The junk we are forced to use, magnetos, carburetors, mechanical fuel injection, pressed in valve seats, paper gaskets, oil dripping everywhere. I'll leave you with my favorite voodoo aviation myth, as why Mobil 1 pulled their synthetic aviation oil from the shelves. The myth goes on to say that the lead in aviation gas congealed in the oil into little clumps and clogged up the inner workings of the engines. And I have met many A&P's that swear they saw it with their own eyes. And they say it didn't happen in cars because they use unleaded gas and cars are watercooled. Well there is a lot more lead in high octane race car gas and there were still a lot of air cooled motorcycles and porsche's racing in the 80's & 90's, and the majority of winners were using Mobil 1. And when I ask these same A&P's how the lead got in the oil, they say blowby the pistons. Well there is less than 1 gram of lead in every gallon of aviation fuel, and if you had that much blowby the piston rings, allowing it to congeal in the oil, the pistons would seize in a matter of minutes. Anyway myself and many of my friends have been using Mobil 1 synthetic automotive oil and unleaded car gas in our Continentals and Lycomings for over 14 years with little to no wear.
Goodluck, Dr.Bob....fw190prop@hotmail.com

flyingriki
10-27-2011, 10:01 AM
Bob, you have a lot to offer but initially calling many of us 'ignorant' isn't the way to start. Now if you're as smart as you seem to think - isn't that approach to starting a post sorta, well, to use your word...'ignorant' .....?

Had an interesting conversation with John at Sac Sky Ranch one day about oil. When his shop used to service fleets and the new synthetic oil came into use he said business got very brisk...... The fleets changed back right away after a lot of damage. There may have been something different about that oil then compared to the new ones but I can't afford to experiment on the basis of one wild man with a nasty vocabulary and bad attitude.
Flame on Bob.

Bill Greenwood
10-27-2011, 01:11 PM
Bob, you have some good points, but clear up one fact for me,Please.

Perhaps 10 years ago or so, didn;t Mobile get approval for airplane use of Mobile 1 fully synthetic oil and didn't they market it heavily?

Then after a year or so of use, there were a lot of airplane piston engines damaged and Mobile did take responsibility and pay for overhaul of many engines, both in line and radial?
Am I correct on this?

Did they or the FAA pull Mobile 1 off the market?

What do you believe caused the engine problems? What did Mobile say?

Dr.Bob
10-28-2011, 03:13 AM
Where do you get " nasty vocabulary and bad attitude " from ? Merriam-Webster defines ignorant as; lacking knowledge or comprehension of the thing specified. If I called people stupid morons I would understand, but like I said, I too believed the FAA and the manufacturers at 1st until I came across things that were not correct. And I only new this because of my vast experience in auto and motorcycle racing and the physics of engineering that I had been taught. I don't know John at Sac Sky Ranch, so I don't know what he experienced. But I do know a pilot that has been racing at Reno in the Formula 1 class for a long time that still uses, and has cases of that old mobil one aviation oil that they stopped selling in 1994, and he spins that 0-200 well over 4,000 RPM, and he hasn't had the problems other racers experienced using other aviation oils. I use Mobil 1 car oil and I buy 5 qt jugs for $26 at Walmart. I am just trying to help out fellow pilots with scientific knowledge that for whatever reason is suppressed or ridiculed in the aviation community. And a few of the people in this forum are not the 1st to charge me with Heresy going agsinst the Religion of certified aviation. For over 10 years I've shown people the pistons and let them look inside the lower end of my 0-200 that hasn't been apart since 1975, yet looks brand new like it was assembled yesterday, and they still won't believe. But fortunately there are people that are new to aviation that are not disciples of this strange religion that do believe in facts and science.
Dr.Bob....fw190rop@hotmail.com

Dr.Bob
10-28-2011, 04:07 AM
The Voyager used Mobil 1 aviation oil and I believe they started selling it to the public in the late 80's, and pulled it in 1994. I got out of car racing in 1986 before synthetics got really big, and I was sponsored by Castrol. I didn't even know about the problems Mobil had until are started running Mobil 1 car oil after I seized a piston on Shell. I had been having my oil analized by a company in Arizona and after the seizure I got one of their engineers to admit that aviation oil was the poorest quality of any of the oils they tested, even tractor oils he said. So I then contacted an old friend from my racing days that was now working for one of the top motorcycle drag and roadrace teams and told him what happened. He is the one that told me to use Mobil 1, because he said it didn't break down at any temperature and it made the most horsepower of any oil they had tested. So just for kicks I did a little speed run with shell after I put a new cylinder on, and landed, changed the oil, took off and my engine rpm increased by almost 300rpm and I was suddenly 4mph faster ! I couldn't believe it, because in drag racing a tenth of a second is a lot of time so I wasn't expecting the gain in horsepower that I saw. So I immediately called my friend to tell him the amazing news and he started laughing. He told me that they had dynoed every oil made and Mobil 1 was over 5hp more than the next best oil. He said if the Valvoline Nascar team was winning races, they were pouring Mobil 1 into Valvoline bottles. When I told other pilots how great Mobil 1 worked they said I was going to kill myself and told me about what happened with Mobil 1 aviation oil. The story didn't make sense so I asked my friend to talk to people at Mobil, since they were sponsored by them, and find out the real story. He said there were only 2 people initially that claimed they had problems, and their engineers said it wasn't from the oil, but these guys had a lot of money and started a class action lawsuit. And in lawsuit America, many jumped on the bad wagon hoping to get a quick buck. Mobil knew going in there was no money in aviation oil, but after Voyager's success they thought they would get some cheap publicity. But it never hurt them in the automotive field, because it works so good. I would think other synthetic oils have caught up with Mobil 1, but I have no desire or incentive to do any testing since this stuff works so good. I hate typing, so if you have any questions give me a call.
Dr.Bob (818)485-7311

uavmx
10-28-2011, 04:58 AM
Justin, it was pretty simple on my Bonanza. I had a main tire removed at annual to replace a tube with a slow leak. The next takeoffs I notice a vibration; not severe but noticeable. It is clearly related to a tire that is rotating. The vibration is not there on runup, and it is there on takeoff roll, and it increases with speed until the liftoff about 70K. After liftoff tapping the right brake stops it right away. So I had the shop redo it and the problem went away. I suspect that the A&P was in a bit of a hurry and thought he did not have to rebalance just for a tube, but the took care of it, no charge.
Once before I had a tire changed at a quick and cheap shop, and had vibration and had to go to a better shop to balance it .Problem solved
I am not an A&P, but I have been around both car, cycle, and plane repair shops for 50 years, and was a mechanic in the A F. It seems to me to be good practice, that if you have a problem you look at the last thing that was changed,( ie the tire or tube) and also start with the simplest item first. The mechanics I use for this plane have decades of experience,and lots of satisfied customers. For another plane I use QG Aviation, who built award winners as well as a Osh grand champion, and that it the way they do things.

Thanks for the meaningful insight. I would love the opportunity to look further into a case like yours. While I completely understand and believe that you had an issue and balancing fixed it, it would be fun to try to see if it could be tracked down to something else. There's no better way to prove a point then by actually going through the process. You aren't an A&P or don't do too much of your own work (which building a tire you can do as a pilot) but trying some different things with your tires/setup could be a great way to try and "prove" one side of the argument or other. Where are you located?

Unlike Bob, I would like to be scientific about it, not just make baseless claims with no facts or data. The real way to solve the argument would be to get a test bed and hook up sensors, track different tires, wheels, aircraft, etc. Would be very interesting.

Bob, you put a lot of words into a lot of peoples mouths. Your assumptions about peoples experiences, education, training and ignorance does nothing to help your case or prove your point. I'm sure you have some great ideas and thoughts. I completely agree that Aviation is archaic. There are a lot of processes and technologies used because "that's how we've always done it". There are still pilots out there that aren't comfortable with flying composite aircraft. It takes time to change ideas and integrate technologies especially with something like Aviation that is deemed such a hazardous activity. But you running out from behind a barn yelling "hey ya'll just fly mobil 1 auto oil, cus I've done it for 14 years, your all ignorant for not" is NOT how you're going to get a lot of people's attention. I'm sure you have and I'm sure it worked fine, how many people run Marvel Mystery Oil in their engines (until EAA did the great article about what's actually in it). Why don't you write an article for EAA on using auto oil in aircraft engines.

Bill Greenwood
10-28-2011, 12:01 PM
Justin, if the problem I had started with a main tire removed and new tube added, and it was verifed as to which tire bu tapping the right brake after liftoff, and then it was cured by having the shop go back and rebalance just that tire, which cured the problem. I don't see that there is much else to "track down". By the way the shop is Brungard at Boulder, Co. long time experts on Bonanzas.
I use Marvel Mystery oil in my Bonanza at the recommendation of the engine overhauler. Exhaust valve sticking and wear are major problems in large Continental engines, like my TSIO 520 UB, and the Marvel may help. I also use it in another engine wear top end, and cam wear is a problem.
I don't have any idea that there are some exotic or magic ingredients in Marvel, as far as I know it is just a light oil. But there is a half century of good use behind it, like the airlines that use to buy it by the drum when they ran radial engines.
I didnt' see the EAA article on Marvel, can you paraphrase it ? Thanks

Bill Greenwood
10-28-2011, 12:16 PM
Bob, , frankly you seem to have a bias or anger against the FAA and the legal process, like a class action lawsuit, that colors your version of this. Have you or do any of those close to you work for Mobil?

I went to Google to refresh my memory from the Av 1 problem back in 1994-96. I recall Av Consumer covered it.

Yes, not all engines seem to have been damaged by AV i. But if it was only 2 guys, with no real other evidence, I don't think Mobil would have stepped up and paid for so many engines. It is to their credit that they did, however I don't think that lawsuit was going to just go away for lack of evidence. And I don't think that major law firm would have taken on the suit, probably on a contingent fee basis, without some good evidence.

And you still haven't said what you think caused the damage in the engines that used AV 1, whether it was 2 or two thousand?

And Mobil sold and promoted the oil for use in normal use in regular airplanes. Do you think the positive example of your small race engine turning high power and high rpm for a short time, and the Voyager continuous flight of a few days without stopping, might be quite a bit different than normal use?

Dr.Bob
10-29-2011, 01:01 AM
uavmx, can you read ? And if you can, did you actually read what I said ? Get a phyics book and read the effects of a rotating mass. Do you have your tires on your car balanced ? Maybe you should 1st hook up some sensors, track different tires, wheels, cars, etc.

Dr.Bob
10-29-2011, 01:07 AM
Bill, I hate these one-way written conversations, they waste to much time. I would be happy to give you more info on all your questions, so give me a call or e-mail me your number and I'll spend my dime.

Dr.Bob (818)485-7311.....fw190prop@hotmail.com

Frank Giger
10-29-2011, 03:21 AM
Back to the topic at hand:


After liftoff tapping the right brake stops it right away.

My money is on an unbalanced tire. Maybe on a slim chance a bearing issue, but I'd check balance first.

uavmx
10-29-2011, 09:56 AM
Justin, if the problem I had started with a main tire removed and new tube added, and it was verifed as to which tire bu tapping the right brake after liftoff, and then it was cured by having the shop go back and rebalance just that tire, which cured the problem. I don't see that there is much else to "track down". By the way the shop is Brungard at Boulder, Co. long time experts on Bonanzas.
I use Marvel Mystery oil in my Bonanza at the recommendation of the engine overhauler. Exhaust valve sticking and wear are major problems in large Continental engines, like my TSIO 520 UB, and the Marvel may help. I also use it in another engine wear top end, and cam wear is a problem.
I don't have any idea that there are some exotic or magic ingredients in Marvel, as far as I know it is just a light oil. But there is a half century of good use behind it, like the airlines that use to buy it by the drum when they ran radial engines.
I didnt' see the EAA article on Marvel, can you paraphrase it ? Thanks

The article on MMO pretty much stated it's not a mystery any more because with MSDS's these days, you can find out what's in it. Two ingredients that were quite interesting was pig fat (i think that's what it was) and purple die. Pretty much it was some odd ball ingredients that were refuted to have any benefits. It was a good article, I can't find it, maybe someone can find it and scan it in? I believe the author was Mike Busch. You know what, now that I think about it, it might have been in the American Bonanza Society's Mag. As with Bobs earlier argument about showing people the bottom end of his o-200 that's perfectly clean on auto oil. There are SO MANY factors, and many of them are how people fly, how they maintain, how they store, how long the aircraft sits, where the aircraft sits, how the engine was built, odd luck that you don't have a faulty/sub par engine part from the get go. Every engine is different, even if they were made side by side with the same parts, they will act differently. SO many variables, I don't think you can attribute them to one thing or another (MMO or Auto Oil for ex) I'm sure you can find someone that's been running normal Aeroshell for 15 years that has just a gorgeous bottom end as Bob's.

As to your balance issue, what I mean is it would be fun to try and solve the problem in other ways (mentioned in an above post) and see if the fault could be corrected in a different way then balancing. Obviously the balance fixed your issue, but part of my argument is that maybe it can be solved in another way that is a bigger picture issue, not just a balance fix. Obviously if your paying someone to do the work you won't be interested because it's much cheaper to just balance it.

Bob, Cars V Airplanes so many differences it's not even worth bringing up. And I agree with Bill, race cars, race engines, high revs, max power, you don't need 15 years of life out them, not exposed to the same climates for long periods of time, etc etc etc comparing race engines to AC engines is not grounds to use as facts. There are different resulting goals that you are trying to accomplish.

hogheadv2
10-31-2011, 03:50 PM
It can't hurt, thats the first concern. You will also get a good inspection of your wheels, axles, all of the suspension.
Maybe try a Hi-Performance Kart shop..... [ the lay flat shifter carts ] Check out the online catalogs for a cheap tool.
Me, I would use a piece of .5" drill rod, turn 2 nylon cones and set it between a V jig much like motorcycle truing/ balancing has been
done for 100+ years.

lardog
12-22-2016, 01:49 PM
I believe I've figured out a way to dynamic balance small aircraft tires. First some background: I have access to a Coats 1050 computerized tire balancer. This machine and many other Coats balancers have a 1 1/8 inch diameter shaft. Many tire shops use them. The front tire on my Cessna 182 has a 1 1/4 inch diameter thru hole. First I removed the bearings and put the wheel/tire on the balancer. I used the smallest cone to hold the tire and wheel against the balancer flange. The cone centered the wheel/tire assembly on the wheel bearing race. Slowly turn the wheel by hand to assure the wheel runs true. It does. Simple so far. Now there are three dimensions that must be input into the computer. The first one is done with a rod that comes out of the machine and touches the rim of the wheel. No problem here. The next one is measured using a large caliper (comes with the machine) that measures the width of the wheel. Input this number, simple so far. The last number is the diameter of the wheel. This is the tricky part. The smallest wheel the machine is rated for is a 10 inch wheel. The Cessna wheel is only 5 inches. What to do? Answer: Enter in 10 inches. From a practical standpoint what does this mean? Answer, not much. How often do you think the tire tech at the tire shop makes mistakes entering in one of the three dimensions? Now spin the wheel and tire and see what the balancer recommends for the weights. Lets say for "example" it calls for 1 1/2 ounces on the outside of the wheel and 1/2 ounce on the inside of the wheel. Add the weights as per the balancer locations. Spin the wheel again. Here is what may happen. This is just an example: On the second spin it may say add 1/4 ounce on the outside of the wheel and zero ounces on the inside. You notice that the 1/4 ounce is 180 degrees from the 1 1/2 ounces you put on previously. The machine is trying to balance the tire but because it has improper inputs it cant do it perfectly on the first try. Instead of adding the 1/4 ounce weight, remove the 1 1/2 ounce weight and replace it with a 1 1/4 ounce weight. Spin it again. Viola, the machine says 0 - 0. The tire and wheel are balanced. You see it doesn't matter that the inputs were incorrect. Zero is zero, the wheel/tire is balanced. You may have to chase it down for and extra spin or two but at the end of the day the wheel/tire is balanced. You could probably input a lot of incorrect numbers and still with a little playing around get it to balance. When the machine reads 0 - 0 the wheel/tire is balanced. The more difficult problem would be convincing the tire tech or tire shop to do it. I hope this helps other members. I believe this is not only superior to a bubble balance or a static balance machine. its also much faster and easier. I balanced my Cessna tires in just a few minutes. Note: I ran a tire shop for 14 years so I have some experience. I often had to figure out how to balance a tire that took weights in a different spot than the balancer specified. It only takes an extra spin or two to track down the balance. Zero is zero.

1600vw
12-22-2016, 05:25 PM
This is something everyone can purchase on any budget. Then go to a tire shop and purchase some wheel weights of the stick on type. They cost very little. You can also modify this to balance props. I have a video showing this.

http://www.harborfreight.com/motorcycle-wheel-balancing-stand-98488.html


https://www.youtube.com/watch?v=LY92vN26EFA

wbecker319
12-23-2016, 08:02 PM
Do as chintonmd said.

1600vw
12-24-2016, 06:30 AM
Do as chintonmd said.

More then one way to do this. But cleaning the bearing then reinstalling then taking it back off and repacking bearings would not be the way I would do it. Take it off and put it back on then take it off then put it back on just seems like more work then one really needs to do. When one could take the wheel off, balance it, and then stick it back on. A lot less work and the way I would do it. But to each his own.

Tony

martymayes
12-24-2016, 06:34 AM
lardog - thanks for your input. That was very informative.

1600vw
12-24-2016, 07:06 AM
lardog - thanks for your input. That was very informative.

I worked with a man at Vail resorts. If you asked this man the time of day he would explain how to make a clock. My point, on something like this, use the KISS method. Not many have access to one of these Computer tire balance machines nor is this needed for the speeds we are talking about on this forum.