theres not any good plane engine breakdown and repair vids...you are a natural!!!you should continue making air repair vids like squirllod for cars and trucks!! really!! you're a natural teacher!!
Thanks for the great videos. Watched these over the winter and replaced the liner and bearings from a broken Supertiger crankcase to good crankcase. Jim
Great share, thank you for putting this together. One thing, it seems you can set the bearings back in by just getting each one started and then use the crankshaft, prop drive, washer and nut to press them in. Just tighten the nut and the two bearings will press into the crankcase. You can, of course, preheat with a torch (I use the little $10 one from Harbor Freight (in the US). It has a more precise heating area for a job like this.). That way the crankshaft counterweight part and the prob drive are parallel as they press the bearings in, keeping the bearings parallel (planar) with each other, and square to the crankcase, as you would want. You don't risk getting either bearing skewed as they press in, avoiding stressing them or even permanent damage.
Guhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhjhhhhhhhhhhhhhhhhhhhhjhhhhjju8uui Ii, œ Nvvvvv
Bruce, Great tutorial, I'm sure that many will dive into the task of replacing bearings,,,, it's not as scary as some fear. As a former, bearing vendor, may I respectfully offer some input. In our industry, most customers who complain about poor bearing life, all too often manage to get contaminants into those brand new, and sometimes very expensive bearings. I'm speaking of industrial sizes, with IDs of 12 inches and more. When I do any engine work/rebuild, I WASH all the fully disassembled parts with dish soap and water and then fully rinse all parts under running water. Not to worry, after every wash and rinse, I immediately spray the part with WD 40 and set it aside on a fresh paper towel for the excess to run off and the water to dry. That's the crank, conrod, piston, sleeve, all pins and snap rings etc. The case is always devarnished and there used to be a product called Sunbeam Metal Clean used to clean off the baked on grease of pots and pans. It melted off the varnish amazingly well and was aluminum friendly. You can't get it anymore but a good substitute is a gasket remover made by Loctite. This melts the gasket and any baked on oil/grease etc. Some brands of chemical paint remover work well too but test them on aluminum first. Then I wash the case and head with soap and water, and set it aside to dry. Often I use a heat gun to hurry things along. I also degum the screws etc. in solvent. All the parts, excluding the case, head and screws are now dropped into a jar of clean, Castor oil. Each part is then laid out on a paper towel to drain and soak up the excess oil. From there, the parts are assembled on a CLEAN workbench covered in several layers of paper towels. I've got in the habit of using SHIELDED bearings. This helps to ensure that no debris gets into the rolling parts as you handle them. In my experience, the shield doesn't prevent oil lube and circulation under normal operation. They cost only a small bit more from any bearing shop. If the bearings are a special size, then original parts are certainly the only option. If you get bearings from a shop, make sure they are brand name, like SKF, or NTN. My take is that if I'm going to replace a bearing, I might as well rebuild the entire engine and this includes new gaskets and often new screws. Too often the Phillips heads get mucked up too easily because OS gives you screws that are TOO SOFT. That was in the old days, OS finally listened to the thousands of complaints and went to Allen head screws.
Can you get sheilded bearings with polimide retainers? The reason I ask is that one of the primary causes of engine destruciton is the failure of the metal retainers which disintegrate and shend shards of metal through the engine. Although shielded bearings may stop the retainer from leaving the bearing, I believe that the sheilds do add to the bearing drag (even if only due to viscous drag created by the oil) and thus for absolute performance, unshielded bearings with polimide retainers are still the desired solution.
***** Metal retainer failure is normally due to very high, bearing rotational speeds. As I recall, the speed ratings involved for bearings in a typical .40 engine are as high as 100,000 RPM,,, speeds not normally imposed on our engines. Poor lubrication, of course, can also be a factor. As can contamination during installation. The shields are attached to the outer race, so they don't rotate and they don't touch the inner race. As well, the oil is diluted with methanol by a factor of 4 or 5 to one so viscosity, wouldn't be that much a factor. I'm going by memory at the moment, but even SEALED bearings, which DO impose a measure of drag on the inner race, and are lubricated with GREASE, still rotate, in our typical .40 engine, within the rated speeds of the bearings in question. A greased bearing doesn't impose much drag to the bearing's moving parts, the grease doesn't churn as one might imagine. Only one half side is greased, with a film of lube feeding the moving parts. Mechanics often think that if some is good, more is better and totally PACK the bearing with grease, In that case, churning is guaranteed with balls skidding instead of rolling and overheated bearings failing prematurely. Many times I've rebuilt engines with the front bearing having a seal on the outside face and the rear bearing with a shield on its inner face. The sealed front bearing keeps external grit out and the shielded, inner bearing keeps out any metal bits or shards that might occur with normal, wear and tear. As in when you find your rod getting sloppy on the crank or wrist pin. OR, (shudder) when your piston pin retainer clips fail. Both the front and rear bearings have oil, (contained in the fuel) feeding the bearings by way of the carburetor. The case, generally, has a slot to help this process along. Often, just the normal, clearances in this area are sufficient. Some sealed bearings come with Teflon seals where the drag of the seal is far, far lower than a rubber seal. These are available in limited sizes, as I recall, usually for the typical, front bearing. But you ARE correct in that polimide retainers are superior to any other, especially at high speeds. This is due to their lighter weight and lower friction under minimal lubrication conditions. However, in industry, we have seen polimide retainers fail too. It may be self serving by the bearing manufacturers but in those cases, they blame poor installation practices, such as installing the bearing into a case using pressure on the inner race. Or vice versa. Or, the dreaded contamination during installation. In our engines, the bearing is retained by a press fit in the case via the outer race and installation is done cold with a special tool that puts pressure on the outer race only. Or, as with your example, the case is heated and the bearing just slides in. That's the way I do it too. In this case, the crank has a slip fit into the inner race and all is good. This isn't ideal, both races SHOULD be firmly attached but the compromise works for us due to the loads being imposed are far below the rated capacity of the bearing. Having said that, I HAVE had cranks spin in the bearing, inner race where when you take out the bearing, the crank is polished mirror smooth at the location of the bearing. This doesn't seem to harm the engine's performance, in my experience. However, I'm speculating that in extreme performance engines that turn up at 40K or more, this isn't something you want to happen. There's a Loctite product sold for cases like this but the perfect solution is special installation tooling that provides for a press fit at the outer AND inner race. The MP Jets .06 was done this way, for some reason, despite being a sport engine. With all due respect, metal retainer failure in our applications can be due to cheap bearings, or bearing contamination during installation. This is why I offered my technique for bearing replacement emphasizing PRISTINE conditions and cleanliness which is what guarantees a good result for your efforts. I have some Norvel engines in .25 and .40 sizes that need rebuilding for which I have the bearings on hand. Let me get the sizes for them and check the specs. Critical family and health issues have kept me from the work bench for the most part, the last half dozen years. I'm in Canada and it's 4 AM, (insomniac) so I really have to get back to bed now, I have commitments that need attention. Will add to the discussion in due course. Thanks for the opportunity to get back in the game. Andy
***** A quick search yielded this. www.globalspec.com/learnmore/mechanical_components/bearings_bushings/bearing_retainers_bearing_cages Phenolic is a good retainer choice as the pores of the fabric soak up oil and can withstand, to a degree, poor lubrication conditions. In industry, many times they were THE solution to a unique bearing failure situaiton.
hopeso To follow up on a strategy to enhance success with Bruce's very good tutorial, about replacing engine bearings, I present the specs for the bearings in the Norvel .40 This is from SKF, a Swedish company, generally regarded as the top bearing outfit in the world. Back end bearing is 61902 and it's rated for 34,000 RPM 61902 ZZ is shielded both sides rated for 28,000 RPM 61902 2RS is sealed both sides, rated at 16,000 RPM A .40 with an 11 X 7 or 12 X 6 prop will turn at 11,000 to 13,000 RPM The open bearing's rating is with oil lubrication The shielded and sealed bearings ratings are with factory applied grease. I've found that after a season of run time, the grease in the shielded bearing is mostly flushed out and it then becomes, basically, oil lubricated as with the factory installed bearing. Even with the fully sealed bearing, for SPORT application, we are well within the factory specs. The front end bearing, which, in my opinion, should always be a sealed bearing has similar specs Unfortunately, SKF doesn't offer this bearing with seals. But here are some specs. 699 open bearing, 48,000 RPM 699 ZZ is good for, 38,000 RPM Good practice on Norvel's part is that their front end, factory bearing, is shielded, at least on one side,,, the one facing the environment. There's no brand name on the Norvel bearings but I'm sure that as with the entire engine, Norvel hasn't cut any corners there. With care, keeping the bearings clean, you can pop in original equipment bearings. Or, pay a little extra and go with shielded bearings on both ends just to be sure.
hopeso The other factor to consider in this application is that the environment inside a methanol/nitromethane powered engine can be quite corrosive. I've been using stainless bearings with great success since, on inspection, most of the bearings I've replaced have suffered from corrosion more than wear. Although stainless bearings are not immune to corrosion, they do corrode far more slowly than regular bearing-steel. The choice of oil also plays a crucial part in reducing corrosion. Many of the popular methanol-soluble synthetics (Coolpower, Klotz) don't have particularly good anti-corrosion packages so a few percent of castor oil helps. More advanced synthetics such as those from Fuchs (Aerosave/Aerosynth) have a brilliant anti-corrossion package which all but eliminated the effects of the low PH environment created by the combustion of nitromethane and the tendency for methanol to absorb water.
Hello mate, great clip and easy to follow. I have a question about castor oils. I noticed a post on the type of oil this motor was run on was a hi-tech ester-based synthetic. Here in NZ the popular brands of synthetic castor are the two brands you say use the low-tech PAG oil (Morgans & Klotz). What are some brands that use the hi-tech oil and what are the advantages over low-tech oils? Cheers :-)
I have align 50 engine on my trex 600 helicopter, and I'm planning to replace rear and front bearing. Do I have to use a gasket on backplate and top head? It seems that your engine have no gasket. Thanks and nice vid!
Aaah, ok, cool. I've got an old 1974 Lark that was found in an attic. After it sitting on my wardrobe for several years, I've recenty decided to have a go at getting it running. I figure the motor will need some looking at...
Awesome video, but how do I know my bearings are bad? Sorry I'm new to RC and have got an old mds 46. I recently got it running after MANY years sitting, and it seems ok.
I wish you'd shown the refitting of the prop driver, as it's apparently heat shrunk on... Will the shaft take just pushing it on after reheating the driver? Can the back of the shaft or the bottom of the crank be damaged?
Thank you for this very informative video. I've recently come into possession of a very abused OS FF-320 and currently have it stripped down to crankcase, crank, and bearings. Do you know if this technique works for the OS multi-cylinder boxer engines as well? I ask because the bearings are a bit rusty and you can feel a slight grind in them as the crank spins, even after liberal amounts of cleaning and lubrication. Besides, I figure if it needs a new cylinder 3 and 4, it can get new bearings.
Hey Bruce just saying i watched your bearing change video it was a great help.my question is i have two os46axvll engines the fist one i had to change the bearings after 6 months the second on thebearing is starting to sound noisy when i turn it over.what type of feul do u use in youre engines as in oil content and nitro content.i had used redback fuel at 5%nitro 15% oil synthetic,now iam runing 5%nitro 15 synthetic 3%caster and i still carnt figure out why my bearings sound like the do any ideas Bruce from Tony in Australia
Thank you for this video. Since that engine is in good shape after that many hours, I assume you use some sort of after run oil. What do you use? WD40? plain engine oil, or after run oil? How do you prep an engine that will be sitting for a few months? Also, could you critique my prop balancing video on my channel?
Clarence Lee recommended ATF as an after-run oil once you have diluted the remaining glow fuel in the engine with WD40 or CRC 5-56. Was in RC Modeler magazine early 90's
Thankyou for that. I have several motors that were given to me,a couple are Enya motors. Where would I find replacement bearings for these Bruce? I do have a manusl for one of the motors. It is a one page deal. I used to warch my brother work on his motors way back in the day. I had forgotten how they disassembled like that but yeah pretty easy compaired to lawn mower motors and snow mobile engines. I always sent the heads in for resleeve because they had to be heated before the new sleeve would go in. then you had to freeze the sleeve to slide it in easily.
Very good video but as a professional engine builder, one thing I would NEVER do is put a scratch in a connecting rod especially across the beam as this will make a stress riser and potentially cause the rod to fail, this simply may not be an issue on rc engines but it's still not generally a good idea.
Bom vídeo.Tava procurando um vídeo que ensinasse a dar manutenção em motores de aeromodelos.Aqui no Brasil a maioria dos aeromodelistas só sabem postar vídeos de motores funcionando, não sei que utilidade tem isso.
You must press the new rear bearing first, and after the new front bearing! Why? Because the front bearing stop the crankshaft (in its running position) when you push it to fit the rear bearing. This mean the rear bearing will not be push full in its housing.If there is not the front bearing, the crankshaft can move a very little more and fit the rear bearing full in its housing! After, when the front bearing is in, there is a very small clearance between crankshaft and rear bearing.I had a shop in the past and worked with lot of engines: I apologize for my bad English, I am from France. Best Regards. Alain G
Open glow plug and drop few drops of multigrade 20w40 engine oil in it when the piston is in bottom dead center and then give it few light hand cracks so the piston and sleeve/liner are lubricated
sounds like lots of pay off for the little work. thanks for the info.. im new to RC.. so much to learn.. i have learn more about electric than gas since my introduction to rc has been building learning to crash quads. but now im wanting to spread my wings. iv built one rubber band balsa kit.. i have 2 more on the shelf i want to convert to RC. i was lost tho because i did not know what dope was until i found some recently and bought it.. so im gonna start on that soon.. lots of fun to be had in this hobby and lots of directions to go from gliders to multirotors to nitro in the end tho i guess one thing is true.. if you are not crashing you are not flying enough :D have a great day. rock on from AZ, US. chris.
To follow up on a strategy to enhance success with Bruce's very good tutorial, about replacing engine bearings, I present the specs for the bearings in the Norvel .40 This is from SKF, a Swedish company, generally regarded as the top bearing outfit in the world. Back end bearing is 61902 and it's rated for 34,000 RPM 61902 ZZ is shielded both sides rated for 28,000 RPM 61902 2RS is sealed both sides, rated at 16,000 RPM A sport .40 with an 11 X 7 or 12 X 6 prop will turn at 11,000 to 13,000 RPM The open bearing's rating is with oil lubrication The shielded and sealed bearings ratings are with factory applied grease. I've found that after a season of run time, the grease in the shielded bearing is mostly flushed out and it then becomes, basically, oil lubricated as with the factory installed bearing. Even with the fully sealed bearing, for SPORT application, we are well within the factory specs. The front end bearing, which, in my opinion, should always be a sealed bearing has similar specs Unfortunately, SKF doesn't offer this bearing with seals. But here are some specs. 699 open bearing, 48,000 RPM 699 ZZ is good for, 38,000 RPM Good practice on Norvel's part is that their front end, factory bearing, is shielded, at least on one side,,, the one facing the environment. There's no brand name on the Norvel bearings but I'm sure that as with the entire engine, Norvel hasn't cut any corners there. With care, keeping the bearings clean, you can pop in original equipment bearings. Or, pay a little extra and go with shielded bearings on both ends just to be sure.
Friend need your help! I got a motor like the one's dismantling, but this engine is stopped long ago ... Following his tips to dismantle the engine, I could do just as you do! When it comes on the heat and make the central axis to change the bearings, I think the engine is stopped the long axis did not move with the beating I gave. I warmed the play and was unable success! What do you advise me to do ?? GRATEFUL
Meu português não é bom, mas vou tentar responder. Acho que seu velho motor é preso com óleo solidificado. Ganhe uma jarra grande e preenchê-lo com um solvente, como acetona ou removedor de tinta. Colocar o motor inteiro e colocar a tampa no frasco. Deixe de molho por duas semanas. Em seguida, retire o motor e deixe-a secar ao sol, ao ar livre, durante 24 horas. Em seguida aquecer o motor com um soprador de ar quente. Agora estou a tentar tirar a manivela e rolamentos conforme mostrado nos vídeos. Limpe todas as peças com água e sabão e spray WD40 para evitar a ferrugem. Aproveite todas as peças em limpo, óleo de rícino. Coloque as peças sobre uma toalha de papel para permitir que o excesso de óleo escorrer. Colocar essas peças em um saco plástico. Levá-lo cabeça e caso e lavagem, novamente, com água e sabão. O caso com um soprador de calor e em seguida toque o caso contra a mesa e o rolamento deve cair. Se não, você precisa aquecer o caso de maior calor. Quando você tomou os rolamentos para fora, limpe o caso novamente, com água e sabão e deixe o processo seco. Boa sorte.
He used the correct bearing for the engine. It is a similar type to a skateboard bearing but it is probably not the same. Small engines use ball bearings, big engines use plain bearings. That is because plain bearings use the oil-wedge effect, which is difficult to achieve in small bearings.
the front bearing ONLY has a seal on the outside. If the front bearing is sealed on both sides the seal of the bearing facing inside MUST be removed before installation.
Thank you for your reply. Another modeler sent me links to rebuild threads on the FT-160 and FF-320, and between your video and his information, I feel like I'll have this thing fixed in no time. You can find the links here: watch?v=XL5C4iwsFtI
theres not any good plane engine breakdown and repair vids...you are a natural!!!you should continue making air repair vids like squirllod for cars and trucks!! really!! you're a natural teacher!!
one of the best videos I have seen...no wait..THE best video I have seen since I started flying
Both of these videos are quite simple!!😁 I'm very pleased that I found them!!🥳
Another very good video. I've been a fan for many years.
Thanks for the great videos. Watched these over the winter and replaced the liner and bearings from a broken Supertiger crankcase to good crankcase.
Jim
jpurcha glad they were of help Jim.
I am about to strip and replace the bearings in a gas engine. I certainly enjoyed viewing this video. Thanks
Worked Perfect. This guy knows his stuff. Many Thanks
Glad to have been of help.
Great videos! Nicely done, very easy to follow and understand. Thanks!
Great share, thank you for putting this together. One thing, it seems you can set the bearings back in by just getting each one started and then use the crankshaft, prop drive, washer and nut to press them in. Just tighten the nut and the two bearings will press into the crankcase. You can, of course, preheat with a torch (I use the little $10 one from Harbor Freight (in the US). It has a more precise heating area for a job like this.). That way the crankshaft counterweight part and the prob drive are parallel as they press the bearings in, keeping the bearings parallel (planar) with each other, and square to the crankcase, as you would want. You don't risk getting either bearing skewed as they press in, avoiding stressing them or even permanent damage.
Guhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhjhhhhhhhhhhhhhhhhhhhhjhhhhjju8uui Ii, œ
Nvvvvv
Thanks, my Irvine 53 lives on thanks to this video.
Excellent clip very interesting & straightforward you are a natural teacher.
Friggin brilliant man - thanks for taking the time to post this!
Great video. I replaced my bearings no problem. First time I had to do this.
Terrific - how tremendously helpful this is! Thank you!
your going to save me almost a 100 bucks on a bearing tool kit! Cheers!
Great video clearly explainable and like tutorial method. Hoping there are more videos coming up in related to our hobies.
very good instructions, but why didn´t you take the chance to give the engine a good clean ?
Nice job!!! I wish I could have seen it running after you finished ....
Great Video, Ive just changed my bearings in a Irvine 52 using your method....it was a doddle!! many thanks :-)
Bruce,
Great tutorial, I'm sure that many will dive into the task of replacing bearings,,,, it's not as scary as some fear.
As a former, bearing vendor, may I respectfully offer some input. In our industry, most customers who complain about poor bearing life, all too often manage to get contaminants into those brand new, and sometimes very expensive bearings. I'm speaking of industrial sizes, with IDs of 12 inches and more.
When I do any engine work/rebuild, I WASH all the fully disassembled parts with dish soap and water and then fully rinse all parts under running water. Not to worry, after every wash and rinse, I immediately spray the part with WD 40 and set it aside on a fresh paper towel for the excess to run off and the water to dry.
That's the crank, conrod, piston, sleeve, all pins and snap rings etc.
The case is always devarnished and there used to be a product called Sunbeam Metal Clean used to clean off the baked on grease of pots and pans. It melted off the varnish amazingly well and was aluminum friendly. You can't get it anymore but a good substitute is a gasket remover made by Loctite. This melts the gasket and any baked on oil/grease etc. Some brands of chemical paint remover work well too but test them on aluminum first.
Then I wash the case and head with soap and water, and set it aside to dry. Often I use a heat gun to hurry things along. I also degum the screws etc. in solvent.
All the parts, excluding the case, head and screws are now dropped into a jar of clean, Castor oil. Each part is then laid out on a paper towel to drain and soak up the excess oil. From there, the parts are assembled on a CLEAN workbench covered in several layers of paper towels.
I've got in the habit of using SHIELDED bearings. This helps to ensure that no debris gets into the rolling parts as you handle them. In my experience, the shield doesn't prevent oil lube and circulation under normal operation. They cost only a small bit more from any bearing shop. If the bearings are a special size, then original parts are certainly the only option.
If you get bearings from a shop, make sure they are brand name, like SKF, or NTN.
My take is that if I'm going to replace a bearing, I might as well rebuild the entire engine and this includes new gaskets and often new screws. Too often the Phillips heads get mucked up too easily because OS gives you screws that are TOO SOFT. That was in the old days, OS finally listened to the thousands of complaints and went to Allen head screws.
Can you get sheilded bearings with polimide retainers? The reason I ask is that one of the primary causes of engine destruciton is the failure of the metal retainers which disintegrate and shend shards of metal through the engine. Although shielded bearings may stop the retainer from leaving the bearing, I believe that the sheilds do add to the bearing drag (even if only due to viscous drag created by the oil) and thus for absolute performance, unshielded bearings with polimide retainers are still the desired solution.
*****
Metal retainer failure is normally due to very high, bearing rotational speeds. As I recall, the speed ratings involved for bearings in a typical .40 engine are as high as 100,000 RPM,,, speeds not normally imposed on our engines. Poor lubrication, of course, can also be a factor. As can contamination during installation.
The shields are attached to the outer race, so they don't rotate and they don't touch the inner race. As well, the oil is diluted with methanol by a factor of 4 or 5 to one so viscosity, wouldn't be that much a factor.
I'm going by memory at the moment, but even SEALED bearings, which DO impose a measure of drag on the inner race, and are lubricated with GREASE, still rotate, in our typical .40 engine, within the rated speeds of the bearings in question.
A greased bearing doesn't impose much drag to the bearing's moving parts, the grease doesn't churn as one might imagine. Only one half side is greased, with a film of lube feeding the moving parts. Mechanics often think that if some is good, more is better and totally PACK the bearing with grease, In that case, churning is guaranteed with balls skidding instead of rolling and overheated bearings failing prematurely.
Many times I've rebuilt engines with the front bearing having a seal on the outside face and the rear bearing with a shield on its inner face. The sealed front bearing keeps external grit out and the shielded, inner bearing keeps out any metal bits or shards that might occur with normal, wear and tear. As in when you find your rod getting sloppy on the crank or wrist pin. OR, (shudder) when your piston pin retainer clips fail.
Both the front and rear bearings have oil, (contained in the fuel) feeding the bearings by way of the carburetor. The case, generally, has a slot to help this process along. Often, just the normal, clearances in this area are sufficient.
Some sealed bearings come with Teflon seals where the drag of the seal is far, far lower than a rubber seal. These are available in limited sizes, as I recall, usually for the typical, front bearing.
But you ARE correct in that polimide retainers are superior to any other, especially at high speeds. This is due to their lighter weight and lower friction under minimal lubrication conditions. However, in industry, we have seen polimide retainers fail too. It may be self serving by the bearing manufacturers but in those cases, they blame poor installation practices, such as installing the bearing into a case using pressure on the inner race. Or vice versa. Or, the dreaded contamination during installation.
In our engines, the bearing is retained by a press fit in the case via the outer race and installation is done cold with a special tool that puts pressure on the outer race only. Or, as with your example, the case is heated and the bearing just slides in. That's the way I do it too. In this case, the crank has a slip fit into the inner race and all is good. This isn't ideal, both races SHOULD be firmly attached but the compromise works for us due to the loads being imposed are far below the rated capacity of the bearing.
Having said that, I HAVE had cranks spin in the bearing, inner race where when you take out the bearing, the crank is polished mirror smooth at the location of the bearing. This doesn't seem to harm the engine's performance, in my experience.
However, I'm speculating that in extreme performance engines that turn up at 40K or more, this isn't something you want to happen. There's a Loctite product sold for cases like this but the perfect solution is special installation tooling that provides for a press fit at the outer AND inner race. The MP Jets .06 was done this way, for some reason, despite being a sport engine.
With all due respect, metal retainer failure in our applications can be due to cheap bearings, or bearing contamination during installation.
This is why I offered my technique for bearing replacement emphasizing PRISTINE conditions and cleanliness which is what guarantees a good result for your efforts.
I have some Norvel engines in .25 and .40 sizes that need rebuilding for which I have the bearings on hand. Let me get the sizes for them and check the specs.
Critical family and health issues have kept me from the work bench for the most part, the last half dozen years.
I'm in Canada and it's 4 AM, (insomniac) so I really have to get back to bed now, I have commitments that need attention.
Will add to the discussion in due course. Thanks for the opportunity to get back in the game.
Andy
*****
A quick search yielded this. www.globalspec.com/learnmore/mechanical_components/bearings_bushings/bearing_retainers_bearing_cages
Phenolic is a good retainer choice as the pores of the fabric soak up oil and can withstand, to a degree, poor lubrication conditions. In industry, many times they were THE solution to a unique bearing failure situaiton.
hopeso To follow up on a strategy to enhance success with Bruce's very good tutorial, about replacing engine bearings, I present the specs for the bearings in the Norvel .40
This is from SKF, a Swedish company, generally regarded as the top bearing outfit in the world.
Back end bearing is 61902 and it's rated for 34,000 RPM
61902 ZZ is shielded both sides rated for 28,000 RPM
61902 2RS is sealed both sides, rated at 16,000 RPM
A .40 with an 11 X 7 or 12 X 6 prop will turn at 11,000 to 13,000 RPM
The open bearing's rating is with oil lubrication
The shielded and sealed bearings ratings are with factory applied grease.
I've found that after a season of run time, the grease in the shielded bearing is mostly flushed out and it then becomes, basically, oil lubricated as with the factory installed bearing.
Even with the fully sealed bearing, for SPORT application, we are well within the factory specs.
The front end bearing, which, in my opinion, should always be a sealed bearing has similar specs
Unfortunately, SKF doesn't offer this bearing with seals. But here are some specs.
699 open bearing, 48,000 RPM
699 ZZ is good for, 38,000 RPM
Good practice on Norvel's part is that their front end, factory bearing, is shielded, at least on one side,,, the one facing the environment. There's no brand name on the Norvel bearings but I'm sure that as with the entire engine, Norvel hasn't cut any corners there.
With care, keeping the bearings clean, you can pop in original equipment bearings. Or, pay a little extra and go with shielded bearings on both ends just to be sure.
hopeso
The other factor to consider in this application is that the environment inside a methanol/nitromethane powered engine can be quite corrosive. I've been using stainless bearings with great success since, on inspection, most of the bearings I've replaced have suffered from corrosion more than wear. Although stainless bearings are not immune to corrosion, they do corrode far more slowly than regular bearing-steel.
The choice of oil also plays a crucial part in reducing corrosion. Many of the popular methanol-soluble synthetics (Coolpower, Klotz) don't have particularly good anti-corrosion packages so a few percent of castor oil helps. More advanced synthetics such as those from Fuchs (Aerosave/Aerosynth) have a brilliant anti-corrossion package which all but eliminated the effects of the low PH environment created by the combustion of nitromethane and the tendency for methanol to absorb water.
fantastic thank you for taking the time to make these vids. very helpful
I understand your hurry !
The video on cleaning will be anxiously expected.
Thanks
very helpful, thanks for posting.
very, very nice and professional guide.
Hello mate, great clip and easy to follow. I have a question about castor oils. I noticed a post on the type of oil this motor was run on was a hi-tech ester-based synthetic. Here in NZ the popular brands of synthetic castor are the two brands you say use the low-tech PAG oil (Morgans & Klotz). What are some brands that use the hi-tech oil and what are the advantages over low-tech oils? Cheers :-)
completely agree. this guy is great
I have align 50 engine on my trex 600 helicopter, and I'm planning to replace rear and front bearing. Do I have to use a gasket on backplate and top head? It seems that your engine have no gasket. Thanks and nice vid!
Great video's . Thank you
Excellent stuff 🙂👌🏻👍🏻
Aaah, ok, cool.
I've got an old 1974 Lark that was found in an attic. After it sitting on my wardrobe for several years, I've recenty decided to have a go at getting it running. I figure the motor will need some looking at...
Awesome video, but how do I know my bearings are bad? Sorry I'm new to RC and have got an old mds 46. I recently got it running after MANY years sitting, and it seems ok.
Very helpul! Cheers mate!
I wish you'd shown the refitting of the prop driver, as it's apparently heat shrunk on...
Will the shaft take just pushing it on after reheating the driver? Can the back of the shaft or the bottom of the crank be damaged?
Thank you for this very informative video. I've recently come into possession of a very abused OS FF-320 and currently have it stripped down to crankcase, crank, and bearings. Do you know if this technique works for the OS multi-cylinder boxer engines as well? I ask because the bearings are a bit rusty and you can feel a slight grind in them as the crank spins, even after liberal amounts of cleaning and lubrication. Besides, I figure if it needs a new cylinder 3 and 4, it can get new bearings.
Thank you very much,god bless you and your familly
great video, very clear and precise.
@xjet agreed. although i usually used a spot from a grease pen or a marker. no ill effects from it either
Very Good Video , I have in my OS55 stainless steel bearings
And i fly with Rapicon 30%
Hey Bruce just saying i watched your bearing change video it was a great help.my question is i have two os46axvll engines the fist one i had to change the bearings after 6 months the second on thebearing is starting to sound noisy when i turn it over.what type of feul do u use in youre engines as in oil content and nitro content.i had used redback fuel at 5%nitro 15% oil synthetic,now iam runing 5%nitro 15 synthetic 3%caster and i still carnt figure out why my bearings sound like the do any ideas Bruce from Tony in Australia
what type of torque tools do you use ?
Thank you for this video.
Since that engine is in good shape after that many hours, I assume you use some sort of after run oil. What do you use? WD40? plain engine oil, or after run oil?
How do you prep an engine that will be sitting for a few months?
Also, could you critique my prop balancing video on my channel?
Clarence Lee recommended ATF as an after-run oil once you have diluted the remaining glow fuel in the engine with WD40 or CRC 5-56. Was in RC Modeler magazine early 90's
How long did it take to get that many hours? Years and years? Great video. Thanks
gracias fue muy instructivo para mi gracias gracias gracias . mi nombre es octavio desde argentina
Thankyou for that. I have several motors that were given to me,a couple are Enya motors. Where would I find replacement bearings for these Bruce? I do have a manusl for one of the motors. It is a one page deal. I used to warch my brother work on his motors way back in the day. I had forgotten how they disassembled like that but yeah pretty easy compaired to lawn mower motors and snow mobile engines. I always sent the heads in for resleeve because they had to be heated before the new sleeve would go in. then you had to freeze the sleeve to slide it in easily.
Try RC Bearings at www.rcbearings.com/ they have always given me excellent service.
superb exactly what I needed
I Love my Thunder Tiger pro 46,best engine I've ever used.
you should note,never use 3in1 oil,it'll burn out glow plugs!!
I've thunder tiger pro 50, kindly suggest me best fuel for it
Very good video but as a professional engine builder, one thing I would NEVER do is put a scratch in a connecting rod especially across the beam as this will make a stress riser and potentially cause the rod to fail, this simply may not be an issue on rc engines but it's still not generally a good idea.
Great video thanks was a great help
very good tutorial....
Does the conrod also have some form of bearing where it connects to the crankshaft and piston? Or just bare metal on metal?
It's a simple metal bush on lower side of conrod
top man ,excellent video thanks
Bom vídeo.Tava procurando um vídeo que ensinasse a dar manutenção em motores de aeromodelos.Aqui no Brasil a maioria dos aeromodelistas só sabem postar vídeos de motores funcionando, não sei que utilidade tem isso.
very nice video, but my engine is trx 3.3 and idk how to check the crankshaft??
Great vid. Thanks.
You must press the new rear bearing first, and after the new front bearing! Why? Because the front bearing stop the crankshaft (in its running position) when you push it to fit the rear bearing. This mean the rear bearing will not be push full in its housing.If there is not the front bearing, the crankshaft can move a very little more and fit the rear bearing full in its housing! After, when the front bearing is in, there is a very small clearance between crankshaft and rear bearing.I had a shop in the past and worked
with lot of engines: I apologize for my bad English, I am from France. Best Regards. Alain G
i ran a new engine for one season emptied the fuel out of it but it seems to turn harder. should i oil it, and with what kind of oil
Open glow plug and drop few drops of multigrade 20w40 engine oil in it when the piston is in bottom dead center and then give it few light hand cracks so the piston and sleeve/liner are lubricated
hey bruce how many hours did you get on the partial rebuild?
Usually good for a couple of years at two or three flights a weekend -- whatever that adds up to.
sounds like lots of pay off for the little work. thanks for the info.. im new to RC.. so much to learn.. i have learn more about electric than gas since my introduction to rc has been building learning to crash quads. but now im wanting to spread my wings. iv built one rubber band balsa kit.. i have 2 more on the shelf i want to convert to RC. i was lost tho because i did not know what dope was until i found some recently and bought it.. so im gonna start on that soon.. lots of fun to be had in this hobby and lots of directions to go from gliders to multirotors to nitro in the end tho i guess one thing is true.. if you are not crashing you are not flying enough :D have a great day. rock on from AZ, US.
chris.
Hell I found this entertaining even though I never intend to fly gas models..
To follow up on a strategy to enhance success with Bruce's very good tutorial, about replacing engine bearings, I present the specs for the bearings in the Norvel .40
This is from SKF, a Swedish company, generally regarded as the top bearing outfit in the world.
Back end bearing is 61902 and it's rated for 34,000 RPM
61902 ZZ is shielded both sides rated for 28,000 RPM
61902 2RS is sealed both sides, rated at 16,000 RPM
A sport .40 with an 11 X 7 or 12 X 6 prop will turn at 11,000 to 13,000 RPM
The open bearing's rating is with oil lubrication
The shielded and sealed bearings ratings are with factory applied grease.
I've found that after a season of run time, the grease in the shielded bearing is mostly flushed out and it then becomes, basically, oil lubricated as with the factory installed bearing.
Even with the fully sealed bearing, for SPORT application, we are well within the factory specs.
The front end bearing, which, in my opinion, should always be a sealed bearing has similar specs
Unfortunately, SKF doesn't offer this bearing with seals. But here are some specs.
699 open bearing, 48,000 RPM
699 ZZ is good for, 38,000 RPM
Good practice on Norvel's part is that their front end, factory bearing, is shielded, at least on one side,,, the one facing the environment. There's no brand name on the Norvel bearings but I'm sure that as with the entire engine, Norvel hasn't cut any corners there.
With care, keeping the bearings clean, you can pop in original equipment bearings. Or, pay a little extra and go with shielded bearings on both ends just to be sure.
Friend need your help!
I got a motor like the one's dismantling, but this engine is stopped long ago ...
Following his tips to dismantle the engine, I could do just as you do! When it comes on the heat and make the central axis to change the bearings, I think the engine is stopped the long axis did not move with the beating I gave.
I warmed the play and was unable success!
What do you advise me to do ??
GRATEFUL
Meu português não é bom, mas vou tentar responder. Acho que seu velho motor é preso com óleo solidificado.
Ganhe uma jarra grande e preenchê-lo com um solvente, como acetona ou removedor de tinta. Colocar o motor inteiro e colocar a tampa no frasco. Deixe de molho por duas semanas.
Em seguida, retire o motor e deixe-a secar ao sol, ao ar livre, durante 24 horas.
Em seguida aquecer o motor com um soprador de ar quente. Agora estou a tentar tirar a manivela e rolamentos conforme mostrado nos vídeos.
Limpe todas as peças com água e sabão e spray WD40 para evitar a ferrugem. Aproveite todas as peças em limpo, óleo de rícino. Coloque as peças sobre uma toalha de papel para permitir que o excesso de óleo escorrer. Colocar essas peças em um saco plástico.
Levá-lo cabeça e caso e lavagem, novamente, com água e sabão. O caso com um soprador de calor e em seguida toque o caso contra a mesa e o rolamento deve cair. Se não, você precisa aquecer o caso de maior calor.
Quando você tomou os rolamentos para fora, limpe o caso novamente, com água e sabão e deixe o processo seco.
Boa sorte.
really vv thankyou...........
Great Post! Thanks.
i have to replace the casting can i use the old good used bearings?
He used the correct bearing for the engine. It is a similar type to a skateboard bearing but it is probably not the same.
Small engines use ball bearings, big engines use plain bearings. That is because plain bearings use the oil-wedge effect, which is difficult to achieve in small bearings.
Nice and clear video! Btw, its an Engine, not a Motor :) Thank you for a great video!
Where can I buy an engine like this on the Internet?
Doesn't it use green sealer on the od of the bearing?
Is it the same to engine évoulution 10cc gazoline ?
Brilliant!!
Thank you!
Were did u get the motor
Its taiwan made, one of the best nitro motor, it's pro 46 nd pro 50 is excellent
GREAT
do yo have to hone the motor
It looks like you've used a skateboard bearing, yes?
the front bearing ONLY has a seal on the outside. If the front bearing is sealed on both sides the seal of the bearing facing inside MUST be removed before installation.
That sound reasonable and logic. Did buy a tt. 46 pro today. I will remember this advice. Regards
what oil is that
Any multigrade 20w40
en donde compro ese motor
no se si encuentres ese motor, pero seguramente encuentres buenos motores a un buen precio en hobbyking.com
It seems to me, that you use fuel with high content of castor oil.. The piston is black and some spots on the surface of the engine.
انت رائع
Nice video. I recognise all the scars on your left hand ..... share the pain!
what waght of mobil one
7,5 ccm ?????
I'm surprised that you don't clean up the parts with petrol. Just a wipe with a dry towel.
4:38 ooh yeah...
For first lubrication car oil is 100% fine
You have not clean the body of the engine. It looks really bad.
Thank you for your reply. Another modeler sent me links to rebuild threads on the FT-160 and FF-320, and between your video and his information, I feel like I'll have this thing fixed in no time. You can find the links here: watch?v=XL5C4iwsFtI
Desculpe o meu inglês!
I don't speek ingels
Os reasembly
Hairy Arms.
You must have fingers like leather
goood video look on my chanel my tarxxas T-Maxx
new motor
smart... heat it up with a torch on wood... hmmmmmmmm