Engine Bearings???
 

I have been looking at getting a set of bearings for my O.S. 81 VR-M and,WOW, what a variety of prices. BOCA comes in highest and at the other end is RCBearings.com. I have learned in the past that you usually get what you pay for but have to ask, Has any-one had experience with rcbearings.com. I am looking at getting the ceramic bearings because of the marine app and have heard they are the way to go. Any input??

RE: Engine Bearings???
 

Ceramics are good in NON-impact applications. I don't like them for anything that might get a prop-strike.
Marine and ducted fan engines are OK. I've used both Boca and RC-Bearings and have been happy with both suppliers.

RE: Engine Bearings???
 

I have never used ceramic befor but like I said I have been told that for marine it was worth it. Boca wants $77 for the set and RCBearings is $25! I think I might try a set.

RE: Engine Bearings???
 

I have had nothing but bad luck with ceramics in aero and ducted fan engines. They are fast...for a while. Contact RC Bearings and get stainless if they come with non metallic retainers. If not, get steel bearings with non metallic retainers. In either case, remove the glow plug,cover the hole with a rag and spin the engine with starter while squirting ATF in the carb to flush out the nitro. Yes it's messy, but the bearings last a long long time. On planes I run them a few moments on FAI fuel, not as messy.

RE: Engine Bearings???
 

Put a new set of steel bearings in my MVVS 49 ... $12.00 for both. Bought off an *bay vendor. Work real well. Very smooth. If I only get a couple of seaons flying I won't mind. I use 50:50 castor/synth lube and corrosion is not an issue.

RE: Engine Bearings???
 

G'day

I rarely have to replace bearings but the few I have replaced in the last few years have come from RC-Bearings. I did try some ceramics in a Saito 65 but they did not like the engine being rammed into the ground. Now I just use steel bearings with flexible cages.

I use fuel with 5% castor and 15% synthetic and don't seem to have a serious problem with rust. Dirt ingress from sudden and unexpected contact with our rather sandy soil is a far more serious problem.

Mike in Oz

RE: Engine Bearings???
 

A ball from a ceramic comes apart and it will destroy the innards of your motor on its way out.

I've been buying from RC Bearings for years and heli engines need bearings far more than most other applications (save for maybe cars)

RE: Engine Bearings???
 

Yup - against medical advice I installed a set of ceramics in my Saito. Didn't take long for a ball to escape and get stuck between the crank throw and the side of the really soft aluminum crank case. One guess as to which bit won.

Stainless from rc-bearings work well - OS, Evo, Saito, YS, ...

RE: Engine Bearings???
 

I replaced the stock metal retainer bearings in my TT 46 pro with stainless bearings from RCBearings and have no complaints. I believe most engine bearings if not all from RCBearings use phenolic retainers. No issues yet in my low-time 46.

RE: Engine Bearings???
 

Just go down to the your local bearing store. Take your old bearings and let them get the numbers. Bearings are bearings. Model engine bearings in most cases are off the shelf bearings not special made.

RE: Engine Bearings???
 

That's a very good suggestion, husker.

RE: Engine Bearings???
 

Your local store, if they have them in stock will be about 2-4 times the price of RCBearings. I tried to buy them local one time and the bearing was not only 4 times more expesive, but I had to pay for 8.00 for shipping on top of it because they did not have it in stock.

RE: Engine Bearings???
 

Well I just had to see and for 20 bucks I can't resist. I talked to the rep at RCBearing and for my application I decided to go on and try a set of the ceramics. I appreciate the input and will let you know how they work out for me.

RE: Engine Bearings???
 

I bought a set of bearings for a 46 FX here in town and I think they were around $20 for the set. W8YE ended up with the engine.

RE: Engine Bearings???
 

I think you will be happy with what you get from RC Bearings. I have been happy with my purchases from them. As already stated, the bearings we use are pretty standard items. I think price and availability are the most important factors when buying.

RE: Engine Bearings???
 

I have two Saito FA-91 engines that need bearings. I can get both sets from RCBearings for $20 shipped. Getting one set locally will cost me more Han that.

RE: Engine Bearings???
 

Sometimes, you may want to price the factory bearings. I got a pair of bearings for a Evolution .455 from Advantage Hobby for about $15 total. These were the Evolution packaged bearings. Anyway, you sometimes save time/money by using other sources. Other times, not.

RE: Engine Bearings???
 

Try that with OS :D

RE: Engine Bearings???
 

Go with Stainless Bearings from RC Bearings. No rust , no issues, no problems.

RE: Engine Bearings???
 

The first few 46NT engines I bought had bearings that had polymite (plastic) retainers as did the bearings sets on the hook at the LHS. Those inexpensive bearings really held up and they fit most 46/55 engines, a fact of which I took advantage of. That all changed a few years ago in both engines and whats in the packages as they are now steel cages and don't hold up any better or worse than what can be found in any other make engine.

RE: Engine Bearings???
 

I wouldn't bet anything on the rust claim for any brand.

FF- the bearings I changed were on the original production 46NT. I have 3 46NTs in my shop that are only 2 years old. I need to look at those.

RE: Engine Bearings???
 

I wouldn't bet anything either, but they seem to last longer.

The the stainless bearings for our planes is an alloy called 440 C. Unlike most other stainless, it is magnetic, hardenable and is less corrosion RESISTANT. 300 series stainless has a much higher resistance, but cant be hard enough, at least for our needs. There are also the "PH" types (Precipitation Hardening) stainless's that can be hardened, but it's not as common in our bearings sizes and can't be made as hard as the 440c type.

Finally, I had a stainless bearing get rough and I'll have a look see at it this weekend.

RE: Engine Bearings???
 

I would be careful using ceramic bearings in marine engines if you are running a surface drive. Surface drives load and unload the prop which in turn becomes a vibration/ impact type load on the main bearings. They might be just fine, just some food for thought!!! I do know that ceramic bearings dont do so well under impact type conditions.

RE: Engine Bearings???
 

Can't say all of this is very encouraging being as I jumped at the opportunity to try the ceramics. Couldn't resist at the price of them. On the other hand experience is king and I do have another engine for parts. Really hope theywork out though, I was kinda planning on re-building that spare engine. Just to show you what I was dealing with when I decided to try the ceramics I will show you what I found when I pulled mine down. This engine came from a friend of mine and I do not know the history of it but it did run(believe it or not it ran pretty good) Maybe you can tell me what this mess came from. Retainer in the rear bearing was gone and both were rough.

RE: Engine Bearings???
 

Eeeeeuuuuwwww Yuuuuuck! Rode hard and put away wet?

RE: Engine Bearings???
 

Thats what I was thinking. And the worst part is Boat fuel is 30%+ nitro. Oooofda.

RE: Engine Bearings???
 

Unless you are prepared to sacrifice an engine on the alter of curiosity It would be safer to try the stainless option. When ceramics fail they do it suddenly and frequently cause catastrophic engine damage.

Steel bearings, including stainless, will give plenty of warning if you check regularly for roughness of the crankshaft.

The biggest killer of glow engine bearings is poor storage, allowing rust to do the damage.

RE: Engine Bearings???
 

All that rust is what is left of the bearing retainer!! That is a prime example of what happens when you dont flush your mill out after the last run of the day or even worse if the motor inhales a dose of water, which looks to be the cause here...

RE: Engine Bearings???
 

I figured it was from the bearing. It was the only thing in the engine that was bad. Cyl showed some wear but compression was decent. It will be replaced any-way along with the piston and rod. So, other than after run oil, what would be the end-of-the-day procedure to follow. I know it had a few "dunks" and may have ingested water but I would pull the plug and run some fuel thru it. Followed up by a dry run, you know a slow mid-range run down the river where it is less likely to suck any more water. I always pull the pipe and make sure it is clean and dry. I would like to figure out how to get the intake to where it isn't so low and apt to get water but haven't figured that yet. This thing had set for quite a while befor I got it. I probably put three or four good run days on it befor I pulled it down and found that mess. As good as this boat runs I don't mind at all to take the time to maintain it like I should and would if I just knew what it was that I was not doing. I don't run the high nitro fuel by the way. So far I have only ran 15%nitro and 18% oil in it. I did get some 60% and some 40% from the friend that gave me the boat but I haven't seen the need for it. This thing will move out with the 15% and I don't race. There isn't any-one here to race with. Just me and my son takeing turns and grinning at each other.

RE: Engine Bearings???
 

No ideas on how to keep this from happening again??

RE: Engine Bearings???
 

Make sure you run the engine dry of fuel - pull the line off the carb, start it and give it throttle. Follow up with after run oil. Be careful, though, some of them are not kind to o-rings and seals in your carb.

RE: Engine Bearings???
 

Air tool oil or transmission fluid are good after run oil. The methanol left over in the crankcase is the source of corrosion as methanol is hygroscopic and will absorb moisture from the atmosphere and will cause bearing corrosion. Start and run the engine wide open throttle with the fuel line disconnected at the carburetor to remove as much as possible the methanol left over in the crankcase. After running the engine with the fuel line to the carburetor disconnected, leave the fuel line disconnected and then you squirt after run oil into the carburetor and spin with the starter for about 3 seconds, then squirt again into the carburetor and spin the starter doing it 3 times more the squirting and spinning to circulate well the after run oil into the front and rear bearings. That should coat the bearings with enough after run oil. Corrosion from methanol left over in the crankcase is a big killer of bearings. Leave the fuel line disconnected at the carburetor and plug the fuel line with a fuel dot or something handy and plug the carburetor nipple as well to prevent dirt getting into your carburetor, as you don't want any siphoning of the fuel from the fuel tank to the carburetor and down into the crankcase again. 'Nuff said. Larry.

RE: Engine Bearings???
 

Use castor oil, at least 30% castor to the synthetic oil. Run the engine dry at the end of the day and make sure the exhaust port is open. If you must use an afterrun oil wait an hour or so to allow any fuel to dry out., Most after run oils will not mix with the fuel and all will not mix with water. If wet fuel or water is in the engine the oil will trap the fuel or water against the metal parts.

RE: Engine Bearings???
 

Yes, the fuel these engines burn is the worst thing you could leave sitting inside a engine, Hydroscopic means that it absorbs water out of the air and the methanol in glow fuel is very hydroscopic.  Castor oil will do nothing to displace the water and tends to gum up if it sits too long.  I agree with the airtool oil or trans fluid.  Transmission fluid is one of the best oils we have.  What I do at the end of the day is run the engine out of fuel at idle, then give it a good squirt of WD40-  the "WD" stands for water displacing which is a good thing, then run a few drops of air tool oil or trans fluid through it and you should be good to go.

RE: Engine Bearings???
 

No, castor doesn't displace water, but it protects the metal surfaces from rust.

If you read about bearings for a while on RCU, you will find that the rust problem is illogical at times. Members have rust issues often when they do everything right to prevent it. Then, people like me don't do a thing and never get rust.

RE: Engine Bearings???
 

My take on these bearings is in my review.

http://www.rcbearings.com/16001c-12x28x7-ceramic/

I looked at Boca and RC-Bearings. Boca was $40 for the same bearing that RC sold for $11 but it had a plastic retainer. A YS has 4 bearings but I only needed the rear bearing. Both Boca and RC had sets of chrome steel. On the web sites Boca on the single bearing reported back order until you got to ceramic and RC did not list anything other than ceramic.
I wil certainly still buy from RC Bearings but by phone and not on the web site. That way I can ask for chrome steel balls and bearings with non metallic retainers.

Denis

RE: Engine Bearings???
 

The trash in that motor isn't rust or at least I don't think it is. I do believe it is part of the retainer from the bearing and maybe some sludge from water the motor had ingested that I didn't get out. It was put away and sat dormant for about a month then it wouldn't run. I installed the new bearings and did use the ceramics and put another cyl-piston in it. I will attempt to make sure the water gets completely out befor I store her again. I am not used to getting water out of my engines because this is my first run at boats. I usually fly and have probably 35-40 that never get after-run or ran dry. I usually de-fuel the tank and wipe em down and hang them back on the ceiling. Never had any problems with them and I got some pretty old engines on them. I guess boats require more maintenance. I would turn it up-ide down and run it to get the mess out of the crank-case but this engine really scares the mess out of me when it is ran out of the water. Turns up pretty hard and quick. How-ever, it is pretty simple to get the carb and back-plate off after a days run to see what is there.

RE: Engine Bearings???
 

I would not recommend this at all. Bearings have a rating system called the ABEC system. Basically a bearing with a higher number (IE 9 ) has much closer tolerances than a bearing with a rating of 1. Which bearing would you rather run in your engine??If you put a lower rated bearing in your engine there is a good chance you will damage the crankshaft to block sealing effect that is super important in our small engines,Also the bearing retainer is pretty important in some engines, for example a steel cage would be fine in an airplane engine that only turns 16k but that same steel cage(retainer) in a car or boatengine could be trouble. Most high quality carand marine bearings will use a nylon or phenolic type retainer because they can turn in excess of 30,000 rpm's. Stainless bearings are not always the better option either as stainless steel is softer than achrome plated bearing, that being said if you stay with qualitystainless bearings you should be fine.

RE: Engine Bearings???
 

Castor is probally one of the best oils when it comes to protecting a running engine, however it does not make a good oil for protecting a stored engine, it will end up turning into gum and creating a mess . ATF will actually stay fluid and prevent any moisture from attacking the inside of our engines. Not too mention atf is much cheaper to buy as well.

RE: Engine Bearings???
 

Thats true of the ABEC ratings to a point but there's no reason for our application to get out of hand.