armody

My Feedback: (10)

Hi there all

Just thinking for many days to ask about ABC and Ringed engines. I read on a website that ABC engines are more powerful and good than Ringed engines. This is what it says

Model airplane engines many times come in ringed and ABC versions. The ringed engine has a piston ring to create the piston-cylinder seal that is needed for compression. An ABC engine has no ring. The ABC stands for Aluminum, Brass, Chrome. It means the engine has an aluminum piston that is running inside of a Brass cylinder that is chrome plated. The ABC engine has the potential for more power and requires very little break-in. It is, however, less tolerant of dirt or dust that may be ingested by the engine.

I'd like to know that ABC or Ringed engines are both in 2 stroke and 4 stroke, second which engines are to be bought ABC or Ringed and which are more long lasting rubust and sturdy?

Second Question, Engines with bearings are more reliable and long lasting than engines with bushings?

Thanks for your input

Mody

DMcQuinn

My Feedback: (13)

Both ringed and non-ringed glow engines will last for a very long time if run at the proper fuel mixture (not too lean). I have had an OS .46 glow engine (no ring) for over 10 years and hundreds of flights. After about 10 years I had to replace the bearings. But not the piston or cylinder liner. Hosnestly I would not use the "ringed vs ABC" property as a buying decision.

The use of bearings vs bushings is much more important. Bearing engines typically put out more power and last longer.

Another important factor is the carburetor. I avoid "air-bleed" carbs and insted buy dual-needle-vale carbs.

Typically the lower cost glow engines are characterized by these factors: Bushings and air-bleed carbs.
Higher quality engines are characterized by: Ball Bearings and two-needle carbs.

ABC and ringed pistons can be found in both high-end and low-end motors. OS tends to make a lot of ABC (or ABN) motors. Supertigre likes to make ringed engines, etc.

armody

My Feedback: (10)

Thanks a lot for your reply DMcQuinn,

Well, it is learned that ABC engines are good than Ringed, and Bearings ones are better than Bushings one. If Carburetor bleeds as it does to my friend's .46 O.S. engine ultimately it gives a dead stick but it flies, I dont like carb bleeding. Well, Thanks once again.

Mody

bruce88123

I use both ringed and non-ringed engines equally but I will NOT buy an engine without bearings or a good carburetor. Pay the little bit more as it's worth the extra cost. Ringed engines ARE easier to damage with a lean run though.

armody

My Feedback: (10)

Thanks for the reply bruce

What about 4 stroke engines, do 4 stroke engines are ABC or Ringed? and do they have bearings and bushings?

Mody

bigedmustafa

My Feedback: (2)

4-stroke engines can be ringed or non-ringed like two strokes, they can also have dual needle or air bled carburators. I don't know of any 4-strokes currently being sold that have bushings instead of ball-bearings. Most of the popular 4-strokes sold today are ringed and have dual needle carburators.

Bushing engines aren't inherently weaker or shorter lasting than their ball-bearing counterparts. The O.S. .65 LA is much lighter weight than the O.S. .61 FX, but will actually turn some props faster than the .61 FX using the same fuel and glow plug. Thunder Tiger's published specifications show that their GP-61 produces more horsepower than their Pro .61 ball-bearing engine.

Bushing engines get a bad rap for two reasons:

1) The O.S. .40 LA is by far the most commonly sold bushing engine in existence, and it is weak compared to all other .40-sized 2-strokes. The Thunder Tiger GP-42, for example, is a bushing engine with an air bleed carburator just like the O.S. .40 LA, but is signficantly more powerful. Too many modellers think that the .40 LA is representative of the power output of all bushing engines, and this simply ain't so.

2) Bushing engines are designed to run pure castor oil lubrication. The ideal fuel for an O.S. LA series or Thunder Tiger GP series engine is 10% or 15% nitro with 20% pure castor for lubrication. The castor oil not only helps "float" the crank shaft inside of the bushing, but the extra thick viscosity of the castor oil also helps seal up the crank case and provides maximum compression for the engine's operation. Too many folks are buying all synthetic or 80% synthetic/20% castor lubrication fuel to fly their bushing engines. It's getting difficult to find all castor lubrication fuel anymore.

If you run any bushing engine with 20% lubrication all-castor fuel, you'll be pleasantly surprised by the performance. This type of engine will also last long enough to pass on to your kids someday so long as it is tuned properly and not dive-bombed into concrete.

Mr67Stang

Well said Big Ed.

downunder

What big ed said about bushings. Compare that to the number of times you read about rusted bearings.

As for ringed versus ABC...treated properly they'll both last about the same time but ringed is far cheaper to fix when they eventually wear out. Powerwise there's virtually no difference if the engine has an option for either like some models of OS have. The only limitation with rings is they can start to flutter in the groove over about 20,000 revs .

BarracudaHockey

My Feedback: (11)

Bruce, ringed engines are actually more tollerant to a lean run than ABx

JD380

My Feedback: (133)

I agree with BarracudaHockey. AB? have such a tight tolerance at/near TDC that any lack of lubed due to a lean mixture can make the piston stick to the liner, scraping off some of the chrome/nickel plating.
I wonder why someone doesn't make a chrome/nickel lined ringed motor? It would cost extra, but talk about a low friction. While still it's possible for the chrome to be damaged, it is much 'slicker' than a plain steel liner. I know it makes a difference on V6 outboard boat motors.

B.L.E.

I have a OS .15 FP that still runs but is down on power. After opening it up, I discovered that there was a noticable amount of play in the piston to connecting rod wrist pin bushing. I have never seen a crank bushing wear out.
Ball bearing engines still have bushings in the connecting rod upper and lower end.

There are a lot of applications where bushing bearings are the preferred bearing. Advantages include quietness and an almost indefinte lifespan. The shaft does not rub on the bushing, it floats on a thin layer of oil once the shaft starts turning. It's not uncommon to see still in spec bearing bushings in car engines that have 300,000+ miles on them.

armody

My Feedback: (10)

Thank you all very much for your replies,

Here in my country, I hardly saw anyone using 10% or 20% nitro, some I had the idea were using when I used to goto the other flying field. Here me and my friend they are all using 80%methanol 20% castor oil in all our engines. We are all using 2 stroke engines, and I'd probably gonna buy ASP .61 size, which is in my future list, or MDS .61. as soon as I get on job, one from a bank other from an insurance company. Anyway, Either ringed or bushings, both engines have the same performance, but why is it said that O.S.'s L.A. series is less powerfull than FX or AX series?

Mody

Sport_Pilot

Actually there is very little differance in both wear and friction between the two. In the past some very strong racing engines have used bushings, in fact if the fuel/oil is forced into the bushing so that there is some pressure then the shaft will not touch the bushing and will have less friction than a ball bearing, however the bushings in the low priced engines of today will have slightly higher friction. They last longer than many ball bearings, however they are not replaceable.

Sport_Pilot

Because they are timed to have lower performance, has almost nothing to do with the bushing and air bleed carb (other than the smaller size of the carb) They are designed to be lower power and cheaper. The bushings and air bleed carb make it cheaper, the timing and small carb size give it lower power. However, they are good torque motors. The control line modelers like them for that reason.

Sport_Pilot

Most of the time it will scrape off some of the softer aluminum piston.

B.L.E.

Well, let's start with carburetor venturi size.


OK, that's not the LA engine to the right, it is a FP engine that was replaced by the LA line of engines. Mostly the difference is square fins and rear needle.

If the FX engine was re-designed into a bushing engine, it would still be powerful.

AA5BY

One point not made yet is that ABC engines don't tolerate being run rich as the liner must heat up properly to provide the necessary running clearances but engines with bushings kinda like a little richer mix as noted by several comments above. For this reason I'd not choose an ABC motor without bearings.

I agree completely that bushing bearing motors are generally given a bad rap. I've bushing motors like an Enya .29 that is probably older than me and I'm not young (sixties) and it is still going strong and currently flying in a Sig Kadet LT-25 trainer for the grandkids. It starts easy and idles great but admittedly likely has less power than a modern .25 but in those days prior to electric starters, easy starting was a priority. And... regarding air bleed being non desirable, yep... the old Enya had air bleed idle and is one of the most reliable idling engines I've ever seen.

Perhaps my illustration just points out that there are always exceptions... but as someone else pointed out very well, one can't classify them all because of one either.

B.L.E.

There's only a few clicks of needle adjustment between rich and lean so I really don't think the bushing will know the difference. I think that mixture is used to fine tune the ignition timing of glow engines. This is based on my experience with changing the compression ratio of glow engines and noting that an engine with a lower compression ratio makes it's maximum power with a leaner mixture than the same engine with a higher compression ratio. The overheating of a lean mixture does not come so much from lack of lube but from the mixture igniting too soon as the piston moves up the bore.

Also, remember that in ball bearing engines, the con-rod still uses a bushing.

da Rock

Don't believe everything you read on the internet.

And our hobby is too complex to be described in a sound byte. Everyone always wants everthing to be explained in a sound byte. They want a very short, all encompassing sentence to be true for every aspect of some problem. It doesn't happen that way.

This sentence, "I read on a website that ABC engines are more powerful and good than Ringed engines. is a perfect example.

downunder

Actually they'll handle very rich mixtures (4 stroking rich) with no problem at all. I got all brave and tested this out on a brand new ABC running slobbering rich for 45 minutes and the piston wasn't even marked let alone starting to run in. CL stunt ABC's are run in a continuous 4 stroke for hundreds of hours with no harm at all. It's an internet myth.

Enya 29/35's however never wear out .

B.L.E.

A long landing approach with an idling engine will cool down your engine more than a rich mixture will. If your glow engine "goes lean" in the middle of a flight you can usually prevent the inevitable deadstick landing by throttling back. The engine cools off and continues running that way.

armody

My Feedback: (10)

Air Bleeding and carb bleeding means that carb is taking air or carb is expelling fuel from its side, as I have seen many times in my friend's engines which are O.S. .46 and .25? Sorry If this question of mind sounds little stupid, but I wanna know the real meaning of carb bleeding and air bleeding.

Second thing, Once again as one of our respectable poster said Dont believe in everything you read or see, thats true, but As I have a pretty pretty bad experience with my HB .61 german engine, and it made my plane crash many times. I'm using now K&B's .61 size engine with pump, but not using pump, it still gives me hard time. I noticed one thing, that new technology's engines are much more good than old one's or probably Im the one who is unable to set their needle valve setting despite senior friend flyer goes with me, but I know one thing for sure about his habbit once engine is set on high rev, he always slightly slows it down on lean, when we lift the nose up engine starts dying, if we do more rich, then it starts going pretty well. What I figured out so far that whether engine has bushing or bearings, whether it is ABC or Ringed, whichever engine runs good without problem, its the best engine, same can give hard time, and same can be the best for one.

Thanks for your input

Mody

TexasAirBoss

My Feedback: (22)

Once a ringed engine gets about 15 years old, its difficult to find rings. Even OS doesn't support the old 50SF anymore and it was a screamer.
I think just about all OS engines will be supported for about 15 years. Then finding parts can get sketchy.

I don't know how other companies support their engines.

AA5BY

I've an HB 61 PDP, an HB 40 and an HB 20... all continue to run great but they all have Perry carbs that are intolerant of the smallest spec of fuel contaminate.

bruce88123

I remember seeing an ad from a guy that makes rings for various engines but can't remember who he is. He would make a ring, to order, for ANY engine.

Cheap? No.