Typically the engine manufacturers make a specific recommendation with their engine on how many gallons of petroleum oil premix to burn before you switch to synthetic. One of them cautioned their customers against using synthetic oil during break-in because they were having a problem with the cylinders losing compression. One cylinder would quit firing on a twin because of low compression. They found that if they took the engine apart, soaked the cylinder and piston in acetone to remove all traces of the synthetic oil, they could get the compression back by running the engine on petroleum oil premix.

Well on the other hand though, there are distributors who have recommended using synthetics. I know I said distributors but the engine manufacturer evidently themselves have agreed to this method or else they couldn't make that recommendation or could they? Atleast this distributor has.I believe they can make that kind of recommendation because 90% of their motors are serviced in house instead of sending them back to the manufacturer.I believe the manufacturer has total confidence in the distrubutors ability to diagnose, represent,and service their motors without questions , simply because of the distributors knowledge on their egines.

Diablo,
I have converted your original post to a page on my website. Please take a look and let me know what you think!
Great information!

http://www.geistware.com/rcmodeling/...s_break_in.htm

Again Fryfly is mis/ill informed and relating things he knows little about. .

We use ASHLESS oils in our engines. . oils containing NO SOOT. this is because an "Ash" oil leaves behind deposits inside the combustion chambers that very quickly form carbon, buildup, and can cause pre-ignition or detonation. EVERY model engine manufacturer/supplier says to use ASHLESS oils.

Our engines have TIGHT clearances in the bores, whereas NASCAR engines (I used to build hi-po motors and live next to a NASCAR race shop) have very loose clearances in their piston-bore area. . usualy on the order of .0025-.003" at least, and as much as .005" in some cases. What do the NASCAR teams run?? 50-60 weight RACING oil, petroleum based for the most part but some synthetics, and they cool it with a cooler and use dry-sump systems operating at over 100 PSI at 7,000+ rpm. EVERY NASCAR engine is test run in on a Dyno or engine stand for 8-10 hours before it ever gets inside an engine compartment. There are no green bores, fresh ring facings or unbroken in engines in the car haulers and pits at a NASCAR race. how are the engiens broken in? A very methodical run-in is done, with 5-6 periods of running, to check the motors out and break them in and let them heat cycle a few times to let things settle out.

It's nice to be able to cut and paste selected information gleaned from a website so that everyone else can read it, but it also shows that the recommendations concerning proper break-in of our engines (as suggested by the manufacturers) , that is, to use 32:1 - 50:1 ashless petroleum oil for 8-10 gallons for proper break-in, then switch to synthetic after that, is exactly what the SAE recommends for this type of activity.

It kind of makes you wonder if these "suppliers" of engines, rather than people who actually BUILD them for a living, know what they are doing. Anyone can be a salesman, but few KNOW their product well enough to be able to tell you exactly WHY it does what it does, and how best to get the most out of THEIR design. Thanks, I'll listen to the people who designed and built the motors I use . . .rather than some wannabe importer who will say whatever it takes to make a sale.

I have read some 2 stroke synthetic oils do not leave a real good coating in a engine. If engine is not going to be run for a week or so, it says (on container) to use a shot of afterrun lube to prevent rust. What say-thee about this??? Thanks Captinjohn P.S. I do use after-run lubes of various types

If it's in a gas-oil mix, I find it a bit strange, but do not doubt it. If the label recommends it, I'd follow the directions. A shot of WD-40 ought to do the trick. .or maybe you'd prefer to mix an ounce or two of Castor into your gas??? hahahaha

Hey Kris,
Good reply, I used to do quite a bit of small engine repair on the side ,and your correct about the tighter tolerances etc,etc but
only on the" real as designed for aircraft use" motors. My comment I guess was aimed at the "conversion " stuff.

My error, good catch.

BTW...........this may sound a little silly,but what the hell.

I do "run in" ALL of my internal combustion engines prior to
using them, this must be a carry over habit from my Fox CL
days in the 50's and 60's

My best regards
Roby

Anyone who thinks MOST, not ALL, gassers made here in the US of A had pistons and cylinders designed and manufactured to their own tighter(?) specs for aircraft still believes in the tooth fairy...
Manufacturers want us to think they're unique..How about some of the major manufactureres telling us where the parts REALLY come from ?????
Echo, Stihl, Sachs/makita, and Husqvarna..Most 2.4, 3.2, 4.2, 5.8 singles are Sachs parts..Most 4.8 twins are 2.4 Sachs parts, 6.4 twins are Sachs parts, 8.8 twins are Husky parts..11.6 twins are Sachs parts...Quadra Aerrow parts come from Partner/Pioneer/Poulan...Zenoah ? Red Max lawn and garden equipment...U S Engines? formerly chainsaws...
99% use Walbro or Tillotson carbs..I can tell who the carb was made for (manufacturer and model number) by the part number stamped or cast into the carb.....Walbro WILL customize a carb and make it proprietary if any manufacturer would buy enough to make it worthwhile..Most companies use the carb made for the original application..Witness the WT76A made for the 3.2 Sachs...4.2 and 5.8 engines use SDC 80 carbs..You can call Luis Salas at Walbro for info...They do it for Stihl chainsaws ....
How about it guys.. A Little truth in advertising ??
FWIW..Nikasil as used by 3W and some others is harder and smoother than hard chrome....

Roby: Are you saying comversion engines are not real aircraft engines? Or are you leading us to think a converted engine is not up to par with what you call real engines. There is always someone around that can build a stronger running engine than a production built aircraft engine. Captinjohn P.S. Kris some synthetic brands oils did add caster

We use Klotz Super Techniplate(80% Syn. and 20% Castor) in all our gas engines mixed at 50/1. We have about 25 engines of ALL makes. We took apart a cheap US41 after about 200 flights and it was clean inside, with no wear that we could see. These engines are run on this diet from day one. Hey, ya gotta stick wit what woiks.

Couple of quick points, if I may.

First of all, companies such as 3W, DA, BME, and ZDZ do use totally proprietary parts for their engine designs. BME is currently switching to it's own cylinders, so you can say good-bye to the Echo chainsaw jugs. Are these pieces better? worse? no different? .. let's just say they are optimized for what WE do, according to their producers parameters and requirements. The current BME102 "Evo" is very close in power to the DA100 and old-style standard 3W100, as well as the Brison 6.4 (using Sachs heads), and the BME used Echo jugs . .they worked, and still do, and are a perfectly good piece. 3W started life using converted chainsaw jugs, Brison continues to do so.

The guys designing their own cylinders with proprietary porting and running characteristics are going for power THEIR way, not the way Echo, or Sachs or someone else dictated when they designed a leaf-blower, weedeater or chainsaw. Does this make their products "Better"? No, not really, just more closely focused on OUR market.

So, take 3W, DA, ZDZ and BME. .NOW the only part they have in common with a chainsaw is the carburetor, be it Walbro or Tillotson. Why?. . simple economics. . YOU go out and tool up a carburetor for these engines .. then sell it for $25/copy the way Walbro and Tillotson do to their jobbers or resellers. It's not going to happen. Getting on the case of engine bulders because they use a commonly available carburetor (that is probably slightly "tweaked" to their specs before shipping) is pointless.

As for engine "breakin". . it is, in the end, up to the consumer. . but these engine builders do not recommend a certain type of break-in procedure just for the sake of it. They do it because it has proven, time and again, to be the best and most consistent way of making sure that their product gives the best power and longevity possible. That's what the customers want. . that's what they try to supply.

A last note. . I see $30-50,000 cars all the time that are totally worthless or abused to the ends of their useful life. . why? because the OWNER did not follow the manufacturers service recommendations. . .. seems to me that if you follow the manufacturers directions, you can't go wrong. . they sure aren't going to recommend something that is going to ruin their product.

Gentlemen,

This thread has in fact displayed that most of us have our opinions and that opinions are just that. I do not see the benefit from slamming one anothers posts bordering on insult as being a beneficial addition to the forum.
Be that as it may, I believe that regardless of the method one desires to break in their engines, with care they will all have a nice running engine in the long run. The synthetic users will just take a bit longer than the non-synthetic users. Is anybody absolutly right or wrong? - No I don't think so.
This is a hobby and a fun one, we all know that there is more than one method to achieve an end objective.

Synthetic oil break in or conventional oil break in? The great debate will continue.

Now for my opinion on the subject. I am one of those that subscribes to the synthetic only school of thought. Yes, it takes a bit longer to get a really well seated ring. I also am a firm believer in heat cycling the engine for the first hour or so and running an oil mixture a little richer (32: rather than 50:1) for the first hour or so. I also vary the load on an engine and (on airplane engines) swap props to load the engine or unload the engine and run it at different rpms. I will run the engines at high rpm and light load for a short while and then load it down with a heavier pitch and run a high load and lower rpm's.

My method works for me and that is my opinion from experience.

Hellow Dr Nitro: I do not think slaming is shown here to badly..... just some lively debate. I would rate this thread very good. Why? Because there is a lot to be learned when others read it. Any more opinions is just icing on the cake!

Dear Captinjohn

My point is (or was) that usually when you do a conversion,no
matter how well done, is not as good as a piece of equipment
that was designed from the "ground up" to do that same job.

An adapter is an adapter no matter how you look at it.
I'll admit that many of the conversions work ,and work
well. A big bang for the buck, but not nearly as good as a
(ground -up design)motor that was designed to spin only
a prop within a specific range.

Kris was very correct about some of the engines (wackers, etc)
out there. My point there was if you would't break in your
trimmer then why would you break in the same motor that is
converted into aircraft use other than to see if it will still run ?

I must be missing something,

Regards
Roby

Read my very long post above somewhere..There are very few "designed from the ground up to spin a specific prop at a specific rpm" engines out there..Using chainsaw parts with a different crankcase( which is what most of the so called engine manufacturers do) does not consititute a built for a specific purpose engine..
I will put one of my G260 Zenoah "CONVERSIONS" up against any "built for a specific purpose" engine of comparable size (somewhere around 30cc) for thrust..Run any prop you want on yours, mine will run an 18-6 Mejzlik...
If you can find a 3 lb(muffler, ignition system, and battery (INCLUDED) engine that make as much thrust as my underpowered(?)conversion Zenoah, bring it on..Any takers ???
Using the very same chart, (ThrustHp) my Zenoah is better..We all know the chart is wrong, but good for comparisons between props, rpm, and engines.....(and conversions)
Good for BME, designing their own cylinders..Competition is what we needed to get to this level..
Still hard to believe a 50cc engine can weighs only 2(?) lbs...
Hope they can pull it off

Roby: I do not know what you are looking for....so I do not know what you are missing? You mention trimmers, weed wackers ect. Chain saws have much more power. Ever watch a contest how fast a modified one can cut a very big log. In the contest the engine has to start in one pull. Saw is on the ground and operator has to grab saw and start it on a very quick pick it up to cut log. What I am saying our airplane engines got to do about the same thing. That is to start and run strong. I would venture to say your so called dedicated airplane engine builders used much of the same parts and technology. I am very glad there is RC people out there converting engines.... it keeps the big boys from charging anything they want. Thanks Captinjohn

The ZDZ40, BME 50, BME55 Xtreme, DA50 all weigh under 3 lbs, with the BME's and DA turning 22" props at will.

Not really a fair comparison to a Zenoah g-26, but not really much more expensive either.

Thanks Geistware for finding the info of value and posting on your website.

Captionjohn

What a thread huh ? Some very interesting points of view.

Yes I agree chainsaws do pack a punch,Ive had several
from 2 to 7 cid. Never did "adapt" one for my airplanes.

I wonder, if you bought a chainsaw would you break it in
before using it to cut firewood ? If this same engine (new)was
converted for aircraft use,would you break it in before flying it
other than to see if it still ran after the "adaption process"?

This is the same question I asked back a few threads.


Just an observation but,
Most people don't or won't "run in "a internal combustion
engine except when it gets a prop mounted to it. Then and
only then does it become an issue "of highest concern".

As far as the adapted/converted engine opinion..............
well ....maybe your right.....perhaps I was" poisoned "when I
was taught and apparently learned all too well that a "ground
up "design if done properly will work better than a "adapted
converted " device. But hey, in this case the converted stuff does work I
have to give you that.

The above lesson I mentioned......................don't tell anyone,
but the people at GM must have missed that class when they
decided to "convert/adapt" a V8 gas into a diesel . It doesn't
apply here I know but it's just an extreme example of the "poison" I got.

Sorry about that
Roby

very good point Roby,Most engine manufacturers factory bench run your engines anyway, 3W,Brison,BME,Fox,Taurus,Zenoah,don't know about DA,or ZDZ though,I would imagine they do-atleast I hope so! These things are run enough from the factory to stress relieve them and check rpm's and to set needles enough to get them out the door to you and me. By the time these motors reach you they are run enough to start running synthetic oil.
Many OEM's are starting to run synthetic directly from the factory as factory fills. In fact some of the manufacturers state directly in warranty that warranty is void if synthetic oil is not used!!!!!!!!!!!Kris being a master mechanic should be able to agree with me on that one.
These motors are run at factory for stress relief/just like our RC motors
These motors are run to ensure reliability in starting/just like our RC motors/
these motors are run at factory to ensure they are good enough to take to the public for sale/just like our RC motors
and every other 2 cycle motor on the market today.

Ther isn't one single motor out there that is not factory tested /or atleast it's supposed to be before you get it,from chainsaws to weedeaters.
and YES our motors can be compared to larger motors with very tight tolerances. Our motors are too and even more so than 90% of the vehicles on the road today!! Our motors are machined to EXACT TOLERENCES, these engines are made to run at 6000 to 8500 rpm's,Most vehicles on the road today can't hit 6000 before the valves start to float,and the ones that can like the Corvette,some of the Mustangs,Lotus's,Masda's,and some of the German made automobiles come straight from the factory filled with synthetic motor oil. Not only are they factory filled but some actually state that warranty is void if synthetic is not used!! Our RC motors rate right up there with the best if not better.I don't think anyone here has a stock V8 that will hit 8500 rpm's and hold it for 10 to 15 minutes and not fly apart! I have a motor that will do exactly that and it's sitting in front of my model airplane,and guess what-- it has never seen conventional 2 cycle oil except in the factory where it was first run!!
Over the last couple of days I have done a little more research on synthetics and have also contacted an expert on synthetic oils. His name is Emery Layton a synthetic engineer,he works for Gulfside Synthetics based out of Baton Rouge Louisiana. He is more than willing to answer questions or send you any info you would like. His email address is -- [email protected]
he pointed me to a few articles that I thought were very interesting you might like this one.


article is from Muscle Mustangs and Fast Fords Magazine, with additional commentary by Performance Oil Technology, L.L.C.

Have you ever heard the story about the light bulb that doesn’t burn out or the razor that never dulls? Sure, these stories get exaggerated, but sometimes there’s an element of truth to the rumors leaking out of a manufacturers skunkworks. One particular rumor that sounds too good to be true is “an experimental motor oil that increases horsepower, practically stops internal engine wear in its tracks and improves fuel efficiency.”

Well, synthetic motor oil is not a rumor. It’s been in use ever since World War II (the Germans used it on the cold eastern front because conventional oil wouldn’t flow in the arctic-like weather). Even though it sounds too good to be true, synthetics do reduce engine wear, improve gas mileage and increase horsepower.
Interestingly enough, the biggest reason that synthetic lubricants are not in widespread use is because the would-be consumer does not know of the benefits provided by synthetics. Also, they are not sure where to go to ask or who to ask. You should seek out and acquire information from a Certified Lubrication Specialist, lubrication engineer or unbiased automotive engineer or competent mechanic that fully understands and can explain the benefits of synthetics and the drawbacks of mineral-based oil to the consumer. But beware, there are many mechanics out there that are so engrained in the old way of thinking that they refuse to change their way of thinking or even open up their minds to the fact that there are automotive engineers, lubrication engineers and chemists that know a heck of a lot more about motor oils, filtration, vehicles and synthetics than them

that being said remember that our engines are factory run/or atleast their supposed to be, to be stress relieved and needles set so that when we the consumers get them they are ready to goooooooooooooo!

there are alot of articles about synthetics and if you look deep enough you can find conflicting reports that go either way. And by the way Diablo I didn't mean to say your books were as old as dinosaurs I know your an engineer even though your articles have been published in the past few years there has been research done that almost puts that material out of date already.Atleast where oil and wear is concerned.
Our Radio control engines are at the top of the heap as far as 2 strokes go and far out perform the top of the line factory V8 comparible in size mind you, Why wouldn't you treat it the same way. Old school ways still apply these days and probably will for years to come/maybe, but that certainly doesn't mean that new school ways don't work/or won't. The proof is in the pudding!!

Factory run ?? Right..Tell that to the people who can't get their engines started because the needles are set too lean.Or the ..Or me, who fixed a bunch of US engines that had a porosity under the carb and had no pulse, therefore no fuel to the carb..Or Zenoah, who sent out a bunch of G62 engines with a casting porosity under the carb, right into the pulse hole..No pulse, no run..Or the 3W with casting porosity under the reed cage...
Or the person who got a ZDZ opr RCS with the carb gasket covering the pulse hole...Or the US 41 with no loctite on the prop hub that spun off with the first touch of the starter....Factory run ?? You believe in the tooth fairy ?? I have converted many NIB Zenoah engines, none of which were run prior to shipping..
I would recommend you look on Toni Clark's German website, read about Zenoah engines....
Top 2 stroke technology ?? We can only wish..
Motorcycles,, Jet skiis, and snowmobiles are way over what we have....AND... Dub Jett's glow motors..Try finding a gasser 25,000+ rpm..
Honda had a racing 4 cylinder 4 stroke that turned upwards of 20,000 rpm..

Chainsaw break-in? You all are correct that probably very few if any people break-in a chain saw. But, that doesn't mean it's the best practice for either long engine life or top performance. Most people in the US carry a 40 lb spare tire around their waste. What does your Dr. say about that?

Most people wouldn't notice the benefit of proper break-in. The ones that do understand what a leak-down test means.

I didn't say there were no lemons! I pretty much think we have all had lemons before,That doesn't mean that what I have stated is not true.I know for sure that Brison, BME,and 3w will give you stats on the engine RPM readings with a specific prop they run if you ask,If I remember right Brison puts the rpm rating on a tag with your engine,atleast they have in the past.I fly 3W and that's all I fly and I have had a lemon in the past too but that doesn't change anything that the manyufacturers do. They do run the motors regardless if you believe it or not.

I give up ....

I guess I shouldn't speak for Aircraft International as I'm not sure the way they do things.I get my motors from Cactus and have specifically requested my engines be run before they are shipped.If you guys are running engines that have never been started/tested before you recieve them I would ask that it be done for your own protection. I give up too!