I have a brand new OS 32 SX w/tuned pipe... I'd rather break in the engine with the tuned pipe installed, but the instructions for the tuned pipe recomend breaking in the engine with the stock exhaust... What do you guys normally do that have tuned pipes? Break in the engine with, or without the tuned pipe?

Thanks,

Adrian

I WOULD FOLLOW THE ENGINE MAKERS INSTUCTIONS,AND BREAK THE ENGINE IN WITH THE STOCK MUFFLER.THE REASON IS THAT TUNED PIPES PUT MORE STRESS ON THE ENGINES,AND THEY ALSO MAKE THE ENGINE RUN HOTTER.THAT`S WHAT YOU WANT TO AVOID WHEN BREAKING IN A NEW ENGINE!

I usualy avoid Engine break in discussions as there is more nonsense than sense spoken and written.

However I must prevent you from destroying your engine, which you surely will if you follow the instructions so far given.

If you have purchased a high performance engine can I assume you have some knowledge?

basicly the engine should be broken in as it is intended to be used. Use the same fuel, Tank setup and exhaust equipment that will be used during it's operating life. During break in the engine must be brought up to it's operating temperature and RPM. This process should be carrried out with a rich two stroke needle setting. Do not let it four stroke. To achieve the required RPM with a rich needle use a smaller propeller than normal.

There is little point in "Breaking in" an engine rich and cool, and then sticking a pipe on it and heating it all up.

If you need more information email me.

I will not argue about this on the Forum.

Ed S

Follow the manufactures recomdations, then shoud the engine break durning this time you wont have to lie about it when sending in for repair.

I, would follow the instructions since that is the only guideline you have. Ed did not design or engineer your engine.

I can see no reason why breaking in an engine with a pipe is better or even prefered over the stock muffler. I'd stay with the standard muffler according to instructions, then move to and start tuning the pipe... However I would eagerly listen to "discussions" otherwise. I enjoy listening and learning.

This is my experience with the following engines all with tuned pipes
OS61VF
Webra61
ASP108
OS25

The OS61VF had no choice but to attach some type of pipe or muffler as it does not come with a stock muffler. That engine is designed to be run with a pipe from day one. I ran that engine with a tuned pipe on an appropriately rich setting from the start only adjusting the needle for seasonal changes. After more than 10 years..it is still a mighty power house.

The other engines came with stock mufflers; breakin and even well past breakin I used the stock mufflers till at least a couple of dozen or more tanks before attaching tuned pipes, ran a little rich, as the engines run at a higher rpm, established what rpm I want the engines to safely run (use a tach) and left it there. All the engines to this day are a blast to use and never miss a beat.

EVERYONE has different experiences with motors but I would stick with Pine Baron. He's been there, DONE THAT. Every engine chat has a know it all and Mr. Smith seems to fit the mold. The fact of the matter is, EVERY engine is going to react differently to how you break it in or run it for that matter. Baron does have some experience to speak of and isn't to "proud" to say so. I work with motors every day and have brought some model motors back to life that have sat "gumming up" for as long as 9 years and Baron and a few of the others here are playing it safe and that's why they aren't having problems. Break it in with the stock muffler as your tuned pipe instructions say, you won't be sorry.

ADRIAN,

I understand this can be a "heated" discussion!

When you are breaking in your engine, you want to keep the "heat" down, The piston to liner clearance needs to "seat". And in the case of a ringed engine the ring to liner must "seat", "seating" means for the metalurgy to "match up" it is actually a wearing in process.
If you drill a hloe in a piece of metal with a metal bit, you put oil on the piece you are drilling to help keep the metal cool so as not to cause excessive wear on your drill bit. the same works for other metals, if you get them hot they loose their hardness, heat causes metal to "anneal" or soften. I do this PROCESS almost everyday working with gold in my shop. You DON'T want to make the metal soft or harder you want it to maintain the same
"MOES"hardness that the factory put into it.
Try it yourself with a DRILL AND DRILLBIT! Drill into a piece of 1/2 inch steel with oil and without oil, notice that without oil you "BURN" a bit up! Then use that same heat process and thought to break in your next engine!

lOTS OF OIL "very rich"LOW R.P.M. = LOW HEAT!
I use a "break in" oil, 10% nitro, 80% oil,20%castor for a total of 20% oil mixture. , "PERFORMANCE PLUS" is still made to this mixture. you used to be able to get it at "hobby people".

Break the engine in as the MANUFACTURER TELLS YOU TO!

There is more than one way to do it, but they give you a guideline to help with any questions you may have. (AND AS ALSO STATED ABOVE, TO HONOR THEIR WARRANTY)
As far as the "tuned pipe" goes, It won't hurt to break it in on the pipe as long as you keep it "OFF THE PIPE" "ON THE PIPE" is a terminology used to describe when the engine and PIPE is "MATCHED" JUST REMEMBER the PIPE is designed to give you added R.P.M. and as stated above the added R.P.M. is going to produce added heat. IF YOU DON'T UNDERSTAND THIS, BREAK THE ENGINE IN WITH THE FACTORY EXHAUST.

Any questions, please feel free to E-MAIL me or send me a P.M.

I MEAN NO DISRESPECT TOWARDS ED SMITH! Just don't agree!

Friends I fly with ran new engines on the ground in the airplane/helicopter at the time they are going to fly it, then they put it "IN THE AIR" I can show you an ENYA 35 HELI engine that was done this way, It needs a new piston and sleeve! also a T.T. PRO 46 That was done this very way, The guy "gave" it to me because it was a "BUM" engine, I sent to THUNDER TIGER for a PISTON,LINER AND BEARINGS. I've been running this engune for three seasons now, ON A MAC's PIPE, it's a power house! The guy keeps saying that "his never ran that good!" I WONDER WHY?

RON in NEVADA

[email protected]

It should be easily understood why I wrote the first sentence in my original post.

A "Know it all" I am not, I never claimed to be. I do listen, read, participate and learn, unlike many other "Engine experts".

For the past ten years I have participated in F3D Pylon Racing. The engine for this event is only a fully tuned pipe unit. To this end I have reworked my own engines, modified pipes and molded my own propellers. I do have knowledge on the subject.

Fear not, I will never again attempt to dilute peoples ignorance on the subject of engine break in.

Ed S

Ed,
New to the hobby, I am always willing to accept new concepts and ideas. Some I can see some reasoning and others I need a little more explaination. And I am not "arguing" Ed, but wish to know how breaking in a new engine with a stock muffler by the manufacturers reconmendation can ruin an engine when one then installs a pipe? Thanks for your help.

Quote:

"However I must prevent you from destroying your engine, which you surely will if you follow the instructions so far given"

I too am new to the hobby. And since I am about to break in my second engine I have been following all the break in threads with interest. My engine came with a pipe. So I don't have a choice here. It will be broken in on the pipe.

Here are a few things I have gathered about breaking in a ABC engine from various sources:

1. If supplied, follow manufacturers' instructions. They should know what is best for their product.

2. During initial break in you are primarily breaking in the connecting rod bearings and journals. The piston and liner are not the primary concern during breakin. There is nothing to 'seat' on an ABC piston/liner. The piston/liner will wear itself in during normal operation.

3. You want to break in the engine in it's normal operating temperature range. 230-270 degrees or three quarters to full throttle. Under no circumstances would you want to idle the engine for extended periods. The piston and liner need heat to expand to their proper tolerances. As soon as the engine fires up bring up the RPMs and get the engine to the proper operating temp as fast as you can.

4. Sloppy rich or four-cycling is bad. You will damage your connecting rod and journals. Run moderately rich.

I think all this makes sense to me sofar. I should be ready to break in my engine this weekend. If I left something out please let me know.

Tom

So you guys MIGHT listen to what little advice I have to offer, I offer up the following qualifications.

I have been RCing for over 30 years.

I port, balance (yes, you CAN balance model engines to make them smoother) and modify most of my engines especially the ones I use in my other passion, RC cars.

I built and use both a thrust measuring device and an inertia dyno (similar to a DynoJet Dyno) to verify the results of modifications I make to Glo engines.

I have a complete machine shop in my garage / shop. 3 years ago I even ground a set of cams for a Saito .91 with increased lift and duration. (It runs strong but is NOT worth the time it took)

I build most of my own tuned exhaust systems.

Until recently I owned and operated a full size DynoJet Dyno mounted in a trailer (DynoWorks) which I towed to motorcycle and quad races all over the Pacific Northwest. I have been building high performance motorcycle and ATV engines for almost as long as I have been RCing.

So back on 12-24-2001 I posted the following on this site. It is based on all of my experience plus what Clarence Lee and Dubb Jett have to say on the subject.

This is EXACTLY how I "run in" my new engines (and rebuilt ones)

================================================== ===================

The OS 32 is an ABC type engine which requires a different type of breaking in than a ringed engine.

ABC engines need lots of heat in the cylinder to operate properly.
EXCEPT on the first few runs when the piston needs to wear into the cylinder which is "breaking in". Running it "rich" helps keep the new and tight piston / cylinder assembly cool which causes it to wear rapidly which is what "breaking in" really is, RAPID WEARING of the engines internal parts.

The engines lower end does not need any sort of running in as the precision with which engines are made these days precludes it.

With an ABC engine you need to run it up to almost max RPMs with the needle set rich so it stutters in what is known as 4 cycling.. Do this once for about 3 min then shut it down and allow it to cool completely. This creates rapid wear of the piston / cylinder assembly. Now start it again but this time lean it out (needle turned in) so it alternates between 4 cycling and 2 cycling. Run it for 5 min like this and again let it cool completely. Do this 3 to 5 times total and your engine can be flown at almost it's maximum. These runs continue "wearing" in the piston / cylinder but at a lesser rate.

The reason you want to heat and cool the engine a few times is this allows the alloys to expand and shrink and finally seat in place.

A tuned pipe will make NO difference to the above process. A tuned pipes benefits (and short falls) will not come into play during the 'running in" of an engine.

================================================== ======================


Wanna know a quick way to partially RUIN a new engine??

Run home from the Hobby shop with your new engine in hand. Quickly remove it from it's box, install a prop and then proceed to turn it over a few times (plug installed or not doesn't matter).

Here is what doing the above MIGHT have done to your "new" engine.

IF the engine has been sitting for any length of time since leaving the factory any assembly oil has probably evaporated so the internal moving parts are rubbing against each other sans lubrication. The resulting "metal to metal" rubbing can do serious damage.

Secondly, during the manufacturing process some foreign materials might have remained inside the engine when it left the factory. Imagine what a tiny piece of metal shavings can do to the piston / cylinder as you "spin" your "new' engine.

A quick note about finding foreign material inside new engines:

You won't usually find this to be a concern with the premier brands such as OS, Saito, YS etc.

BUT

Did you know that the American importer of Moki engines disassembles all of the engines shipped to him from the factory so he can clean them thoroughly? He is in business where time is money so I'll leave it to you to figure out why he does this to EVERY Moki he sells!!

In my experience ALL engines should be at least partially torn down (remove the back plate at the very least) and checked, especially ones made in the former USSR and the far east. (China - ROK - Hong Kong etc.)

Then before starting for the first time, squirt a little fuel in the glo plug hole and some into the carb. Turn the engine over slowly by hand a few times to distribute the fuel (which contains lubricating oil). now you are ready to start the 'running in' process.

If you don't know how to do this, find out!! Harry Higley has a great book on teardown and assembly of model engines.
Don't be a "tight - ass" and spend $100.00 on an engine but not $15.00 on this book.

I hope the above info helps.


BTW: I add 3 to 4 ounces of Castor oil to all of my fuel. Check the latest issue of M.A.N. (Model airplane News) to find out why.

I tear down my new engines as well. Some will say it's a waste of time because the manufacturer's warranty will cover any problems that may arise but for me packing up and sending back an engine is a waste of time. Spending a couple of hours on a new engine sure beats waiting a couple of weeks for warranty service.

Another thing I like to do is measure and record the major dimensions such as bore & stroke, bearing dias., port timing,etc. I have a log book I keep this info in. It's a great help when you need bearings or want to try a different carb or want to do some port timing changes.

GUNSHIPGUNNER - do you use any software to help you with your engine modifications?

I HAD some software I used but lost it (and lots of records) to a computer theft a couple of years ago.

This included ALL copies of my DynoJet Dyno runs. As luck would have it I had managed to upload some of my database to the DynoJet site.

The software I had was designed more for 2 stroke motorcycle engines but some of the parameters like rod angle, compression ratio and piston speed were directly applicable.

If my memory serves me, the only software I came across in a recent search of the net cost around $100.00 and $100.00 will buy a nice airplane kit thank you!! (and it was written (I think)
for RC boat engines)

My records are now kept burned on CD in Word for windows.

I surely would like another shot at some engine mod software.

BTW: I used that engine balancing info that the helicopter guy from RCM wrote up (originally from a Russian control line racer) and it works well but requires the removal of a lot of material from the stressed areas of the crankshaft. I read where the control line fast guys are spinning their engines up around 44,000 RPMs (Yes that's FORTY FOUR THOUSAND) YIKES!!!

Take care!!

GSG

That's some really good info. Thanks. I don't mean to be argumentative, I am trying to learn here. I would like to ask some questions.

First the lower end run-in idea came from Dubb Jetts' break in instructions. I am not really that concerned with what specific part of the engine is being broken in. I just want to do it right for the engine as a whole.

The part I am most concerned with is how rich to run the engine.
You state that on the first run you do want to run the engine four-cycling rich. Does that apply to high compression engines? (Irvine, MVVS, Rossi etc...) My Irvine instructions specifically state not to run the engine that rich at any time. According to Irvine, connecting rod, rod bearing and journal damage will occur.

The reason I ask is because I am breaking in a Rossi. The instructions are in EnglItalian. So I have to fill in the blanks here and there. Rich, or 'greasy' as they call it, is a vague term to say the least. So I figured the Irvine instructions would apply here.

I have another question. Judging from all the tweaking you do, engine longevity is not a major concern. How long do your engines last?

Tom

P.S. I do agree with everything else you said. I already inspected my engine for metal shavings. I will go out and get a fresh gallon of fuel and add 4oz of castor to it. And no, I did not put on a prop and turn the engine.

Well, here's my 2 cents. This is a good illustration of what "rich" is. A couple of years ago I was breaking in a new O.S. 45 FSR (was a lucky find - or so I thought) running it rich but NOT 4-cycling because it was an ABC (nickel plated, actually) engine. Within a few minutes I heard a funny noise and noticed it loose RPM. I brought it to idle and revved it up a few times to get a close listen to it and then shut it down in confusion. What the heck went wrong? Well, I took off the backplate and found that the rod bushing at the big end spun. It didn't stick to the crank pin but there were aluminum shavings everywhere, even in the combustion chamber! My first fear was that I scored up the nickel plated cylinder. But when I diassembled the whole motor I found that there was oil everywhere and all the shavings were suspended in it. There was not one scratch on anything! Not even the top of the piston! Fortunately, I had another connecting rod so I cleaned everything up, even the bearings (had to remove them and flush 'em out with soapy water) and when I put it all back together it ran like a champ. Should never have sold that engine!

So, when the manufacturer tells you to run it rich or "greasy' when breaking it in it doesn't necessarily mean the engine has to be running rough or 4-stroking. A rich 2-cycle passes plenty of oil through the engine. Well, unless you got a Fox .35

Can we argue about this a little bit? I don't see how it is possible to destroy the engine if it's put on a tuned pipe after it's been broken in... ? Are you saying the engine has been heat-tempered with the stock enhaust, and now the tuned pipe will change the heat-tempering that I've already established with the stock exhaust?

Adrian

But there are some practical considerations when using a pipe...

I run the engine open exhaust to get a base-line RPM reading before putting the pipe on. I find it helpful to know what the engine was turning without the pipe, so I may know how much gain I am getting with the pipe, as well as where to stop when getting the pipe set.

So if I am running the engine at a fairly good clip with open exhaust, I am running my engine in.

Then I mount the pipe and set it....this takes a few more runs, and the engine will cool down in between runs....just like breaking one in, no??

As for Deadmeat and the Rossi...these are the easiest engines to break in IMHO...fire it up, get it running WFO, back off a few clicks, let it run, shut it down, repeat. Then mount it up and fly.

I've done this with every Rossi I have ever run, modified or not, and have never shelled one. They have very large con-rods, and the cylinder/piston are about as bullet-proof as possible.

Take this post with a grain of salt (or a cold beer), I'm not trying to tell anybody that they have to do it this way, but it has worked for me. YMMV

Dave,

Apparently you haven't been around Pylon Racing or know much about engine performance. The reasons Ed recommended the way he said was because it apply exactly as how the engine was intended to be run/use.

As adrian was saying.... He purchased the OS 32 SX w/tuned pipe. If he intended to run the engine as equiped, he needs to break-in the engine accordingly. Just like what Ed was recommending per his written notes.

Yes. The manufacture recommended with stock exhaust, but what will the stock do if it was intended to run differently. The manufacture will usually recommended with the safe feature in mind due the fact that most Sport flyers doesn't have a lot of exeperience with engine tuning. Therefore, they make sure the recommendation is an easy one for Sport flyers to do.

But to make judgement about Ed's not an Engineer or Designer would be putting down someone who have tons more experienced than yourself would be of ignorant. To get all this straighten, I've put a link to Engine Break-in for your/others to reference by. Hope this will help others as well.

Engine Break-In

Go to "Tech Specs & Instructions" and click on a link FAG (Fequently Asked Questions) page and to Engine Break-In.

http://jettengineering.com/

Sam S.

Mighty Mouse,

The statement was made by Ed was in response to THOMKP J as it was written below...


"I WOULD FOLLOW THE ENGINE MAKERS INSTUCTIONS,AND BREAK THE ENGINE IN WITH THE STOCK MUFFLER.THE REASON IS THAT TUNED PIPES PUT MORE STRESS ON THE ENGINES,AND THEY ALSO MAKE THE ENGINE RUN HOTTER.THAT`S WHAT YOU WANT TO AVOID WHEN BREAKING IN A NEW ENGINE!"

Sam S.

Hi Gyz: So far this thread has been interesting, and informative.

Let's also remember to keep it civil.

Thank you - Jim Lynch, Moderator.

SS, I have broken in over 80 engines, probably a hundred counting other peoples I've broken in for them and have not messed one up yet. I broke in two Fox Eagle 74's with stock carbs and quiet mufflers then put a Davis Diesel head on one and a Perry regulating pump and Perry pump carb and Mac's tuned quiet pipe on the other. Neither blew up or over heated when changed to the new use. I believe this should end any discussion about my being ignorant.
PS, Thanks Mr. Lynch

I broke in my OS 32 SX with the tuned pipe tonight.. I put about 2 takes of fuel though it... Wow, this thing screams! 14k with a 10x5 APC prop... My little delta-wing really moves with this engine...

Adrian

Hey Sam,
I am sure Ed was trying to help. And I have spoken to him offline and enjoyed his procedure on breaking in . I really dont think he meant "destroy" as in total destruction, but that he believes in a better procedure thats all.