I searched but couldnt find info on this, if its somewhere and I missed it I apologize for making a new thread. I have a OS FS 52 Surpass and I put a new piston ring in it, do I have to do the break in again? I didnt replace the sleeve just the ring. Thanks in advance!

If you go into the glow engine forum and then into the OS support you can ask Bill Baxter for a correct answer. I run a tank through the engine after a new ring just to get it seating then fly the plane. Just because that's what I do doesn't make it the correct way. Bill can give you a truly correct answer.

Replacing a ring requires a new break-in to seat the ring. Whether the sleeve is new or not doesn't matter. In fact, It may be more important when working with a used sleeve, as it will have deeper scoring that the new ring has to match up to.

Awesome! Thank you much

Run in as per the instrucrtions, switching between lean and rich and junk or just letting her rip?

I would follow the manufacturers procedure. Perhaps you could cut out one tank of fuel, and have longer lean runs, but if the head temp gets too high, I would richen it up quickly

A little background trivia here... as proven wrong, but it was interesting nevertheless.

When I was much younger.... (very much younger), there was a toy called a "Slinky". According to legend... the slinky was originally an easy way to transport piston rings in World War II. The engines in many of the vehicles were pretty much the same.... consider the mass production of planes, ground vehicles, ships.. (not that ships used the same engines, but the point is there).. the mechanics in both the European and Pacific theaters spent a lot of time rebuilding engines. Part of that was replacing engine rings.

The legend was that engine rings were not manufactured individually. They made these spring-like gizmos... not called The Slinky, by the way, that the mechanic could snip off a circular "ring" and put it on a piston, and quickly and efficiently get the engine back up and running.

Now, what I've read, this is nothing more than historical fiction.. however, it does pose interesting viewpoints of how these "Slinky's" were used during WWII.

Wikipedia disclaims this. But, we know how they lie!!!

CGr

It's total nonsense. Why did you post it?

If you go into the sense of humor forum they have a vendor there that will sell you one.

He posted it because he has a sense of humor.

If you don't like it, don't read it, and don't reply. It was just keeping things lite with some useless trivia. Get a life.

Ha... you leave such a post then log off. We got your number.

CGr.

You guys were sure rude to the new guy!! Oh, wait a minute!! Never mind!!![&:]

The new guy is ok. It's pompous folks that are the problem. Ooops... sorry about that. I'll have to delete my own post.


bob8619: I've owned that engine but never replaced the rings. I would guess that it would ge good to seat the new rings in.. and it certainly cannot do any harm to run a couple of tanks of fuel through it to make sure that they are seated properly. The cost is a few dollars worth of fuel and about an hour of your time. Wait... fuel IS expensive... just kidding.. I hope you appreciate humor.

CGr.

Oh I appreciate humor, I saw no harm in your slinky post, I found it pretty interesting true or not.

Bob:

To be honest, I thought it was factual until I researched it a bit. It would make sense if you think about it, but it was one of those "myth buster" types of things.

Now, I CAN tell you, with fact and personal experience, that these steel "slinkys" will work as a "log periodic antenna" for some of the amateur radio operator's frequencies!!! The transmitters will load up to them quite nicely Stretching them and measuring the length of the stretch will work just fine I have a friend/co-worker that uses them for the MARS system (Military Affiliated Radio System) in that he provides phone patches to our military serving overseas with the local link using such an antenna.

Regarding your "let her rip" comment, well, there are some that swear that you MUST break the engines in on the ground.

I learned by experience, that the first few tanks of fuel can be run through the engine either on the ground or in the air.. with some engines. I've done it either way.

Bench break in or just putting it up and flying it.... either will work.

Don't get me wrong.. I usually profess that you should do it on the ground, but there are alternatives. I you set the mixture to a comfortable point, yet somewhat rich, and fly it with the expectation that you won't get the maximum performance for a few flights, then you can fuel it up, start the engine, taxi, take off, and fly for 10 - 12 minutes (fuel supply sets that limit) then landing.. repeat any number of times... you will, sooner or later, break that engine in by default.


CGr.f

In the manual it says to go from lean to rich to lean to rich basically, whats the point of doing that anyway?

The point is to get the piston to seat and to get any particles of "stuff" flushed out.

Normally, the ABC engines will be really tight. The fit is not based on rings, but based on the clearance between the piston and the cylinder walls, which in a new engine is pretty tight. Running a few tanks of fuel through the engine will allow the piston and cylinder walls to properly seat or match to each other which will give you optimum performance.

As I said, the best situation is for you to do it on the ground, but there is nothing saying that you cannot do it in the air, just that you can't expect full and optimal performance out of the engine until the piston seats in and when the engine is properly "run-in", which could be from two or three tanks to as much as a couple of gallons of fuel for some engines.

Most sport engines that "we" use (we being beginners, not advanced competition pilots) will be just fine with just about any run-in process. I always profess that one should NOT baby these engines. Get them in the air and fly them. Not many will notice any differences between a bench type break-in and one done in the air. Again, some engines require specific run-in processes, but most of those that we "sport" flyers use, won't.

CGr.

Great thanks, I'll break it in on the ground as the book says just for good measure. Thanks for the info.

The point is, I wasted a minute of my life reading your nonsense assuming at first it was valid fact.

So yeah, I'll keep posting and I strongly suggest CGR you avoid and don't read my posts.

Hey Gray Beard, so tell us - have you ever shot at a kid with a Daisy BB gun?

someone needs to get a life</p>

Someone needs to mind their own business.

In all the nonsense written on this thread I haven't seen any sensible advice - if there was good advice I didn't see it.

To the OP, Bottom line - unless a cylinder is scored (scratches vertically in the cylinder) and if the engine doesn&rsquo;t have too many flights on it (let&rsquo;s say less than 200) it doesn&rsquo;t need to be honed.

People are confused about what really happens when you break in an engine. The process is the same with a car engine or a model airplane engine.

A new or rebuilt engine cylinder is honed to create peaks and valleys. The valleys are where the oil stays to lubricate. You want the valleys. A new ring wears down the peaks.

Modern engines with modern factory tooling require less &ldquo;Break in&rdquo; than ever before.

duplicate post

Edited to add - a prior post I wrote was deleted.

RCU is known to be a stand up forum. I wrote an innocent post, a moderator deleted it.

The ownership of RCU should have a look at who is moderating this forum.

Just maybe to help out a bit... I recently changed a ring on an O.S.61SF, and broke it. It moved off the key tab of the piston when I tried to reinstall it into the sleeve, and the result was two pieces in my hand. I figured no problem, went on the Tower web page and discovered I had to cough up $27 to get a new ring, shipping included ($5). Ouch! You can be sure I'll be careful next time, and would recommend the same to you. Be sure the ring stays on the key in the piston if there is a key.

A second 61SF I have has a frozen ring. I've soaked it in acetone and mystery oil. Heat, cold, both, no luck. Any ideas guys?

Regarding break-in, just running a bit rich should do the trick along with varying the throttle while flying. These are O.S. engines... the reason we pay a premium is because the tolerances are what they are. These are my opinions by the way, and are only opinions. Don't try to confuse me with your opinions, or worse, the facts.

By stuck are you saying it is stuck in the ring groove of the piston or the piston and ring are stuck in the cylinder?? If it's stuck in just the piston and the piston is in your hand just drop everything in Liquid Wrench for a few days then use heat. If the piston/ring are stuck inside the engine and you can't remove it then {this will sound silly} put some Olive Oil in the cylinder and heat the engine up to about 400 degrees in the oven for a while. Pull it out and get a prop tightened onto the crank and chuck up the engine in a vise then try turning it over.