Calvinman

Well, I ran up the 46 tonight, put 2 tanks through it.Is this enough for a good break in of the new ring? I am just making up a motor mount for the 50 to put it in my Tiger 2 to run it up.

Calvi

1QwkSport2.5r

I usually bench run a ringed engine for 45-60 minutes at WOT. In that time the ring is about half-3/4 seated. You need to run them very rich for awhile because the ring not being seated won't transfer heat well and as such your engine will run warmer.

If the engine will idle for a reasonable time, transition okay, and hold a good (rich) WOT setting, you could fly it. Be aware that engines with unseated rings can be a bit fickle. Be prepared for dead sticks just in case.

Calvinman

Hi 1Qwksport, It is idling nicely with smooth transition, I can hand start it usually first flip, I have been running it rich, but going lean for a second then back to rich, should I just let it run rich when breaking it in?

Calvi

blw

My Feedback: (3)

See how it runs leaned out some more. Maybe it is ready to go flying?

Calvinman

I think I had better put a few more tanks through it to be sure. I will be putting it in my Crusader 11 pusher style and I don't think I want a flame out on the maiden.

Calvi

Calvinman

Running the 50 tonight, I am going to put some more fuel through the 46 at a later date. Had to use the electric starter on the 50, I could get it to fire flipping with the chicken stick, just too many flips for one little bump, then flip, flip flip again. Starts right away with the electric starter. I am running it super rich and it seems I have to keep leaning it up just a tad to keep it running, not sure if this is normal or not, but I have run it for two or three minutes the first run, then 5 minutes the last run. the enginweuld start to sag so i would back the throttle off and it would run great at half throttle, I leaned it up a few clicks and it would run WOT again.

Calvinman

Well the 50 is being cranky! it would not run WOT for more than a few minutes then start to sag, it is plenty rich, sounds like it is 4 stroking to me. I changed the glow plug, a little better, still starts to sag after 2 minutes, so two minute runs it is.

Calvi

Calvinman

Better run that time, I could literally feel and hear it making more power. Ran it for 2 minutes.

Calvinman

Wow, that 50 makes some power! It seems to peak out with the barrel 7/8 open. this maybe because of the wrong carb on it? anyway, I have a bunch of oil to clean off the floor and wall now lol.

Calvi

1QwkSport2.5r

When it starts to sag, it's starting to heat up and lean out. Rather than back the throttle off, richen the needle a half turn to cool it back off. I run my ringed engines as rich as they will run, at WOT, without glow support for two tanks. Then for each tank after, I lean it maybe 500rpm or so each half tank. If at any time it starts to sag, I richen back up 500rpm and let it run another half tank and try again. Ringed engines need to be run at WOT until the ring has a good beat start to seat or they will sag and go lean on you.

My method mimicks that of a lapped iron engine break-in, but I tried running in a ringed engine at the 2/4 break for a half hour and the results were so unimpressive I went back to the way I have had work well in the past.

Calvinman

Maybe I used the wrong term when I said the engine was sagging, it Just seemed to be slowing because it was too rich? I wanted to keep this one rich all the time, like you said, breaking it in at the 2/4 break does not seem to work all that well with the ringed engines. I agree with you, I was not all that impressed doing the 2/4 on the 46, it does not seem much better than when I started the break in.

Any way I will not have time to finish the break in for a couple of weeks, so hopefully I can put 3 more tanks through each engine after that.

Calvi

1QwkSport2.5r

Typically an engine already running rich in a 4-stroke type run won't sag further unless the ring starts to seal better. Usually in the first quart of fuel it isn't sealing well and keeping it extra rich will help keep the ring cool. If you get too lean, the ring will overheat because an unseated ring doesn't transfer heat nearly as well as a seated ring. I haven't had an engine all of the sudden "go rich" and sag/slow down in the early stages of break-in unless the needle moves in its seat. Once you get to the 2/4 break where its occasionally hits a 2-stroke run and goes back to the 4-stroke run, leaving it there for awhile you'll start to hear it firing every stroke more and more which tells you the ring is sealing better.

Hobbsy

My Feedback: (102)

Typically, when an engine's ring begins to seal better the engine accelerates. Most of you have seen my Saito break in method, 4,000 rpm for 10 minutes, 5,000 rpm for 10 minutes etc, during the 5,000 rpm 10 minute period the engines usually accelerate about 500 rpm, throttle locked of course, then during the 6,000 rpm run they only accelerate about 100 rpm. I for one don't subscribe to running the engines sloppy rich because the cylinder runs stone cold and why would you want to set up engine clearances stone cold, they'd end up all wrong. I've broken in about 40 Saitos, several SuperTigres and many Foxes, I've never messed one up.

1QwkSport2.5r

As I understand it, heat transfer is poor to the cylinder walls and crankcase when the ring isn't seated and the richer fuel mixture helps keep it cool. Upon the recommendation of others, I tried running a ringed engine to seat a ring at the 2/4 break for several tanks and gradually leaning after that and the end result wasn't any better than the original ring that came in the engine. That is power production wasn't much if any better. I do use your method to break-in ringed 4-cycles, but ringed 2-cycles I treat differently. I use a smaller prop to run at the desired rpm and still keep the engine rich. This allows the engine to stay well lubricated and still run close or at operating temp. The initial very rich running is mainly to keep the ring cool during the first few runs.

Not being argumentative, just adding a different perspective? I'm not an engineer or designer, so my point of view is really from what I've read other guys do. If there's a better way, I'm always open to try other methods out.

Hobbsy

My Feedback: (102)

Due to the fact that the ring isn't fully seated there is more room for oil and besides our engines, if using factory blended fuel, are way overlubed so running them lean enough to run with out the glow heat will not hurt a thing. I am not an engineer or a scientist either, I just go by my experience. Don't take my experience being different as argufying, a western Pa. term.

Calvinman

Well one things for sure gents is that I should invest in a tach! It is one item that is always at the back of the list of "must haves" there always seems to be something more urgent popping up on the list. I was running a APC 11-6 on both engines. The 50 seemed to be pulling much harder than the 46. It is always nice to get more than one persons way of doing things as long as mayham does not break out

Hobbsy

My Feedback: (102)

Pulling much harder, equals, revving much higher or laboring much harder?

Calvinman

Revving higher

1QwkSport2.5r

Took this the other day. Not much pull from a 7x4, but a whole lotta noise, yes! Sorry, not a .46 or .50... But is an OS anyway.... 21SE (ABN) Marine circa 1985.

blw

My Feedback: (3)

It's easy to get all over the map talking about breaking it engines. First, all engines are different. Rich and sloppy rich are different animals. Saito calls for a sloppy rich period that seems to work and I use it. Dave, I think a lot of people pretty much break their Saitos in the way you're calling your own.

There's are lot of rotating parts that are rubbing and beating each other until mated smoothly. Rings are a small part of the whole process.

Hobbsy

My Feedback: (102)

Tim, that pitcher I showed is of an Irvine .20 Diesel turning a Bolly 10.5x6, the little feller is strong.

Sport_Pilot

Hard to tell. Looks good in the last shot. Good luck replacing that. Might as well put it back even if worn. BTW dykes rings have poor compression when propping over. Typically hot dykes ring engines are hard to start by hand and you will need an electric starter. They expand from the combustion pressure to make their seal. They were very popular with racing engines before ABC came along.

1QwkSport2.5r

That engine must still be breaking in a bit yet; it was new before you ran it wasn't it?

Calvinman

Not sure what it is revving, but pretty sure it is no where near 24,000. I have the fuse teathered on an old wooden table I also hold it back with my hand on the landing gear, feels like it is pulling as well as the RJL 61 that was on it.

CESSNA 421

My Feedback: (17)

If anyone is interested I have a few of these OS50 FSR engine I bought years ago and replaced the rings and bearings in them. I will probably not use them in the foreseeable future so it maybe time to sell them.