Hello RC fan's,

I would love to have your thoughts on my Break in nitro heath cycle method. Is Wrong or Right? and Why?

It is my 1st experiente with a .21 Nitro Engine, using an Alpha Lutz a872 (specs) with original pipe, and fuel Byron 25%.
It was really hard to get the first start!! After help of 2 friends, we had to remove plug and put wd40 in it, then heath it up at 100C and make the engine turn few times. It seems no starter box was strong enough to make it spin, we used 3 different ones... But finally it did spin a bit, then I put a new plug.

Covered engine with aluminum foil heath up with hot air gun to around 100C. First tank ran about half on top of the starter box, the on the ground but barely moving.
Let it cool down to about 45C, then heath up and ran it on the ground doing 8s circles and slowly pushing it never more then 3-4 seconds. 3rd and 4th tank about the same, but i did let it cool down
5th and 6th tank no heathing, lean a bit and laped on track it was a amazing powerfull only half of throttle max temp was about 120C

7th tank on vídeo https://youtu.be/9TU3wGx3ppk

There are many different break in methods...and people just tend to stick to the way that they have always done it..."if it aint broke dont fix it".

A couple of things that I do are...
Feel the pinch- how tight the engine is to turn over....when it is warm you will notice that it becomes easier to turn over as you run more fuel through it...this can give an indication of when you can start running harder/leaning the mixture.
Also I mark the flywheel with a marker pen or a scratch so that I have a visual reference of where BDC (bottom dead centre (piston position)) is and always line up the mark when I stop the engine.

Heating the engine is a good thing to do...not only when the engine is new but for every cold start...when the engine is cold then the pinch is tight, warming it helps to relieve stress/wear and will make it last longer.

Thank you for the review.

I am kind of new to feel the pinch, but I did notice when it was new how hard it was to turn it! Man it was really tight!
I am afraid of leaning it too much, I heard its bad for the engine no? I have it little rich now, guess I will lean a bit.
I wish I could always carry my heath gun with me, but that is not the case. At least when I first start it up I wait about 1-2m on the bench before putting it down and starting racing the car.

Getting the engine heated up as quickly as possible is important. When starting the engine cold, get it running so it will run without the glow driver by driving it around. I usually throttle it a bit and run a few straights. If it cuts out at all while warming up, it's too lean and needs to be richened up a bit. If it's winding up slowly and real smokey, lean it down a little bit and do a few more straights wide open throttle. If it's too rich, it won't warm up enough to get to normal operating temp. I always start rich and work leaner running WOT passes in between adjustments to determine if it needs more adjustment. I will lean it down until stops stuttering rich on the top end. If it revs up and keeps revving up cleanly with no stuttering, then the high speed needle is set to peak. Once at peak, it's always a good idea to back it off rich about 1/16th turn. Set the idle needle so it can idle for about 15-20 seconds and throttle up cleanly. If after that 15-20 seconds it quits when you punch the throttle, it's still too rich.

When it comes to break-in, I'm not a believer of idling the engine for any amount of time. They don't get hot enough which causes more problems and doesn't really allow the parts to bed in properly. The parts that are the most important to seat during break-in is the connecting rod bushings. These bushings seat when run at rpm under normal loads. The piston/liner take care of themselves during break-in as long as the engine is run at operating temp. Fire it up, run it rich for a little while driving the truck, then lean it down to peak and back off rich 1/8 turn so when run WOT it stutters a little at the top of the rpm range. Lean the idle needle down so it idles nice and revs up cleanly. If it starts to get too warm, run a WOT pass (which should be more rich than normal running) which should cool it off.

Nothing magical about it. Fire it up, get it warm, and run the dickens out of it. No need to baby it or run it way rich. As long as the engine is warm, you're safe. Don't get caught up with tuning the engine to run at any specific temperature - if you do you'll just be wasting power (fuel) and possibly causing extra stress on the engine. I rarely check the temp of my engines - if they are running right, they're at the right temp. Checking the temp for reference isn't a bad idea for novices, but use that for reference only. Just my $.02

Learning to read your glow plugs will help you learn to tune. Attached (hopefully they upload in the proper order) are several photos of glow plugs. They should appear as "too rich" (bottom of plug looks brand new), "just right" (nice gold color), "too lean" (bottom of plug is black, element may appear fuzzy or have a dull gray appearance), and "WAY too lean" (element crumpled, distorted, or broken element. Bottom of plug black with small pits). A gold color on the plug base and a shiny silver element is good. A slight grayish element and gold plug base means you're at peak mixture. Go no leaner than this setting.

As for heating the engine...there are many other ways. I guess you are using a starter box because of the engine you have...so you have battery power.

Cheap as chips way is to put a car headlamp bulb in a bean tin or similar that will fit over the head of the engine...of course be aware that the tin will get very hot.
A more professional looking thing can be bought it is called "RC Sure Start" it uses the same principle of the bulb to provide heat but is insulated.
Or there are the wrap around type of warmers that use the same technology as tyre warmers....I have one of these that are very well priced in the UK- http://www.modelsport.co.uk/index.ph...FQQXwwod0n4F5A

Good pictures there Tim...I may borrow them when needed ...just the other day I was explaining how to read the plug on another forum and I tried to take some pictures to assist (pictures worth a thousand words)....but my camera is just not up to the task.

No problem, Ant. I'll take some clearer pictures and repost. The ones I posted are a little fuzzy due to using my phone instead of my digital camera. But one should get a good enough idea from them anyhow. I have a few other plugs somewhere with really crumpled and mushed elements from a lean run. Over-compressed engines will just compress the element usually leaving the element round, just pushed way into the plug cavity. I'll see if I can find those plugs and get some photos of them as well.

Thanks guys.
I will keep in a eye in my glow plug. As soon as I get home.
I ran about 1 gallon in the engine, and my breaking method seems very effective so far.
The engine is very very strong! I can never pull full throthle in it, must is about half.
Should I use a smaller Venturi intake ? I think I have an 8mm but it came with other 2 sets.
Will I have to mess with the needles?
Tested the flashpoint nitro 25%, quite nice, but noticed less smoke is it normal?

cheers

If you change the venturi then yes you should adjust the needles...also change the end point adjustment of the servo....personally I always use the largest venturi- using the smaller venturi can improve economy and low end response/power.

I have never used Flash Point fuel and there is not much information available on the internet from what I can see....but I think it is made/mixed by VP....and I have used VP and that was 9% oil and relatively smoke free.....but of course remember that if you are changing from one type/brand of fuel to another then you should retune.

Thanks, for the info. Maybe I will try the 7mm venturi.
Does anyone know a good link for cleaning and maintaining a nitro .21 engine?

I noticied my glowplug was black! Guess I was too lean.

Also my clutchbell is getting stuck, I will buy a new one this week.