Nitro Engine Break In

[BigBoi87]

I'm buying a new .18RE engine for my XXX-NT, and need to know how to break it in. My friend broke the engine that came on car, so I only have a small idea how to do it.
What is the best way to break in a nitro engine????

 

[Chrizzy]

2 tanks on high idle, 3-4th with 1/4 throttle and makin 8ths, 5th short runs with full throttle.. fine tune and bashin it

 

[alpinehyperlite]

https://www.rcnitrotalk.com/forum/showthread.php?t=68224


The first procedure is called "heat cycling", this is the most important part of break-in and almost no one does it. Start the engine and let it idle, after 1-2 minutes feel the cylinder head, you want it to be hot enough so you can't grab on to it for more than 10 seconds at the base of the head. Stop the engine, make sure the piston is at the bottom of the stroke, let it completely cool down, back to stone cold. Repeat this process at least 10 times !!! I usually dedicate the first tank of fuel to this process. It's going to take some time to do this so be patient.

Now you can take it out and run it. Open the main needle one full turn. The next 4 tanks, run at no more than 1/2 throttle and vary the speed up and down. Let it completely cool down between runs and always make sure the piston is at the bottom of the stroke while it is cooling. Try to run the engine in the 200 degree range during this period.

Now 4 more tanks running up to 3/4 throttle, run it in the same manner as before.

Now you can go wide open, make sure to run it on the rich side for another 6 tanks. Don't try to grab a lot of ponies yet. ( this is easier said than done !!)

Now you can let it rip. These engines run best at temps 220 to 240 degrees. There should always be a VISIBLE line of smoke coming from the exhaust stinger.

Good luck with your break-in. Take your time and do it right and you will be rewarded with an engine that runs stronger and lasts longer than you have ever seen.

 

[BigBoi87]

Alpinehyperlite, Open the main needle one full turn? I'm new to this, main needle is that the high speed or the low speed needle and open is that lean or rich?

 

[alpinehyperlite]

When you open it, you are letting in more air so that leans it out. When you close it, you are constricting the air flow, so that allows more fuel with less air, thus richening it. The "main" is the HSN.

 

[-Goat-]

When you open it, you are letting in more air so that leans it out. When you close it, you are constricting the air flow, so that allows more fuel with less air, thus richening it. The "main" is the HSN.

Aren't those needles for fuel mixture, not air mixture? Needles turned in reduce the amount of fuel flow, not air flow....just sayin.


-Goat-

 

[mrbones]

Aren't those needles for fuel mixture, not air mixture? Needles turned in reduce the amount of fuel flow, not air flow....just sayin.


-Goat-

Yes they are. I'm a little confused after reading that too. You need to do a google search for nitro engine heat cycle break in and read it. Here's one that I copied.

From the very 1st time you start your engine, plop the car on the ground & begin running it in a parking lot in 2-3 minute intervals, tuned only *slightly rich* getting the temps up in the 200F range on a normal day. Every 2-3 minutes, shut the engine down & let it cool completely with the piston at BDC, and then fire it back up; continue this cycle until you've run 15 min or so, and then bump up to 3-4 minute intervals. Vary the RPM and don't be afraid to get the temps in the 200's. What you want is heat cycling of the components without the incredible stress that comes with breaking an engine in when it's overly rich & cold. After cycling the engine in this mannerfor about 20-25 total minutes, it'll be ready for the track and race tuning.

It is also posted at the top of the engine section of this forum.

 

[REVO-5309]

Alpines method is right, but turning needles clock wise will reduce the fuel leaning the motor out (which is bad for break in but sometimes needed to get it moving as from factory and ur location it may be way to rich)

Turning the needle anti clockwise will richen, always go richer before leaner when tuning, once too rich then start leaning out again till the tune is making the most power and in the temp range u want.

 

[alpinehyperlite]

My mistake. Havent run Nitro in several years.

 

[SchrodeMode]

Alpine had the idea correct, just the direction of the turn was wrong.