which break in procedure to follow?

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FRIDGE

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I just got my XTM.18 engine for my rs4 and read the instructions and for break in it said to just start the engine and run it rich for 2-3 mins then let it cool for 10 then do it all over again. this sint the break in procedure I'm used to I'm used to the 3 heat cycle tanks then run. which procedure should i follow?
 
On my brother x-cellerator We followed xtm instrustion and have 3 gallons threw it in about a month! and it stills has great compression ! I really like the motor and might put it in my gf ntc3 !
 
Here's what I did for mine, let the engine cool completely between tanks, always stop engine at bottom dead center! I didn't use the heat cycle method, but I didn't use xtm's method either. Also I think I fouled a glow plug halfway through my break-in, so if it suddenly won't start, try that.
first tank, idle through whole thing, stop engine after 5 minutes or so (before tank is dry), let cool at bottom dead center (BDC)
2nd tank, repeat
3rd tank - lean slightly and putter around - less than 1/2 throttle let cool at BDC
4th tank - drive around short bursts to full throttle and back down - let cool at BDC
5th tank - lean some more and drive normally - let cool at BDC
6th tank - lean a little more and repeat number 5
7th tank - should still be running slightly rich, but pretty close to optimal richness, almost done.
beyond 7th tank... now start tuning it.
You can repeat number 3 and/or number 4 to be safe, try to keep your temps under 220, preferably under 200. I've got just under a gallon through mine, still running good. I only get to run once a week or so though.
 
There are several different methods for break in, but do EXACTLY what the manual recommends for that specific engine.
Before you start it, set the piston at BDC (full down) and put a mark on top of the flywheel. As soon as you turn the engine off, move the flywheel till that mark is at the top. It needs to cool down without the piston being up in the sleeve.
Take your time and do it right. Don't get bored or impatient with it. The payoff is a good running, reliable engine with long life.
 
7-8 tanks of fuel would be my break-in preference in 1/2 tank intervals letting it cool down with the piston at bottom dead center in between 1/2 tanks. I would not run it at wot for even short bursts beforehand keeping your temps in the 200-220 range. Do not run it to cold during the procedure or you may end up with an improper break-in as in not broken in.
 
I have tried and also witnessed various ways of breaking in an engine.
For my OS engine's, I idled 4 tanks, did lazy circles (1/4 throttle) for 3 tanks (1/2 throttle for 3 tanks) then started leaning out the engine till I got the performance I liked (check for temps regularly) over 4 tanks. Once that was done ... I changed out the plug, set the needles to factory and retuned for performance.

For my Novarossi NS12S3A1 and Mugen-Seki X12, I idled 1 tank for initial honing then I ran it in at 1/4 throttle for 3 tanks. Afterwards I ran it at 1/2 throttle for 6 tanks, leaning it out 1/4 turns after every tank after the third tank at 1/2 throttle.

My Thunger tiger 21 R on my schumacher, I ran it in from the first tank (schumacher's instructions) at 1/4 throttle for 3 tanks 1/2 throttle for 6 tanks then started leaning it out from there till I reached 230 degrees. Afterwards I reset needles to factory and tuned for performance.

My brother's RB V12, Nitrostar 25 and Mugen-Seki were done via heat cycle.

My cousin idled his TOP TSR12S3 for 7 tanks, 1/2 throttle for 4 and then tuned for performance.

All these are good proceedures. The most important thing for these engines is to get them to operating temp (180-200) for proper honing of the piston and sleeve. Don't over heat it and take it easy since the engine is still tight.

Here is an article I came across from Wildhobbies.com

Nitro Motor Break-In Basics

Topic: R/C Cars
Category: Tips
ArticleID: 1054
Date: 10/13/2003 8:01:00 PM
Written By: WildHobbies

There are are more methods of breaking in a new nitro motor than there is motor manufacturers. Every nitro motor manual says something different, and every place you go, you will hear several other methods being used. Basically, no matter which method you hear described, it will break down into one of three categories:

High RPM break-in,Gradual leaning of the motor settingsHeat cycling
For each one of these, you will hear people how great it is and how much longer a motor will last using each method. I will briefly describe each one.

High RPM Break-In
This is one that has been heard more and more lately. The simple concept is that you run the motor at as high of an RPM as possible and burn through a full gallon of fuel. During the process you keep an eye on the temperature and try to maintain between 190-200 degrees. If you are tempted to try this, be forewarned, this should ONLY be attempted by very advanced users. It is very easy to not pay attention and have the motor cook itself before you ever get a chance to run it. this particular method has been recommended to me by several pro drivers. My concern is that those same pro drivers get their motors for free or deeply discounted so while you may get the performance out of the motor, lifetime is potentially decreased.

Gradual Leaning of Motor Settings
This is the process recommended in virtually all manufacturer manuals. The basic concept is that you start with settings that are as rich as the motor will fire up and run on. Let the motor idle through two tanks of fuel keeping an eye on the temperature to make sure it isn't getting too warm. After the initial two tanks, stop the motor and make sure the piston is at the bottom of the stroke and let it cool off.

Next, top off the tank and adjust the high speed needle 1/8 of a turn clockwise (leaner) and after every tank or so, lean out the needle another 1/8 of a turn. Most manufacturers will recommend letting the motor cool down between tanks. After 3 - 6 tanks (depending on which manual you read) you continue to lean the settings 1/8 of a turn at a time while also allowing the motor to run at slightly higher RPMs with each tank.
This method is recommended by motor manufacturers because it will get you started and running in a relatively safe zone. The more stretched out you make this process, the better your results.


Heat Cycling
Heat Cycling is the most time consuming break-in process but what is sacrifices in time, it makes up for in performance and lifetime. Heat Cycling is the preferred method of break-in used by many of the top motor builders. The point of heat cycling is to warm up the motor, let it cool down, and repeat. The exact procedure as recommended by Nitro Dan of Affordable Nitro Tech Racing is as follows:
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. It should still be running somewhat rich at this point.

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


Click here for article
 
Last edited:
Diver6127 said:
Heat Cycling
Heat Cycling is the most time consuming break-in process but what is sacrifices in time, it makes up for in performance and lifetime. Heat Cycling is the preferred method of break-in used by many of the top motor builders. The point of heat cycling is to warm up the motor, let it cool down, and repeat. The exact procedure as recommended by Nitro Dan of Affordable Nitro Tech Racing is as follows:
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. It should still be running somewhat rich at this point.

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
This is kind of like what I posted. This is from the link I posted:
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 manner for about
20-25 total minutes, it'll be ready for the track and race tuning.
 
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