[SPKE]

I just got a new novarossi .21 engine for my truggy. Ive read that the best break in procedure for this engine, or any engine is the heat cycle method. But after doing some research on the procedure, Ive been getting to many different variations. A example would be: One site said to let the engine just run on the starter box for one tank of fuel, while another site said to immediately start doing some figure eights, while another site said to go only half throttle right after starting it.

What do you guys think would be the best Heat cycle procedure?

[Admin2]

Following the procedure that the Manufacturer recommends is always your best bet. Not all motors are made from the same materials or metal. Which can affect break in procedure.
Of course you will always have people who do it differently but if you stick with what is recommended more than likely you will have less issues down the road.

[SPKE]

unfortunately the engine does not come with any instructions for break in. Ill look around their website and see if it states anything. I'm sure it must have something.

[rccardude04]

I have always had better luck driving it around gently than letting it idle. Engines that I've let idle seem not to last as long. I think they just don't get enough temperature to break in properly and esesntially just scrape the piston/sleeve together too hard.

I just set the needles to a little richer than race tune and keep the rpm low. Not going to be the only way you'll read to do it, and certainly not everyone will agree that it's the best or even a correct method, but it's worked great for me and every t-maxx/revo/whatever I've broken in for customers at the hobby shop over the last 10 years. The important thing seems to be just to be easy on it and make sure it's NOT LEAN.

-Eric

[SPKE]

The site states: A gas powered engine requires careful running in to allow the internal parts to achieve proper operating clearances.
Enrich the fuel-mixture from factory position by turning the main needle 1/2 turn counter-clockwise.
Run the car up to half-speed (at most) using moderate acceleration.
Do this for 4 - 5 tanks of fuel.
On the next 3 tanks of fuel, slowly increase the speed and acceleration, and start leaning the main needle setting by turning the needle clockwise.

I'm assuming that before every start I should pre heat the engine to 200F and should let the engine cool at BDC? Or just refuel and continue?

[Admin2]

Originally Posted by SPKE

The site states: A gas powered engine requires careful running in to allow the internal parts to achieve proper operating clearances.
Enrich the fuel-mixture from factory position by turning the main needle 1/2 turn counter-clockwise.
Run the car up to half-speed (at most) using moderate acceleration.
Do this for 4 - 5 tanks of fuel.
On the next 3 tanks of fuel, slowly increase the speed and acceleration, and start leaning the main needle setting by turning the needle clockwise.

I'm assuming that before every start I should pre heat the engine to 200F and should let the engine cool at BDC? Or just refuel and continue?

Allow the engine to completely cool between each breakin run. I don't think it's necessary to pre heat the engine prior to starting it unless the temp outside is cold below 50 degrees f or if it doesn't fire up right away. If its below 50 degrees outside it will be near impossible to achieve the proper temps on the engine for a good breakin.
The idea is to get the engine temps up high without over revving it. Then cool then repeat the process.

[SPKE]

Do new engines tend to get hot during break in while the high speed needle is set very rich? If not should I put a sock, or something on the cooling head so it does reach high temps of 200F?

[Admin2]

Originally Posted by SPKE

Do new engines tend to get hot during break in while the high speed needle is set very rich? If not should I put a sock, or something on the cooling head so it does reach high temps of 200F?

You shouldn't have any problem reaching proper temps if the ambient (outside temp) isn't cold. If wind is an issue place the car on something so the wheels spin free and just run it low-mid throttle until it gets hot. Don't place anything on the head as it can overheat very rapidly.

[SPKE]

Originally Posted by LOST IN MN

You shouldn't have any problem reaching proper temps if the ambient (outside temp) isn't cold. If wind is an issue place the car on something so the wheels spin free and just run it low-mid throttle until it gets hot. Don't place anything on the head as it can overheat very rapidly.

Thanks, hopefully everything will go ok. Im surprised that the engine did not come with any break in instructions. My OFNA picco came with full instructions on how to break in the motor, that my old LHS used.

[rccardude04]

I always liked to preheat mine with a heat gun so that it didn't have to run cold. Less cold running = less scraping since the tolerances free up.

Not necessary, but it can't hurt.

-Eric

[Budman_222]

Originally Posted by rccardude04

I always liked to preheat mine with a heat gun so that it didn't have to run cold. Less cold running = less scraping since the tolerances free up.

Not necessary, but it can't hurt.

-Eric

It's a lot harder on the con rod too to start it cold. It's so much easier on the motor in general when it's warmed up for the first few starts.

[rccardude04]

Originally Posted by Budman_222

It's a lot harder on the con rod too to start it cold. It's so much easier on the motor in general when it's warmed up for the first few starts.

Also a good point. Less fatigue on parts if you warm it up force because the stresses are lower.

-Eric