[Chris]

First of all you really don't want to "BREAK-IN" an ABC engine in the classic sense. An “ABC” type engine (Aluminum, Brass, Chrome) does not require prolonged break-in periods. However, we do recommend that you run the engine at a slightly rich needle valve setting for the first two runs. These runs should be made with the engine installed and running for not less than five (5) minutes periods. Typically an engine will be ready for continuous full throttle and a leaner needle valve setting after ten (10) to fifteen (15) minutes of running.

ABC engines are designed to run at operating temperatures, NOT COOLER temperatures.RUNNING THE ENGINE TOO RICH WILL RUIN THE FIT. If the operating temperature is not reached, the piston is prematurely worn from lack of clearance. You do not want to "break-in" an ABC engine at a very rich setting. Just a slightly rich setting for the first 30 to 45 minutes of running is adequate.



A model engine makes sounds that will tell you how it's performing. You'll have to listen very carefully for them, recognize their message, and make adjustments to the fuel control needle valves accordingly. The mixture of fuel and air is controlled by the amount of fuel metered by the needle valve.

SLOPPY RICH MIXTURE running is characterized by a very slow, irregular, sputtering exhaust sound. The exhaust gas will be very smoky and contain many droplets of oil. NEVER RUN AN ABC ENGINE AT THIS SETTING. The cylinder is not able to heat properly and the fit will be ruined in a short time.

RICH MIXTURE running is characterized by a slower, sometimes irregular, sputtering exhaust sound. The exhaust gas will be smoky and probably contain small droplets of oil. NEVER RUN AN ABC ENGINE AT THIS SETTING. The cylinder is not able to heat properly and the fit will be ruined in a short time.

FOUR CYCLING or SLIGHTLY RICH running is a rich type setting, but it is fast enough to pull the airplane. This is the setting you normally look for before launching the airplane because the engine will run leaner when airborne.

PEAKED OR TWO CYCLE. As the main needle is closed (clockwise), it reduces the amount of fuel mixed with the air drawn into the engine. At a specific point, which varies with each engine, air temperature, altitude and relative humidity, the exhaust note will change quickly into a smooth, powerful note. If the needle is closed further, the note will stay smooth, but will weaken. The peak occurs just at the break point from a rich setting and further leaning will ruin the engine. A lean setting raises the engine heat above the safe point, reduces lubrication, and destroys glow plugs due to high combustion temperature. This is very harmful to the engine and your investment. Learn to tune the engine before running. Remember, a little rich is always preferred for long motor life.

--------------------------------------------------------------------------------

BENCH BREAK-IN
NOTE THAT THE ENGINE MUST BE FIRMLY MOUNTED ON A SOLID TEST STAND OR BOAT. DO NOT CLAMP ENGINE IN A VISE.

The initial bench break-in period is approximately 15 minutes. During this time, use the recommended break-in propeller and run the engine at a slightly rich setting. It is best to run the engine for a full 10 minutes, then allow it to cool. Heating and cooling is not beneficial to an ABC engine as you want it to run at operating temperatures, not cooler temps.

1) Start the engine and run it at a rich full throttle for about 2 minutes, then let it fast idle (about 3500 rpm's) for 30 seconds. Repeat this sequence for about 10 minutes of running time.

2) Increase the full open throttle time to about 3 minutes followed by a 30 second idling period. Do this for an additional for 20 minutes.

3) Install the engine on your boat using an normal size prop.


As aways, consult the engines owner manual for the mfg's suggestion break-in procedure.
_________________
We are saved by Grace....but kept by obedience.