BREAK-IN/RUN-IN OF THUNDER TIGER PRO 50HR ENGINE
It was on Sunday morning with a slight breeze and sunny.I bring out my Titan Raptor 50 into the field near my house and start fuelling the empty tank with my favourite pink 15% Omega Morgan Fuel. Checked the TX, RX and glow starter battery were fully charged. I did the pre flight check and range check. Everythings were alright. My chest was pounding and I was asking myself whether I can make the TT Pro 50 HR alived.! Since the carburetor has been pre-set at the factory, so I did not adjust the Mixture Metering Screw . I opened the main Needle Valve 3 turns out from closed position and closed it back 1/2 turn which was 2 1/2 turns opened.. With OS #8 glow plug installed, primmed the fuel and inserted the glow starter. I ensured the TX stick fully down, throttle trim at neutral, inserted the hex starter….. I pressed the starter switch and ….. I was very surprised to hear the TT Pro 50 HR was alived less than 2 seconds after the starter spinned! A lot of oil and smoke started to come out from the muffler. It sounded like the engine RPM was getting low and hesitating, I quickly set theTX Throttle lever and the Throttle Trim Lever to slightly high to increase the rpm without engaging the cluth. It showed that the engine was run in rich condition and I don’t worry of overheating it.
Away about 15 feet from my raptor, I slightly increase the throttle and at about 60% of my throttle stick and about 1325 rpm, she was lighted on the skid and start hovering and shaking ( rpm may defer depending on your pitch/throttle set-up, rotor blade tracking and percentage of fuel used). TheThunder Tiger wooden rotor blades were out of tracked. Landed and do some adjustments, I hover it again, now the rpm increasing slightly at 1420 ++ rpm! ….. More and more smoke plus oil came out of the muffler and I guess the needle valve setting was just right for this moment. I reduced the rpm and it started to land safely. Observed the rpm and keep the rpm slightly over idle just to keep the engine from quit. At this needle valve setting I still can hear the 4 stroke sound from TT Pro 50 HR. I closed the needle valve 3 notches, still observed the smoke. I hover and land, hover and land again for several times. I looked at the fuel tank, it was 20% of fuel left….! It’s because it ran in rich condition. I hover until the fuel tank empty but my header still tank full. I stopped the engine. I touched the engine backplate that I still can touched it more than 8 seconds.
While waiting the engine to cool down, I inspected all parts to ensure not loose, tightened the muffler hex socket screws to ensure no leaks. I wiped cleaned some oil at the skids,tail boom, tail rotor servo and some other parts of the body with towels and let TT Pro 50 HR coolled for a few minutes.
Checking the RX battery, it was still safe to fly for another a full tank. After 3 tanks of hovering I started closing in the needle valve another 3 notches and I noticed the engine rpm increasing slightly while observing the smoke. I also do the pinched and released the carburetor inlet silicon tube just to ensure the Mixture Metering Screw was set properly.At 1540++ rpm, I almost get the needle valve setting right at a safe and rich side! The needle valve opening now about 2 turns opened.
I do some figure eights, stall turns and the engine still happy with this setting. I fly at this settings for 6 tanks and continue leaning out the needle valve. After 6 tanks of flying, the needle valve opening was now about 1 1/2 turns plus another 3 notches opened and still slightly rich. I opened out the Mixture Metering Screw about 3 degrees for smooth throttle respond at low/mid throttle. Remember do the pinched and released the fuel tubing into the carb. Ensure the engine increased in RPM slightly-then your l idle was correct. If the engine dies without increased in RPM, open slightly the Mixture Metering Screw.
Thunder Tiger PRO 50HR Engine runs smoothly and easy to adjust. I am very happy and glad purchasing and owning this high quality engine. I am flying a gallon now with stall turns, loops and rolls…… Happy flying.
Additional infos of my flying site:
15 ft above sea level
temp: 33 degress
Humidity: about 66%
*NOTE: NEEDLE VALVE OPENING MAY VARIES DEPENDING ON FUEL, ALTITUDES, HUMIDITY AND TEMPERATURE OF YOUR FLYING SITES!