Well my friends, it seems You Tube is being exceedingly uncooperative this evening. So, I will continue to attempt to upload the post 212 repair videos, however in the meantime I will fill in some blanks ya'll are wondering about. My purpose for including you all in this information is that I hope I am able to help others that may be having some issues as well as information that others can refer back to should they need it. All these tests were done with the same prop I bolted on the 212 right from the beginning. Falcon 33x11w.
Prior to sending the 212 in, I set the idle around 1100 rpm. Or there abouts. The top rpm was 5710 during the testing. I'm pretty sure it came up after it was dialed in. When brought up to full power, it was almost like you could hear a rattle and stumble or miss similar to a "rev limiter" on a motorcycle. This is the "something just not right" sound I was referring to. Though I put four really good 11 minute flights on it prior to sending it to AI, I just didn't like what I found as explained earlier. An untrained ear probably would have missed it though it did run good. True testament to the quality of 3w in my opinion.
So fast forward, The first test run since coming back from AI, it came straight out of the box and bolted immediately back on the Yak. Nothing was altered, nothing changed. No needle adjustment, no timing change from what Gerhard had the 3w sensors set at. The only alteration was the removal of the throttle arm from the servo and swung around 180 degrees to accommodate the now correctly positioned carbs. I didn't even have to change the direction of rotation. So with the 3w ignition modules resting atop the RC Excl, (Did not remove them when the engine was sent in) 15 flips with both chokes on, "bark", 5 flips with chokes off...purring like a kitten. idle rpm was a solid 1190 rpm. Now the slight increase could have been from the repositioning of the throttle arm and resetting the trim and epa, so I don't even consider that a valid variable to count on. What I did notice however was the full throttle rpm jumped a full 100 rpm. 5810 at mashed gas pedal. The transition was very good and the 212 ran like a swiss clock.
Next step was to remove the 3w ignition and bolt into place the RC Excl sensors to the "EXACT" same location as the 3w sensors as Gerhard had set them at AI prior to sending the engine back to me. I wanted everything to be as exact as possible so that I would have a very solid foundation for referencing differences in data. No carb needle adjustments were made, everything stayed the same. The only difference was the 3w ignition and sensors out, the RC Excl in. Here is where I noticed the same improvement that I have been noticing and stating with my 157cs and my 170. It takes about 15 minutes to remove the "dub" ignition and install the RC Excl. Once this was done, I flipped the prop one (1) time, no choke and that beast roared to life. The idle rpm? Lol, wow...1960 rpm. An instant gain of 750 rpm. Remember, nothing was changed. Ferrari lightening fast throttle response. Transition about the same. So once the idle trim was re-set, I ran her up to full power. Another 50 to 100 rpm. increase over the 3w ignitions. For a total of about 200 plus instant bolt on rpm simply from correcting the crank timing with a new crank and other repairs, as well as the RC Excl igniton. That right there is danged impressive to me. From past experience, a small block 350 chevy or big block 454 will only develop the horse power and rpm it is capable of without major modifications. The same holds true with our RC aircraft engines. But to see this much of an increase was pleasingly shocking.
Something else was extremely pleasing to see. Prior to repairs the temps were all over the board ranging from about 190 to 250 degrees "F" on the cylinders. with the one severely out of time, 280 degrees. This was open air with the cowl removed. No baffling. After the repairs? Right side cylinders, 161 for the front, 163 for the rear. Left side cylinders were 172 for the front and 173 for the rear. As we all know with twins and quads, one side of the engine usually runs a tad less clean and cooler while the other side is slightly warmer and cleaner. A cooler cylinder will be less clean on the exhaust while a slightly warmer cylinder will be much cleaner. Due to a more complete fuel burn. Now the 212 is back to where it should be and well within the norms of a properly tuned engine.
To say I am pleased would be an understatement. I hope to have the baffling completed and the new cowl installed so that I can put her in the air on Tuesday. As soon as I can get the test run videos uploaded, I will post them here so that everyone can see the difference.
My hat is off to Gerhard. There is only one way I could have gained more than what I did and that would have been with a brand new 220 cs.
