Andrew Davies 3 Posted February 22, 2017 Share Posted February 22, 2017 Hi all, After possibly the longest build of an ARTF Seagull Boomerang in history, it's finished and (hopefully) ready to go. I've found a local model club with someone who's prepared to give it a look over and then teach me how to fly it, but in advance, we agreed that it would be a good idea to run the motor for a couple of tanks of fuel. He suggested opening the needle valve two and a half turns, and then alternating between idle and almost full speed to run the motor in. I've managed to start it, but I think it's running rich. It won't rev particularly high (it sounds like it's about to cut out) and it looks like fuel is spitting through the exhaust. What am i doing wrong? I'm assuming that opening the needle is anti clockwise? Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted February 22, 2017 Share Posted February 22, 2017 You are doing nothing wrong Andrew, it is just running rich Turn the needle in, clockwise slowly, with the motor running, until you can throttle properly Then follow your run in routline Edited By Denis Watkins on 22/02/2017 17:31:39 Quote Link to comment Share on other sites More sharing options...
Andrew Davies 3 Posted February 22, 2017 Author Share Posted February 22, 2017 how many turns would you imagine would be right. I read somewhere one and a half? Thanks Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 22, 2017 Share Posted February 22, 2017 Correct, my old flying instructor said," one, one-half and a bit for luck" Quote Link to comment Share on other sites More sharing options...
David Davis Posted February 22, 2017 Share Posted February 22, 2017 You're quite correct Andrew, to weaken the mixture you screw the main needle inwards, i.e, clockwise. The reverse is true to establish a richer setting. A two stroke engine never really runs smoke free, it discharges some oil, smoke and unburnt fuel at even optimum settings. It sounds as if your engine is running rich. Have you tried screwing the main needle in while the engine is running? Which engine do you have and is it new? Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 22, 2017 Share Posted February 22, 2017 If you are running in a non ringed 2 stroke engine. Then follow the manufacturers running in instructions. You need to have cycles of hot and cool cylinder temps to get the gas seal and to let the cylinder and piston " bed in " together. Quote Link to comment Share on other sites More sharing options...
Andrew Davies 3 Posted February 22, 2017 Author Share Posted February 22, 2017 I was just about to try it but realised that the servo battery needs charging - doh! I'll give it a go when it's charged enough to operate the throttle. Its an SC .46 and yes, its straight out of the box Thanks again and sorry for the daft questions Quote Link to comment Share on other sites More sharing options...
Andrew Davies 3 Posted February 22, 2017 Author Share Posted February 22, 2017 Posted by cymaz on 22/02/2017 17:43:07: If you are running in a non ringed 2 stroke engine. Then follow the manufacturers running in instructions. You need to have cycles of hot and cool cylinder temps to get the gas seal and to let the cylinder and piston " bed in " together. the instructions with the engine aren't particularly helpful for a beginner. They talk about 4 stroking and 2 stroking? Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 22, 2017 Share Posted February 22, 2017 No such thing as a daft question.....not on here anyway. Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 22, 2017 Share Posted February 22, 2017 4 stroking is when the 2stroke engine is running rich and quite "lumpy"....f.f.fa..f fa..f.f 2 stroking is when there is a clear continuous high pitch rev at wide open throttle...zzzzzzzzzzzz If that's any help. Which it probably isn't Quote Link to comment Share on other sites More sharing options...
Andrew Davies 3 Posted February 22, 2017 Author Share Posted February 22, 2017 So what I imagine it should sound like....? That's really helpful, thanks Quote Link to comment Share on other sites More sharing options...
Don Fry Posted February 22, 2017 Share Posted February 22, 2017 Patience will get you everywhere. Keep your fingers out of the prop arc. Keep your fingers out of the prop arc. Don't be tempted to get your fingers in the prop arc. Can't go too much wrong thereafter, unless you forget to remember to keep.............. Good luck. Quote Link to comment Share on other sites More sharing options...
Andrew Davies 3 Posted February 22, 2017 Author Share Posted February 22, 2017 you must have seen me earlier... I managed to cut one just rotating the prop while I was priming it. lesson learned! Quote Link to comment Share on other sites More sharing options...
Don Fry Posted February 22, 2017 Share Posted February 22, 2017 No, the lesson has not been........... Sit in your favourite chair, wrapped in rags, wishing to die. And then you will need to remember. Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 22, 2017 Share Posted February 22, 2017 Ouch....go and get a chicken stick, or make your own! The good lord only provided one set of fingers to play with ! Here is an example I was showing some air scouts on how to be respectful of little RC 2 stroke motors. They were all a bit dismissive of my OS 40 la....until I placed a raw sausage on some tongs into the blades. It was only idling and the motor didn't even notice. You could have heard a finger pin drop. Edited By cymaz on 22/02/2017 18:10:06 Quote Link to comment Share on other sites More sharing options...
Andrew Davies 3 Posted February 22, 2017 Author Share Posted February 22, 2017 That's the stupid part, I have a chicken stick!! I just wasn't using it to prime the engine .... Quote Link to comment Share on other sites More sharing options...
cymaz Posted February 22, 2017 Share Posted February 22, 2017 I bet you will now! Quote Link to comment Share on other sites More sharing options...
jrman Posted February 22, 2017 Share Posted February 22, 2017 I presume you are using a glass reinforced nylon prop. If so just rub the leading and trailing edges with sand paper to take off the razor sharp edges. Prevents the type of cut you experienced but it doesn't do anything for the "rotating" cuts! Donald has given you good advice but I don't think he stressed it strongly enough. Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted February 22, 2017 Share Posted February 22, 2017 Every minute running Andrew, is a minute closer to running in And easier starting then And Always start on Idle I bet you had throttle up? Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted February 22, 2017 Share Posted February 22, 2017 Posted by jrman on 22/02/2017 18:11:23: I presume you are using a glass reinforced nylon prop. If so just rub the leading and trailing edges with sand paper to take off the razor sharp edges. Prevents the type of cut you experienced but it doesn't do anything for the "rotating" cuts! Donald has given you good advice but I don't think he stressed it strongly enough. I was just going to say the same thing, remove the moulding flash from the edges of ALL propellers. The Master airscrews are so sharp you can carve balsa with them. I was trying to start a friends engine and cut my finger on the prop. All I will say is that he NEVER forgot to remove the flash again after I "explained " what he had failed to do. Quote Link to comment Share on other sites More sharing options...
Andrew Davies 3 Posted February 22, 2017 Author Share Posted February 22, 2017 Update.. Just started it with one and a half turns and it sounds much more like i expected it to. Will run a couple of tanks through it and cycle between power and idle. Anything else? Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted February 22, 2017 Share Posted February 22, 2017 Stick with that buddy, then it will be ready to fly the Boomerang Quote Link to comment Share on other sites More sharing options...
Don Fry Posted February 22, 2017 Share Posted February 22, 2017 Good electric starters are heaven. I am blessed with a short SWMBO. Six inches cut off a broom has never been noticed. But the starters elbow cost the health service a lot of money. Stick to a good starter. Don't on any account risk any bit of you hitting the prop. Mind, I do not expect any understanding until that soul juddering moment, or in the case of tougher material, two soul juddering moments when the prop bites. You sit there. I got away with that. And then the blood flows. And then the pain. And then the frightening bit, can I get up, drive??? Don't underestimate the ability of a 40 to hurt. In fairness, it will, probably ,just make you one handed, for a few days. Have fun. Edited By Donald Fry on 22/02/2017 21:01:55 Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted February 22, 2017 Share Posted February 22, 2017 Not wanting to scareyoy but back in the 80s or 90s, RCM&E ran a picture of someone. Their Irvine 40, running at full chat had removed 3 fingers. Mind you,he was launching a pusher. Models with props in strange places are very dangerous, had one or two myself and seen a few more accidents.. Now I refuse to even touch a model with the prop anywhere but at the front. Quote Link to comment Share on other sites More sharing options...
Don Fry Posted February 22, 2017 Share Posted February 22, 2017 Peter I agree, a pusher pulls it victim into the maw.. That was the second incident. Quote Link to comment Share on other sites More sharing options...
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