Originally posted by TEAMERICA
I haven't had the screw break off, but I am having trouble getting a good linear mixture. According to the instructions, you should tune the low speed screw according to how the engine throttles up through midrange. Mine goes very rich just above Idle and just below a hover speed. But Idle is Lean!?
I have the screw turned all the way clockwise that it will go and the idle is uncomfortably lean but when I throttle up to hover it goes slobbering rich and sometimes quits. Occasionally I can nurse it and the blade speed will pick up and I can hover comfortably and even FFF and loops. Then, occasionally it will go into that "fat" condition (usually after throttling back and back up after a loop) and I am in a panic descent with low rotor speed and no power cause it sounds very rich.
I am about to flatten this engine on the nearest railroad tracks and put a TT 50 in it.
I have been flying glow engines for over 40 years but this one has me baffled.
Any suggestions?
I fought with this problem when I tried some fuel that the engine DID NOT LIKE AT ALL!! I switched back to CP and havn't had a problem since. I love the OS 50 engine but the type of fuel makes a HUGE difference. I have a fuel pump on mine now and now the mixture stays constant the whole tank, very nice! My OS 50 HATES Power Master and Magnum fuel.
I was out flying my heli the other day (in between crashes) when I started having trouble starting it, no matter how rich I ran the needles it just kept running lean at low end! Mid end was fine but top end was a little low on power. I had a LOT of trouble starting, also. I thought my plug was bad but when I was looking at the engine to check the glow plug extension I noticed the line that runs from the crank case to the fuel pump was broken!!! I couldn't belive my engine was running with a HOLE in the CRANK CASE!! I was shocked!!! I really like this engine a lot!
TEAMERICA
What kind of fuel are you using?
What kind of plug?
Unless you have a really old one the OS 50SX-H does not have a low end needle, it has one of those strange limiters that only move about 260 degrees. Another thing with my OS 50 is that the pinch test does not work with the idle. I set my engine to idle rough then richen it a bit so that it stops popping all together and then hover it. If I land and it pops I richen it up, if my idle is bad I lean it up. The highend I just play with till my engine stays cool after some high power pull outs. I wish my airplane engines were this sure to set up, I have been having trouble lately with my plane engines because I've let them set so long, I lost the nack!