OS32 Main needle setting help

Hey all, i just installed an OS32 pull start in my shuttle, and was
breaking it in yesterday. Just wanted to check if this is normal. The
initial setting is 1.5 turns out for the main needle, but i could not
get the heli to fly right or the engine to run well unless i leaned it
out to about 3/4 of a turn, and now afte ra couple tanks of gas i'm
running it at about 1/2 turn out! It can go probably a bit leaner...

1/2 a turn seems like very little to me. I know every engine is
differnt, but in my years with nitro engines i've never seen one
requireing so little opening on the main needle....anyone else have
this experiance?

thanks
jason

[rotorz]

Hi
My OS50 is about the same and this is very different to my older OS so I assumed it to be the new carboration. Now 8 tanks full through it and it runs lean and cool, and does not miss a beat.

Happy Landings

two things to look at- altitude and smoke.

different altitudes dictate different than normal settings.

The smoke thing is REALLY important. The engine should generate a good amount of smoke when running properly. If there is not smoke you're too lean.

On my OS 32 one click of the knob can make a huge operational difference. Half a turn is huge.

How does it run at 1.5 turns out? Smokey? No smoke? Stead? Sound like its not smooth?

Also make sure you have a few glow plugs on hand. When breaking an engine in on rich needles you'll go through more plugs than normal.

Let me know more about how things sound and how the smoke looks.

JHP, thanks for the info. This past weekend i went back to the field and set it back to 1.5 turns. The engine starts and idles fine, but as soon as i give it some power it start sputtering and eventually dies. I leaned it out slowly, and it started gaining power, eventually got to about 5/8" turn out from closed, and it is again running very well. There is good smoke, i tried the spit test on the cooling head, and it sizzled off in about 3-4 seconds, after hovering almost a full tank, and some flying around...

I think this engine just likes it at about 1/2 turn!

jason

If its smoking good and running strong I wouldn't worry about where the needle is.

The smoke is the best indicator of lean or rich.

If you foul your glow plugs quickly (3-4 tanks) it may still be too rich.

Sounds like you got it. Every engine is different. Keep your eye on it as it breaks in. It may need a few clicks in either direction.

I had this same problem. The problem wasn't the needle valve the problem was the fuel mixture. Take a look down the carb and then look at what it should look like in the manual. Mine wasn't even close, I was pouring way too much fuel through the engine and that is why the needle setting is so low (I.E. 1.2 a turn).

Well, its really hard to look down teh carb of an OS in a shuttle, and my engine is running well, so i don't think i wanna screw with it...thanks tho..

jason

If you have the needle valve only a 1/2 of a turn or so and it should be more like 1 1/2 like yours I would ask some people for their opinion. My opinion (it's only an opinion!) is it's not right and you should fix it. When I got my engine to appear to "run well" with the needle in at aboyt 1/2 a turn I was going through lots of fuel, it was near pouring out the muffler. Turning the needle valve in was a bandaid for me. Again, I am not telling you what to do and I am only offering an opinion.

Here is what I SUGGEST. If you cannot see down the carb with it installed remove it. There are two screws one one either side of the carb. Look on page 12 of your owners manual. When you look down the carb that is what it should look like. I have attched a picture from the manual.