How can I tell if my OS32 is running to lean?

[edm3]

Hi all,

I am another newbe and have a question. So far I have managed 8 flights, all hovers and I fell I am getting better each time. I have heard that running your engine to lean will ruin the engine. So far my OS32 seems to run strong with no starting problems. During hover flight there seems to be plenty of power and a fair amount of smoke. So how do I tell if I am running lean?

I am having a GREAT time with my new hobby, I'm hooked!

Ed Doyle
Paptor 30
Futaba 7chp
Futaba gy-401

[WillJames]

Feel the backplate of your motor with your finger after hovering a bit and see it it is hot. It should be pretty warm to the touch, but definitely not hot enough to burn you.

[blakka_1]

Also you should see a nice trail of smoke coming from your muffler. If there is no trace of smoke, or a very faint trace of smoke coming from your muffler then your engine is probably on the lean side. :)

[edm3]

Thanks for the information. I will give it a try the next time I fly. I am getting a fair amount of smoke so hopefully All is well with the mix.

Ed :)

[marked23]

My thoughts on this:

Temperature:
(You probably have a non-ringed OS32, but check.)
The non-ringed OS32 is meant to run hot. I've been flying mine around 190deg F (+/- 20deg). The tapered design of the cylinder wall is such that it is meant to expand at one end while running. Running a non-ringed engine cool will cause premature wear.

Pinch test:
After warming up (hover for a while), bring the heli back down and pinch the fuel line just before the engine. The engine speed should stay stable for about four seconds and then go a little faster as the engine is starved for fuel. If it reacts faster than four seconds, then it's a little lean. Slower than four seconds and it's rich.

Fuel foaming:
If you have a lot of fuel foaming, it could be because you are running too lean.

Smoke:
The fuel I fly (CoolPower 15) doesn't smoke a lot. I always hear comments that I'm not producing enough smoke. After messing around a lot with my mixes, I've come to the conclusion that my minimal smoke is not an indication of a lean mix.

-Mark

[edm3]

Mark,

Thanks for the info. I am running cool power 15% on a non ringed os32. I have not seen any fuel foaming and do get a fair amount of smoke but I have no experience to say whats a lot of smoke.

I will try the pinch test on the next flying session.

Thanks again.

Ed

[marked23]

Oh, I forgot to mention a key point above... The pinch test is just for setting the idle mix needle. Once that's set correctly, then fine-tune the main needle.

-Mark

[blakka_1]

I have not seen any fuel foaming and do get a fair amount of smoke but I have no experience to say whats a lot of smoke.


Try downloading some of the videos from the "Video section" and have a look at how much smoke is coming from a couple different heli's, that should give you a decent judgement on the amount of smoke you need. :)

PS. Too much smoke is better than not enough smoke.

[DavidH]

Try downloading some of the videos from the "Video section" and have a look at how much smoke is coming from a couple different heli's, that should give you a decent judgement on the amount of smoke you need.

The above might work if all the pilots in the videos were flying 15% fuel. But most 30% fuel on the market will still be smoking well, even when the engine seizes up from being too lean. From my experience you can't nessecarily judge the mixture of the needles all the time by the smoke trail.

Ed,
From your posts, I would think you have the engine tuned fairly well for hovering. Really not putting to much of a load on the engine when it is hovering. If the engine is running consistently for you. I would leave the needles along till you get a little more time on the engine.

David

[edm3]

Dave,

One thing I was told to try was to touch the base of the engine after hovering and if I could touch without getting burned then the mixture should be okay. I tried that and found the base of the engine was hot but I did not get burned after touching it.

I'll give the videos a look as well.

Thanks for the info.

Ed

[edm3]

Nigel,

I'll will try looking at the vidieos to get a better idea of what is a normal amount of smoke.

Thks for the help.

Ed

[DavidH]

The engine will be quiet warm afer running. But if you can touch it and not be burned your OK. When it is too lean and has been run a while that way. It will raise a blister as soon as you touch it.
Your in Washington state. There is a lot of good pilots there. See if you can hook up with some of them.

Here is an event in the state.
http://www.helifreak.com/about6418.html

PM some of those pilots and see if they are close to you.

David

[marked23]

Brooks, OR is actually closer to him... and it's sooner... In June. 17~19.


-Mark

[edm3]

David and Mark,

I will be heading for Brooks OR, it's only a couple of hours south of me and if I can I will be at the July event as well.


Thanks for the info.

Ed