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-   O.S. Engines Support (https://www.rcuniverse.com/forum/o-s-engines-support-133/)
-   -   OS MAX-40LA needle valve (https://www.rcuniverse.com/forum/o-s-engines-support-133/3756007-os-max-40la-needle-valve.html)

thermund 01-10-2006 09:46 AM

OS MAX-40LA needle valve
 
Greetings Bill,

I have been reading this forum and I'm highly impressed with your patience and expertise in answering all questions. Here's my ignorant newbie question:
I have a brand new OS MAX-40LA that I have installed on a trainer, and have just begun to break in. From reading this forum and other online sources, the needle valve should be opened about 2-1/2 turns to start the motor. On page 16 of the booklet that came with my motor, it says to open the needle valve 1-1/2 turns to start the motor. Can you please address this discrepancy?
I have read the instruction booklet cover to cover a couple of times, and have been following the instructions carefully, but I'm concerned that I may have been running the motor too lean for its initial break in period. I've only run about three airplane tanks of fuel through it at low throttle, with occasional run ups to high throttle. I have not flown it yet. It has the recommended 11x5 prop, and seems to be running OK. I would really appreciate more detailed advise about this motor, or a link to a good newbie site for more info. The booklet didn't answer all of my questions. Thanks in advance!

Bax 01-10-2006 10:42 AM

RE: OS MAX-40LA needle valve
 
Opening a needle farther doesn't hurt a thing. It will just make the engine richer. You'll need to lean it as the engine is run in. many times, a final setting is close to 1-1/2 turns out from closed, so we usually recommend opening it a bit more and going from there.

You can go to the O.S. FAQ page at the O.S. website.

http://www.osengines.com/faq/index.html

A lot of info there!


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