Hi, I WAS WONDERING IF SOMEBODY HAVE EXPERIENCE TUNING UP A SK ENGINES, I HAVE ONE AND IT IS NO DOING OKEY . I APPRECIATE ANY ADVICE ABOUT IT
THANKS
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Firts off STOP SCREAMING

Second.. WHat exactly is it doing wrong? Fuel Prop etc.. We need details.

I just start with the break-in, the manual say open the HN 1 3/4, but is too rich, I'm playing with the needles but I can not reach a fine tunning, I'm using A8 glow plug and 12x6 apc prop. When I take off the glow driver, the rpm get down even it shut off, at full throttle it sound like it was lean but it does not, I'm confuse...

Usually when the engine dies after removing the glow starter, it means the engine is running too rich. You probably removed the glow starter soon after starting, so you were probably idling. You should try leaning your low end some just to keep it running. Once it will run after removing the glow starter, get the high end set right. This is after break-in, of course. During break-in, you want to be running pretty rich, but not as rich as you're currently running.

Twice in the last 3 years I've seen bad fuel act that way. One was Powermaster 10 or 15%, the more recent was CoolPower 10%. Fresh from hobby store, best needle adjustment at part throttle to start with, pull the glow driver and at idle the engine dies. Fiddle around, get full throttle, and the best one can do with the needle renders an intermittent miss that resembles lean misfire.

You might have a fellow club member spot you a tank of fuel, for troubleshooting purposes, from a known good jug of fuel. In any event, an experienced RC'er might be able to spot something you've overlooked.

Good luck,
Dave Olson

Later : edited for tpyos

With a brand new engine on the first start or so, you need to leave the battery on the glow plug until you get the top end needle set to a rich 2-cycle run.

I have an SK 80 ,Read the instructions that came in the box for tunning. I used the pinch method at full throttle to break it in while using ear protection of course. Go to full throttle with a 12*6 keep it rich say 4 or 5 clicks out from top rpm. pinch the hose to get to the high rpm and let it go. This heats up the cylinder for a period and then cools it down with lots of oil. Do this over and over for a full 10 oz tank. After the break in is done you should switch to a 13 *6 or 13*8 I used both. Tune the high end with the bigger prop and go into rich land with 1 or 2 clicks out. The real work is now setting the low rpm mixture. I recommend taking your time with it. Start by setting it to the factory spec. !QUOT! Step 5 !QUOT! screw all the way in to a gentle stop and screw out 1.5 turns. Start the engine and screw in 1/4 turn or less for each run until the goal of perfect throttle response from idle to full is realized. In my case the low mix was too rich a it cost a couple of glow plugs. I have found that the best plug for the engine is an A3 from OS which is generally used for smaller engines around 25 to 15 or so. I also removed one shim ran 5 % nitro and never had a flame out again. Depending on your skill you may want to stick with 10% and not remove a shim. Do not continue to run high nitro as this engine doesn't respond well to it. Good luck this is a great engine for theses who are willing to work em.

Mine flys my TF P39 over 80mph also it unloads in the sky and really rips.
Eric

So you can read my post

I have an SK 80 ,Read the instructions that came in the box for tunning. I used the pinch method at full throttle to break it in while using ear protection of course. Go to full throttle with a 12*6 keep it rich say 4 or 5 clicks out from top rpm. pinch the hose to get to the high rpm and let it go. This heats up the cylinder for a period and then cools it down with lots of oil. Do this over and over for a full 10 oz tank. After the break in is done you should switch to a 13 *6 or 13*8 I used both. Tune the high end with the bigger prop and go into rich land with 1 or 2 clicks out. The real work is now setting the low rpm mixture. I recommend taking your time with it. Start by setting it to the factory spec. !QUOT! Step 5 !QUOT! screw all the way in to a gentle stop and screw out 1.5 turns. Start the engine and screw in 1/4 turn or less for each run until the goal of perfect throttle response from idle to full is realized. In my case the low mix was too rich a it cost a couple of glow plugs. I have found that the best plug for the engine is an A3 from OS which is generally used for smaller engines around 25 to 15 or so. I also removed one shim ran 5 % nitro and never had a flame out again. Depending on your skill you may want to stick with 10% and not remove a shim. Do not continue to run high nitro as this engine doesn't respond well to it. Good luck this is a great engine for theses who are willing to work em.

Mine flys my TF P39 over 80mph also it unloads in the sky and really rips.
Eric