[voyager_663rd]

OS 1.08, mounted sideways, pitts muffler.

Took it out of storage today for run up, etc. Turned over and fired first flip.

Downward transition is a problem.

I can run it at idle with no flooding (I'm talking 2-3 min here) and put the stick to the roof as fast as you would want to, no problem.

The problem is on the down throttle. As quick as you please down, then it floods after 2-3 seconds (after hitting idle speed).

Fuel just pours out the carb and obviously stalls.

I figured if I can idle for several min and then transition to hi with no hesitation of any sort, reverse should not be a problem either.

What kind of revs should I get with a 16x8? OS says practical range is up to 16000. This is a pretty big prop so figure maybe 12?

Have I got the hi end too rich?

I don't know much about your transition problem but if you can get 12,000 on a 16 - 8 you had better bottle it and sell it, you'll be a millionaire in no time

I ran an OS 1.08 for 1100 flights in a Goldberg Ultimate. My prop of choice was a 15 - 8 ( I think a 16 - 8 is too much prop ) I tried several different brands and the best I could get was about 9,800 on an APC. The OS 1.08 likes to run around 9,500 - 10, 000 rpm's.

12,000 on a 16 - 8 ABSOLUTELY IMPOSSIBLE even with a tuned pipe.

[voyager_663rd]

I only guessed at 12 (because of the "posted" 16 on their website--smaller prop obviously).

When I tached it, it was 8000 (with the 16 . I was never happy with the prop it came with (15 8--bought the whole bird used) as I figured it should have more stump pullin' power.

I couldn't hang it with that. The 16 8 gave me a bit more "satisfaction" if you know what I mean. I didn't want speed, I wanted "hang-ability".

This flooding problem on the downstroke is something new.

[Ken Currell]

Hi

Just some suggestions.

I assume that it was running properly when it was put away. The first thing I would do is put in a new OS plug. The second thing is to make sure you have fresh fuel.

If the problem persists clean the carb, and needle valve assembly.

Good luck

[voyager_663rd]

ya, fresh fuel it ain't. dregs. Never had a problem with leftovers b4 but always a first time. Sometimes the obvious escapes us.

try again tomorrow. will post the results.

Thanks

[Heli_Gal]

I would lean up the low end 1/8 of the turn. Sounds like your low end idle is a little on the rich side ie: raw fuel spitting out of exhaust as throttle down.

[voyager_663rd]

Originally Posted by Heli_Gal

I would lean up the low end 1/8 of the turn. Sounds like your low end idle is a little on the rich side ie: raw fuel spitting out of exhaust as throttle down.

You know Naomi, I seriously considered that but concluded because of the long idle to full speed transition with no problems, the reverse should be true also.

I did try to adjust it but it's different on the 1.08 (no screw in the barrel). I didn't have the manual to see where it is so it'll wait till tomorrow.

Definitely a possibility.

Thanks for confirmation.

[Heli_Gal]

Is your with the remote needles at the back of the crankcase? 1.08FSR

Here is the manual

http://www.osengines.com/manuals/108fsr-manual.pdf

[voyager_663rd]

Thanks Naomi. I do have it. I just didn't have it at the field.

Easiest thing is to clean out the needle/barrel. It's enclosed so a pain to disassemble.

Just as I'm putting it back together, the rains started. Haven't had a chance to test it yet.

I have a feeling it was just dirt or something in there. A new development prior to this cleaning was:

I could idle all day no problem but if I gradually moved to half throttle and held it there, it would run, run then just die. No zoom up then die like you might think if it was too lean. Just stopped dead. Ya this is different from the previous post (ran full no problem and flooded out when pulled back to idle).

There might be more here than meets the eye.

I wait for the weather to improve a bit & I'll post again.

[Heli_Gal]

Have your use a filter between the tank and the carb line.. That would definitely helps.