O.S. FS-70 Ultimate Set up question
04-15-2005 | 11:05 PM
#1
Thread Starter
My Feedback: (7)
Joined: Sep 2003
Posts: 42
Likes: 0
Received 0 Likes
on
0 Posts
From: Souderton, PA
O.S. FS-70 Ultimate Set up question
Setting up the needle valve was pretty simple but I am having problems with transition and idle.
Once I set up the needle valve, then I set the idle mixture to 1/2 in from flush. Usually have good transition at this point.
But if I continously test the transition, the engine stalls out at about 4-5th attempt. I does not matter whether the transition is fast or very slow. First few transition is very good but eventually stops. I've tried many diffrent mixture setting, but it does the same.
I used 15% cool power and tried 25% cool power. I spend about 3/4 gallon of 15% fuel so far. The idling is getting worst as I spend more fuel. 25% cool power improved low RPM but could not run the engine below 5000 reliably yet.
What is best way to set up the mixture valve?
I read somwhere in the past post that two turn in clockwize from flush is rich setting. I thought it is the otherway. Isn' t is the clockwize turn of the mixture valve lean?
thanks
Once I set up the needle valve, then I set the idle mixture to 1/2 in from flush. Usually have good transition at this point.
But if I continously test the transition, the engine stalls out at about 4-5th attempt. I does not matter whether the transition is fast or very slow. First few transition is very good but eventually stops. I've tried many diffrent mixture setting, but it does the same.
I used 15% cool power and tried 25% cool power. I spend about 3/4 gallon of 15% fuel so far. The idling is getting worst as I spend more fuel. 25% cool power improved low RPM but could not run the engine below 5000 reliably yet.
What is best way to set up the mixture valve?
I read somwhere in the past post that two turn in clockwize from flush is rich setting. I thought it is the otherway. Isn' t is the clockwize turn of the mixture valve lean?
thanks
04-18-2005 | 01:24 PM
#2
My Feedback: (11)
RE: O.S. FS-70 Ultimate Set up question
With your pumped engine:
1) The high speed needle must be set as lean possible without detonation or RPM drop, and left there. DO NOT lean to peak and then richen a bit.
2) Set the idle only after the full-throttle mixture has been found. Set it wherever you have to set it to get a good idle.
3) Acceleration mixture is adjusted with the idle mixture. You may have to alter your idle RPM to help get a good acceleration.
4) Please be aware that your engine will need a few gallons' worth of running before it starts to really "come in".
5) Cooling is very important! A closely-cowled engine will need some cooling air over the crankcase, especially towards the rear. If it's not cooled well, the pump can get warm enough to encourage fuel vaporization in the pump.
1) The high speed needle must be set as lean possible without detonation or RPM drop, and left there. DO NOT lean to peak and then richen a bit.
2) Set the idle only after the full-throttle mixture has been found. Set it wherever you have to set it to get a good idle.
3) Acceleration mixture is adjusted with the idle mixture. You may have to alter your idle RPM to help get a good acceleration.
4) Please be aware that your engine will need a few gallons' worth of running before it starts to really "come in".
5) Cooling is very important! A closely-cowled engine will need some cooling air over the crankcase, especially towards the rear. If it's not cooled well, the pump can get warm enough to encourage fuel vaporization in the pump.
