smitty1001

My Feedback: (29)

When the needle valve is turned clockwise i.e. going "in" that is leaning - and counter-clookwise i.e. "out" is richer, right? I just have to make sure that I don't have it backwards!

Now, the screw on the bottom of the carb - is that the idle screw? And where is a good starting point for that?

Finally, is in-flight mixture a must? I know it is to get higher rpms for takeoff and then richen up as you bleed fuel off but can't you just run a little rich if you have a long enough runway and go without in-flight mixture? I am running out of room for servos!!

Thanks

Smitty

Thud_Driver

My Feedback: (1)

In is lean, out is rich. The screw on the bottom is the guide/retainer for the carb barrel. It needs to be tight.

The idle adjust is the brass slotted adjustment on the opposite side from the high speed needle. In is lean, out is rich.

You'll have to do final adjustments to both in the airplane to get them right. You can get them close on the bench.

Yes, you really, really want in flight mixture control. You need to fly the smoke trail if you want your engine to last. A lean run can take your engine out in as little as 30 seconds for anywhere upwards of $150 to repair. Do a search on this forum for many threads on inflight mixture control. $50 and a servo is better than blowing the engine. The BVM one is about the easiest to use.

Good luck!

wojtek

My Feedback: (73)

the newer os 91s come with inflight mixture arms for the needle valve , and also a remote needle if you want ..


Wojtek