Are the WYL series carbs suitable for our purposes? Don't see any adjustment needles.

http://wem.walbro.com/walbro/product...rtnum=WYL-10-1

The rotary barrel carbs have a very stiff return spring that also holds the barrel in position. The barrel raises as the throttle is opened which also raises the metering rod. They seem to offer better throttle reaponse because the fuel is metered across the entire range. The stiff spring I think would creat battery drain problems.

Just remove spring or install a weaker one in its place. These carbs give the best running at all speeds. Hope this Helps Capt,n I had one on a 30 cc Boat engine.

The problem is that the barrel must drop back down for it to meter properly. The spring pulls the barrel back down as it is closed. Tried it already on my Ryobi four stroke, idled like crap.

My Honda GX25 came with a WYL carb. Since that carb doesn't have a high end adjustment, it didn't work for me - the engine kept sagging from a lean mixture at full throttle. You need a WYK series if you want a fully adjustable barrel carb. It has a high end adjustment screw on the body of the carb and a low end screw in the top of the throttle arm.

Cheers,
Charlie

i have a wyl carb on my shindaiwa conversion it works great runs perfect all the way through to full throttle. The only problem i had was the return spring on the throttle it was to strong. So i took it out and where the linkage goes to the carb i put a rubberband to hold the tension on the barell. works great though it would be nice if i could get a weaker spring to put in the barell but once i got it out i didnt have much luck getting another one in its place hope this helps

I use the WYL's also on my Briggs and Stratton 4 stroke conversion, we have done four now. Just remove the spring, cut all but two windings off and reinstall, works very well, very little resistance and still keeps the tension. We had to drill out the barrel to get to the mixture adjustment (high end only) but that was no big deal. ours are idleing at 1450 dependably and peaking at 6200 with an 18-6. This doesnt sound all that great but it sure flies our WWI planes great and the sound is super.