I have an O.S. .46FX that is about 8 months old....recently I have a hard time starting it, because it floods??? lots of fuel going to the carb for some reason....Its mounted upright, and never had a problem until now.....any suggestions would be greatly appreciated!

Needle settings are OK?

Tank mounted inline with carburettor?

I have found with both of my .46 Fxs is after a while of running perfectly, the engine starts to run rich at idle and is hard to start........I've found the idle mixture screw had backed out and changed the setting, readajust per the instructions and the engine ran fine and started easy again.

I'll give it a try, thanks

Yeah the only way for fuel to get through is through that low end mixture setting. I'd turn it all the way in and count the turns it takes. Let us know how many it was at. Then put it to where OS recommends to start out. Start tuning from there.

I followed the manuals instructions, and found that it only took about 1/4 of a turn to close the mixture screw! I opened it 1.5 turns per the manual, havent run it up yet. what about the throttle stop screw? the manual doesnt say much about it.....I havent adjusted it, but will it ever need to be?

If you haven't already done so I would try replacing the glow plug. I had a 46FX that started running strange- hard to start and wouldn't idle/pick up right unless the low mixture screw was almost all the way turned in. The plug had plenty of glow when I checked it so I thought it was OK. To make a long story short, in the end I finally replaced the plug and the motor went back to running normal.

I wouldn't mess with the throttle stop screw unless you have to. It should be turned out about as far as it can go where it still holds the throttle barrel in solidly. If you go too far out the throttle barrel can slide out of the carb! But turning it in too far can limit how far you can turn in the mixture screws which can complicate things.