millertym2000

My Feedback: (4)

I have a 46LA that I cant seem to get to Idle very long. I've tried adjusting the mixture screw but that just made it when I pull the glow plug and bring it down to idle it dies before it makes it to a slow idle. I can get it to where I think its close and it will idle for about 90 seconds, just long enough to think its ok and sit it down on the runway and have it die. It will last about 90 seconds and then it dies for no reason. It sounds like it is idleing fine and the transistion sounds good. any Ideas?

goirish

Not familiar with the LA series, but it sounds like the lsn is to rich. Maybe it starts to load up. Don't think the hsn has much to do with the idle.

microsprint9

Bad plug? or you need to adjust the air bleed screw not the high speed needle, it's the one with the spring on it sticking out on the top of the carb, only a 1/16 turn at a time til you get it and remember turning it out will lean it, as it lets more air in. Also make sure that little hole in the carb under that screw isn't plugged.

goirish

Thanks microspint9, Like I said I was not familiar with that series motor. But it does sound like it is to rich.

Top_Gunn

My Feedback: (6)

That's not the air-bleed screw, it's the throttle stop, which sets the limit on how far you can close the throttle. The air-bleed screw sticks straight out beside the throttle horn.

microsprint9

OK, so it's not quite exactly on top, but it's the screw with the spring on it, the throttle stop has no spring, see part #5, sorry for not posting the pic, here you go....
and in the middle is the hole that you should make sure is not plugged.

Top_Gunn

My Feedback: (6)

Both the air-bleed screw and the throttle stop should have a spring. I just looked at mine; except for location, they're close to identical. The throttle stop sticks up and a bit toward the back, the air-bleed screw sticks straight out to the side.

Nathan King

+1

Start the air bleed screw so that it is halfway blocking the little hole. Adjust from there. Loading up is a sign of a rich low end and abrupt quitting is a sign of lean settings. You can use the pinch test to verify your suspicion.

bruce88123

Air bleeds can be hard to adjust because they are more sensitive than "standard" carbs. Some even need to have the bleed hole enlarged to lean the engine enough but do that as a LAST resort. Non-ball bearing engines don't always idle as well as those with ball bearings and/or need more break-in time.

microsprint9

Hmmmm that's odd the exploded view of the .46LA carb shows no spring on the throttle stop screw and i just pulled the throttle stop screw out on my .40LA and there is no spring on that screw.

Anyways the one circled in my first pic is the air bleed screw on a OS 40D carb which is used on the .46LA.

millertym2000 have you made any improvements in the operation of your engine ?

bruce88123

It's a fixed stop. Use the servo for idle speed setting. That screw is more like an alignment screw for the rotary barrel. It STOPS it from falling out of the housing.