Carb Flooding engine

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Well I think I found the problem. I removed the carb and found that the main needle clip had broken and the needle was stuck high up. The movement of the slide has scratched it thoroughly so I will need a new one. Thanks to all of you for your help.
How does that affect flooding situation?
 
The needle clip is probably not broken. That's the way they are. When you put the slides in you need to guide the needle into the hole with your fingers.
 
Well I think I found the problem. I removed the carb and found that the main needle clip had broken and the needle was stuck high up. The movement of the slide has scratched it thoroughly so I will need a new one. Thanks to all of you for your help.
Good. The needle clip is sometimes seen as "broken". It has a split in it from new . Hope that helps.
 
You might need a new needle jet as well. But the needle being "disengaged" has nothing to do with the carb flooding the engine.
That is an issue with the float and the float valve.
 
You might need a new needle jet as well. But the needle being "disengaged" has nothing to do with the carb flooding the engine.
That is an issue with the float and the float valve.
Are your carb bowl gaskets reversed / upside down ?
 
I am not sure what you mean by the gaskets reversed. They only go on one way.

My only thought about why this could cause the flooding is that as soon as the bike started it would draw a ton of gas into the carb and engine. When I shut it down all that gas in the open jet could continue to draw through capillary action for at least a period of time. Now that I think about it I was not getting flooding through the tickler before starting the engine once I adjusted the float heights, but only after. I know this is a wild thought and may be wrong.

I have checked the ticklers every which way with the carbs apart and am convinced that one is not holding down the float.

This bike would have made a beer drinker out of me if I wasn't already.
 
You say you have new stay up floats in original carbs. I didnt read anything about adjusting the float needle seat height in the bowl. In Greg's tour-de-force treatise on fuel levels given above, he mentions stayups can be too high, interfering with carb body if seats are too low from previous original float settings. Also note he mentions a bit of plastic flashing on top side of new stay ups that can interfere with carb floor, needs trimming off.

Tell us how yours measure compared to Gregs images and guidance.
 
I used the method covered in the link provided by TomU in this thread, holding the bowl upside down to measure the distance between the top of the float opposite the needle side and the lip of the bowl. I set it at .040. In other words when right side up the float is .040 below the rim when the needle is seated. The float is therefore substantially lower than that in the Greg Marsh link in which it is actually higher than the rim.
Amal must use a different way of casting the floats as mine do not have any of the little plastic projections shown in the article.
 
I used the method covered in the link provided by TomU in this thread, holding the bowl upside down to measure the distance between the top of the float opposite the needle side and the lip of the bowl. I set it at .040. In other words when right side up the float is .040 below the rim when the needle is seated. The float is therefore substantially lower than that in the Greg Marsh link in which it is actually higher than the rim.
Amal must use a different way of casting the floats as mine do not have any of the little plastic projections shown in the article.
Yes .04" below lip is where the amal guidance is for original floats. I believe stay up spec has changed since original reference materials appeared. Either way, Greg's procedure sets liquid height, not float height as liquid level is what is actually important.
Either way, if you are confident in your bowl swapping conclusions, that problem does not move with the bowl, then we need to focus elsewhere. I cannot see how a displaced throttle needle can give carb flooding unless as you surmized, it only happens while actually running, such that fuel is being drawn in to flood via engine vacuum. Id expect that side plug to foul and run very poorly at idle if true.
Also, can you rule out something like a fuel line or petcock leak which trickles down to drip off carb but appears like carb tickler is where it originates?
 
I used the method covered in the link provided by TomU in this thread, holding the bowl upside down to measure the distance between the top of the float opposite the needle side and the lip of the bowl. I set it at .040. In other words when right side up the float is .040 below the rim when the needle is seated. The float is therefore substantially lower than that in the Greg Marsh link in which it is actually higher than the rim.
Amal must use a different way of casting the floats as mine do not have any of the little plastic projections shown in the article.
That puts the fuel level a good bit below where Amal says it should be. The top of the bowl is not the bottom of the carb body - there is a gasket between and the bottom of the carb body is about 0.050 above the mating surface. So, there is plenty of clearance when setup as I do, and what I do matches Amal's specifications.
 
I will put the bowls in my jig to test liquid level per your comments. At any rate my current lower setting is not causing the flooding.

Yes the spark plug fouls quickly in less than 10 seconds and gas comes out the muffler in about 20 seconds. The rate of flow I assume is caused by the throttle needle up out of the main jet.

Once I have done both I will see how it goes.
 
Problem solved! It took me awhile to get back onto this but putting the clip back onto the main needle did the trick. Bike runs great.

Thanks to all of you for your assistance.
 
I had a problem one time and found the "nitrile" tip on the float needle was bulging on one side. This caused the tip to be offset and flood. It wasn't easy to see but fitting a new needle fixed the problem.
Dereck
 
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