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Discussion Starter #1
I have a small problem with some dellorto's - number is DHLA G. The problem is that when idling, one side of the carby will spit fuel out of the throat and it slowly pools in the air box area. This ONLY occurs at idle and when revved, the fuel disappears and car runs fine. It's only just started happening recently and the carby's have had a kit put through them only a year and a half or so ago. Additionally, the mixture for that particular throat is very rich (mixture screw done up all the way) and the plug usually fouls up making it stumble at take off and makes it hard to start. I have taken the jets out and cleaned them, also cleaned the mixture adjustment screws and checked the float level. After taking off and picking up revs, the car will run fine. There is no backfiring out of the carby or anything and all the other plugs look good. Car is an Alfetta by the way. If anyone could help it would be greatly appreciated.
 

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You could have a bad needle and seat on that carb. It could be dirty/sticky or worn. At idle it is flooding the carb and as the fuel in the bowl goes down as your drive, the level is normal and the needle/seat is able to keep up. Is there a screen before the needle or a filter that should be cleaned and checked also?
 

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Discussion Starter #3
Yeah there is a little filter inside the fuel line right before the needle. I will make sure it's clean. Can the needle be taken out without removing the float? I have a spare set of carburettors that I can try and swap parts with - not sure what condition they're in though.
 

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Just remove the top of the carburetor, slide the pin out that holds the float, and then just use a wrench/socket for the needle/seat. The needle is longer than the drop of the float in most cases. I wouldn't bother cleaning it, just replace it. The needle/seat come as a pair, I wouldn't switch parts. If you have a spare, your blessed. I have a junk Dellorto in a box somewhere, if you get in a pinch, I can go dig for the needle/seat.
 

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Discussion Starter #5
Ok I'll take the needle/seat out of the spare I have - is there any way to tell if the spare one is worn as well before I go to the trouble of changing them over?
 

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No, just put it in and see what happens, it is an easy repair. There isn't really any way to judge that I know of if it is worn. Just be sure you recheck the float level! Also while you are in there, check the float itself to make sure it isn't pulling gas into the float body and pulling down on the needle. Nothing worse than a sunk float in stop and go traffic on a Friday afternoon in Los Angeles. :(
 

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Discussion Starter #7
Just changed them over this afternoon and everything seems fine now!! No more fuel spitting out and it idles a lot smoother, haven't done a cold start yet so hopefully it will start easier too. Also still a bit of hesitation so I'll have to do some fine tuning later in the week. Thanks for your help, much appreciated!
 

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That is why we have the BB is to help each other. Who knows, someday you can help me with a problem. About the hesitation, take out the jets and check the accelerator pump jets to see if they are clogged with varnish or junk. The holes are micro small and it doesnt' take much to clog them. Use your breath to blow through them to check for free flow. That should cure your hesitation. :)
 
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