Bing carburettor fuel leak
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Bing carburettor fuel leak
I have replaced the Carburettor fuel needle on the Bing carb,and yet it still leaks/floods can anyone suggest next step please?
Re: Bing carburettor fuel leak
Likely the float is not raising correctly/high enough to raise the fuel needle so that it to closes the fuel channel into the float chamber.
Never needed to replace the fuel needle on an old carb myself, when I’ve had problems with fuel leakage it has always come down to float adjustment.
I suppose you could manually check that the fuel needle is correctly sealing by manually inserting it with the carb bowl and float removed, and fuel tap turned on. If no leaks then float definitely the issue.
Sorry not super familiar with the bing carb (not common on seagulls, assume you have a GFP serial 40 motor) and I don’t have the parts manual for that to hand, but just to confirm I am talking about the tiny usually-unfixed needle above the float at top of carb bowl, and not the taper needle that comes down from the throttle valve piston.
Never needed to replace the fuel needle on an old carb myself, when I’ve had problems with fuel leakage it has always come down to float adjustment.
I suppose you could manually check that the fuel needle is correctly sealing by manually inserting it with the carb bowl and float removed, and fuel tap turned on. If no leaks then float definitely the issue.
Sorry not super familiar with the bing carb (not common on seagulls, assume you have a GFP serial 40 motor) and I don’t have the parts manual for that to hand, but just to confirm I am talking about the tiny usually-unfixed needle above the float at top of carb bowl, and not the taper needle that comes down from the throttle valve piston.
Re: Bing carburettor fuel leak
You are correct Andrew about the float needle I did check it without the float/bowl and it was fine-I have ordered a new float but was not aware of the adjustment that can be made to a float on the Bing carb and it is not so easy to rplace the float without distorting the pin holding the float-hopethat makes sense and thanks again.
Re: Bing carburettor fuel leak
No standard way to adjust per se, rather a bit of gentle coercing is occasionally needed when reassembling the carb. As you say it’s hard to do much without breaking the pin or float but I’ve overcome same issue in the past with other older seagull carbs.
If you have any more troubles with the Bing carb after installing new float, suggest just swapping it for a Villiers. Readily available in good used condition, John at SOS can supply including conversion to 25:1 oil ratio.
There is probably a reason British Seagull only used Bing carbs for a very short time compared to Villiers which were fitted for decades. Maybe a temporary supply shortage at Villiers. Others on the forum would know the history here and I’d be interested to learn if they want to chime in.
If you have any more troubles with the Bing carb after installing new float, suggest just swapping it for a Villiers. Readily available in good used condition, John at SOS can supply including conversion to 25:1 oil ratio.
There is probably a reason British Seagull only used Bing carbs for a very short time compared to Villiers which were fitted for decades. Maybe a temporary supply shortage at Villiers. Others on the forum would know the history here and I’d be interested to learn if they want to chime in.
Re: Bing carburettor fuel leak
That is interestin-I am goint to replace the float and see what happens-I have a couple of spare engines with the Villiers carburettors as a plan B but ideally the Bing carb needs/should work Thanks again Andrew