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Carburetors Overflow

Redgazelle1

Freshman Member
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A few weeks ago I replaced the original carburetors on my BJ7 with new ones from Moss Motors; however, since then I have experienced problems of petrol consistently pouring out of the overflow. Any suggestions with solving this problem?

Thanks.
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It seems funny that this should coencide with new carbs. My experience is that this is a "dirty fuel" problem causing the floats to stick open. Check the bottom of the new float bowls and see if there isn't some "crud" down there. Crud can come from fuel lines disintegrating, fuel tanks rusting, fuel lines decaying and outside contaminants, like the grand son placing a handful of dirt under the shiny thing on grandpaws car....

It could also be that the new carbs have defective needle valves or floats, but it seems unlikley that both carbs would be bad.
 
[ QUOTE ]
A few weeks ago I replaced the original carburetors on my BJ7 with new ones from Moss Motors; however, since then I have experienced problems of petrol consistently pouring out of the overflow. Any suggestions with solving this problem?

Thanks.
/ubbthreads/images/graemlins/england.gif

[/ QUOTE ]

Check that the fibre washer 'sealing' the overflow banjo to the top of the float chamber is not a plain one but the one with three cutouts. If the wrong washer is put in, as things warm up the pressure builds up from evaporating fuel and the only way out is by blowing fuel through the overflow. If the correct washer is fitted then pressure is releved by vapour escaping.

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Don't know if this is your problem but...I had a similar overflow problem with one of my carbs and it turned out the brass float inside the carb bowl was not floating due to a leak (the air leaked out and it filled up with gasoline). I replaced the float and the problem was solved. Leaky floats can be fixed (with solder) but I didn't go this route.
 
a little while ago we had this overflow problem, and it was the carb needle sticking(probably dirty fuel. Didn't take too long to fix

sjoerd
 
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