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MG MGA - carburetor issue

When I went to pull my 56 1500 roadster into the garage, I smelled petro. I stopped the car and noticed gas poring out of the carburetor drain tubes. As soon as the ignition is turned on and the fuel pump starts the fuel starts flowing out of the drain tubes. Any ideas on how to fix this will be appreciated. I have never worked with carburetors before. I am a little nervous.
Terry Marcus

If it is happening on only one carb, the float in the carb is stuck, or the needle valve has some dirt in it. It would be surprising if a problem appeared in both carbs at the same time unless it is down to dirty fuel.

On the side that is flowing, remove the bolt that goes through the banjo on the drain tube. This is on the top of the chambers on the outer sides of the carbs. This will allow you to remove the lid and look into the float chamber. If the float is not floating, then you need a replacement or two.

If the float is bobbing on the surface of the fuel, carefully pull the pin that holds the fork onto the float chamber lid ( no tools required, but make sure not to drop it when reassembling), and that will allow you to take the needle out of the fuel valve. It should have a nice sharp point on the end of it, make sure that there's no dirt in there and put it all back together as you found it. If it was fine before, it will probably work fine from that simple clean and reassembly.
Dominic Clancy

My recommendation is to replace the float needle on both carbs with grose jets.I had the same problem with my carbs way way back, but never again since I installed grose jets.It would also be wise to check the floats for any pin holes or cracks.

F. Camilleri

You could also give the float a shake. I had a leaking float last year and it then sat too low and caused these symptoms. Solution, get new float.

Paul Dean

I had the exact same problem with one carb on my frogeye. As everyone has said, the float chambers are the place to look.
The link below will take you to a very useful article by Dave Dubois, I recommend you read it, it certainly helped me (belated thanks Dave if you are reading this!)

Good luck, Graham
Graham V

As s follow up to my carburetor issue that's to the guy who helped with instructions. I follow Dominic's instructions and found the task relative easy. I removed and cleaned the jets in both carbs. I did not find any dirt but upon completing the job the car runs fine. thanks again for all the help..

Terry Marcus

Well done Terry. The only problem is that often the same problem will return. If not, great, but if it does, I would recommend just unscrewing the old jets and replace them with Grose. In my experience once the jets start misbehaving you might as well bite the bullet and replace them. However, good luck for now.
B Mayo

This thread was discussed between 21/10/2016 and 24/10/2016

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