Bradpabst

Trying to start car thats been sitting for a while. When the key is on the pump runs but fuel keeps flowing from the outlets in the carb. What would be causing this? A stuck open needle or floats stuck? Also what causes the pump to stop pumping when the bowls are full, or is it a retrun line system.

RXnos1200

iTrader: (24)

Sounds like you figured out what the problem is. The fuel pump is always running. When the float reaches it max point, it shuts the needle that lets in the fuel to your float bowl. So when the needle shuts the fuel should go back out the return line back to the tank. If the needle is stuck then the gas is going to start flowing into the carb. Good luck.

nighthawk34

or you can waite tell the tanks is dry and it should stop.. I KIIDDD I KIDDD... I hade that problem on my 84.. I cant remember how I fixed it.. Mine was a electical connection!

Bradpabst

Well well check the check valve to the return to the tank, its good. and the return line i can blow through so its not there. Would the floats be the next place to look? maybe there full of fuel and not closing of the carb? Any help is apriciated. Is thre anything else that can cause these symptoms?

RXnos1200

iTrader: (24)

Is there a glass site on the side of your carb. The fuel level should be about half way up. If you can't see the fuel level in the glass site then it's probably way too high.

Bradpabst

good shot man, the fuel is over the sight glass. Thanks for the info, I did not see that there. I guess the question now is whats the cause of a over flowing bowl?

RXnos1200

iTrader: (24)

Sounds like the needle is stuck open. When the fuel fills the bowls the floats rise up to shut the needles and should stop the fuel flow and divert it back to the return line. Should be able to see the fuel level in the glass site. Again it sounds like the needle is stuck open. Carb rebuild or get another one that you know is working properly.

RXnos1200

iTrader: (24)

Check the vent solenoid and make sure there is 12 volts hooked up to that as well.
picture and idea provided by bpstrange99 from another post.

Bradpabst

Thanks for the speedy response. This puts me on the right track. I'll let you know how it works out. Brad.

rx_n

Here is an old mechanic's trick, with the fuel pump on and flowing, pinch the fuel line completely off with a pair of pliers for 10 seconds and then unpinch it, do this 10 or 20 times and see if the burst of fuel doesnt wash the dirt out that is stuck in the needle and seat assembly. I have never done this with the car not running, but its worth a try. The needle and seat usually gets a peice of dirt stuck in there which causes the carb to fail. I bought my RX 7 in 98 bleching black smoke like crazy, got it home and did this and it smoothed right out and stopped, drove it for another six years before I had to rebuild the carb. I have fixed half a dozen carbs this way when I was a mechanic years ago.. worth a try.