datson240z Posted January 26, 2014 Share Posted January 26, 2014 I has a 72 240z all original. I had to change my fuel pump because it wasn't delivering enough gas. Now as I changed it I get too much gas. And it is mechanical fuel pump from autozone. Every time I drive it I smell gas so I check the carbs and when I took off the air cleaner gas pooled up and fell and when I took off the top of my SUs they were flooded. I did check the fuel jet adjustment and its correct to my knowledge. From books I was told two full turns. And I'm lost. Help? I'll answer more questions if needed. Thank you. Quote Link to comment Share on other sites More sharing options...
beermanpete Posted January 26, 2014 Share Posted January 26, 2014 It sounds like the float vale (needle and seat) are leaking. Perhaps the weak fuel pump was masking this problem. Take the float bowl covers off and check the float valves for wear, dirt, and adjustment. Check the floats as well to make sure they are not sinks. Quote Link to comment Share on other sites More sharing options...
datson240z Posted January 26, 2014 Author Share Posted January 26, 2014 Thank you! I need new floats but, what is your suggestion on the float adjustmeant? I'm kinda lost when it comes to that :/ Quote Link to comment Share on other sites More sharing options...
seattlejester Posted January 27, 2014 Share Posted January 27, 2014 Somethings are a bit concerning... Change the fuel pump because it wasn't delivering enough gas, what does that mean? The stock mechanical should keep up with the SU's. Did you get a replacement for the mechanical pump? What do you mean by autozone? My fear is that you are referring to an off the wall electric pump, if you used the high pressure model, you can be flooding the carb with way too much pressure. Adjusting the jet would not adjust the pressure of the pump, it would just dictate the air fuel ratio. The two turns in the manual refers to the starting point for tuning the carbs for lean or rich, not to regulate fuel pressure. Fuel pooled up in the air cleaner, do you have the stock air cleaner? That would mean the fuel came from the fuel overflow vents and pooled up in the air cleaner. Be very careful, you almost had an engine fire! I would highly recommend finding someone who is familiar with the carbs to take a look, or take the carbs off and take it to a professional. Pete is right on the money, either your needle and seat were sticking, (which could be as easy to fix as a few whacks on the housing with a blunt instrument), you are overfilling your carbs with too much pressure from your fuel pump (if it is an OE replacement that is highly unlikely, if it is an electric fuel pump it is possible), or your floats are no longer floating (they have a crack and are acting like sinks as Pete says). Please be careful. If you have not worked with these carbs before, consult someone who has. And have someone with a fire extinguisher standing by when you decide to try and start it again to be your spotter and your safety worker. Quote Link to comment Share on other sites More sharing options...
beermanpete Posted January 28, 2014 Share Posted January 28, 2014 Thank you! I need new floats but, what is your suggestion on the float adjustmeant? I'm kinda lost when it comes to that :/ Set the float height to the factory setting of 14 mm to 15 mm as described in the factory service manual. If you do not have a copy of the manual you can get one at: http://www.xenons30.com/reference.html Quote Link to comment Share on other sites More sharing options...
datson240z Posted January 28, 2014 Author Share Posted January 28, 2014 The car would suffer for gas and when I would drive it wouldn't accelerate. When I changed my mechanical fuel pump I bought it for auto zone and it is not a remanifactured fuel pump. Yes I do have a stock air cleaner. Thank you very much! Quote Link to comment Share on other sites More sharing options...
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