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73 240z L6 problems

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So I have this 240z sitting in the garage for 12 years and found time to work on it. I replaced the fuel,flushed out the line replace the filter and,cleaned the carburetors. I set the float levels with a sight gauge to 19mm below the fuel bowl parting and adjusted both needles 3 1/2 turns out. This has a Crane XR700 ignition and was set so the timing window opens on the edge of the sensor at #1 cyl TDC. The sensor was inspected and is clean.

The problem that I am having is it only runs at 40 degrees advanced at 1000 rpm when using a advance timing light. Vacuum advance is disconnect and plugged at the manifold  Mechanical advance is tight and seams ok. When trying to sync the carburetors, The front carburetor is at 25" and the rear is at 5". Have not looked at the plugs.

The front carburetor piston sits about a 1/4" higher than the rear. Choke butterfly's are open.The fuel pump is a Carter P60504 and is rated at 4psi and when fuel return line is plugged and engine not running the pressure is 2.5-3psi.

Any suggestions?

Edited by p9011

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Removed the plugs and they look similar and are dark brown color. Years ago I did have a crank trigger ignition and forgot the plugs gap were set at .025, these are reset at .040. Lost the coil wire and bought a new 7mm one and after reexamining the coil end found that it did not go in enough. I think there was a coil resistor that came with the coil, but lost that also. So I modified the coil terminal so it now has a solid contact. Will test this to see if this caused the timing problem. 

Had the car over 30 years and was converted to a V8, then L6 turbo and now going back to stock. Just about done with this project and hope to get it running and up for sale. 

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