Few questions...Is it normal for fuel to seep out from the throttle bases where they meet the intake manifold? All of the cylinders seem to be running decent when I took out the spark plugs(light tan color) except for 2. The two that werent the tan color are black, but not wet. What is the reason for this? This is with a 2x2 setup running direct linkage....4.5 power valves and 50 jets. Flathead with isky max-1 cam. It would be great if someone could answer these questions. Thanks!
To answer your question.....................No leak is normal. Are you sure the leak is coming from the gasket area, or could it be coming through the throttle shaft? If it is coming between the base of the 94 and the intake either the 94 base has a warped, the intake base is warped or the gasket is not sealing. Replace the gasket after looking at the 94 base (put a straight edge across it to make sure it is not warped and do the same with the intake manifold base), then take a good look at the carb/intake gasket to see if you determine why it is leaking........................then replace it. As for the black "carbon or unbrunt fuel", on two of the plugs it's alittle hard to tell unless you give more information. What cylinders are running black? Since the other 6 are apparently running normal have you checked the wires on these two cylinders for cracking or loose connections at the plug. What happens when you take two of the "brown colored" plugs and put them in the cylinders that are running black. Have you put a vacuum gauge on the motor to see what it is doing.
The two that were black, are they the back 2 cylinders? Also, it's rather common for the throttle shaft to leak fuel due to excessive wear. Oversized throttle shafts are available for replacement. (Though I would suggest checking for warpage) Had a truck with a flattie in it that would run fat in the rear 2 cylinders.
If it is the throttle shaft that is leaking, you can get new replacements that are stock diameter from Charlie Price @ Vintage Speed. There is usually no need to ream them oversize as the shafts are br***....................the shafts wear and not the cast iron bases. Check this before going to the trouble to have the bases reamed oversize. To get this right you need to make a fixture to hold the reamer exactly dead nuts parallel to the base..................because not getting the shaft straight in the housing will just cause it to leak again. IMHO
A couple more things to look for. If you are running an electric pump with no regulator or the regulator is not set low enough, this is the first place the fuel will seep. Also, same thing will happen if float is to high.
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