'79 XS project by a mechanical newbie. (But hey, it was free)

[stoneairsoft]

I have looked and there is no adjoining passage that TC spoke of between the towers.

Again, I am struggling with 1 & 2 not firing. There is a small amount of fuel that runs to the carbs after initially connecting the fuel line, but the fuel is not getting into the cylinders as the fuel flow stops to 1-2 but 3-4 continues as I run the bike.

Spraying starter fluid into 1-2 works wonders for a few seconds, so I know there is at least sufficient compression/spark to ignite initially. And the coils go 1/3 and 2/4 anyway.

If there is a problem with the vac adv, could that cause 1-2 not to fire? It doesn't really make sense though that 3-4 would when there is no adv connected to them.

I have the carb boot #2 capped and the vac adv hose going into carb #2 is directed.

I took the bank partially apart to check the fuel T between 1 & 2 and there were no issues. I sprayed carb cleaner into every orifice I could find.

[skids]

And the coils go 1/3 and 2/4 anyway.

Say what? One coil fires 1 and 4, the other fires 2 and 3. You have your spark plug wires crossed?

[stoneairsoft]

Sorry. I was thinking firing order?
Regardless. Point stands about it being fuel issue.

I have reused the coils which are labeled 1, 2, 3, 4 and have angled caps for the 1 and 4, making it hard to mix up.

[DiverRay]

Double check your fuel line for kinks, and VERIFY!! the carb bowl vent isn't blocked. On the later carbs it's in the intake bell of the carbs. The early carbs have a second "T" above the fuel "T", and a line goes to the airbox.
Also, check and make sure the float isn't dropped too much. There is a tab on the float that should hit the carb body to keep the float from dropping more than about 25-30mm. Sometimes if the float drops too much, or goes too high, it can stick on the carb, shutting it off or causing it to free flow.