Problem after Fuel line change

Sounds like Air in the lines.

If it has been sitting for three weeks, the carb bowls may be only half full.

Here is the catch;  the bowls won't fill until you start it and it won't run until the bowls fill.

This is one of the reasons Electric AUX Fuel pumps are recommended.

If you have one, turn it ON for 30 seconds before cranking.

If you don't have one, crank for ~20 seconds with the MAGs OFF to pump fuel into the carbs.

Then try starting again. it may still sputter but it should clear up quickly.

Do not burn up your starter.

If you need to repeat the process, crank for 30 seconds Max, But wait for 5 minutes before repeating.

   Thanks so much for the reply.  I turned it over twice with no mags.  I choked it and it started right up, running smooth at about 2800rpm and full choke.  But, the second I started to let off the choke, it would start getting rough and the EGT on the left side would drop like a rock.???

   It would only run smooth at full choke, and everything looked normal with the choke all the way out.

  I did that before work.  Came back late afternoon and went through the same thing again...same result.  As soon as the choke inches forward, left side EGT drops and it starts getting rough, pull back out all the way and EGT will come back up and match the right.

   Is this still air?  Thanks again.

Sounds like debris in your main jet from the fuel line change.

Your Air problem was gone about 5 seconds after the engine came up to speed.

This is a different issue.

The Enricher Circuit (Choke) only functions near idle.

It sounds like a clogged jet problem but I am guessing it is the Idle Jet.

If with the Choke ON, and you advance the throttle briskly to a high RPM and it initially sputters coming through the mid-range and then roars to life, the MAIN Jet is clear.

In any event, the solution is the same, the cleaning of the carburetor is in order.

Next time, be sure to flush out the fuel hoses before you hook them up.

just because they are New, doesn't mean they are clean.

Running the Electric AUX Fuel pump for a minute with the hoses disconnected would flush the lines.

     Well, that sucks. I really appreciate y’all’s help.  Thanks again. -John