cylinders 1 and 4 not firing, idles, cuts out with throttle

[andr333w]

hello,

a couple weeks ago, i picked up a 94 seca ii that isnt running.

so far ive replaced the following:

• fuel pump
  pet cock
  fuel lines
  spark plugs

symptoms:

• idles fine (around 1500) with choke open
  exhaust pipes 1 and 4 cold
  exhaust pipes 2 and 3 very hot
  all spark plugs sparking
  all carbs fill up with gas
  compression is fine
  any throttle kills the motor
  any change to choke kills the motor

i've also cleaned the carbs pretty well, short of separating the four carbs. didnt know how to get the cover off for the mixture screw until reading it on this website in the faq section.

my next step forward is to take the carbs off, take out the mixture screws, make sure they are clean, and the holes are clear.

any other suggestions?

thanks,

-Andrew