88 merc 20hp - not firing 1 cylinder

[pl2442]

Ok guys. Lets start with both coils are fine.
top cylinder fires fine bottom cylinder doesnt fire. I have spark in both. Swich box? Trigger?
How do i test each, i really need to know how to test them.

(I swaped both coils around and still only top cylinder firing)
(spark tester on each cylinder and both have spark)

 

[flyingscott]

What is your compression?

 

[pl2442]

Compression test was 110psi in each cylinder. Coils tested good, even swap the coils and still only top cylinder is running. But as of last night now there was no spark in the bottom cylinder.

 

[pl2442]

Ok guys need help with what to test next. Cylinder pressure is good, spark plugs good, spark plug wires are good, coils good, swich box good (bought new 1 installed and still only top cylinder) where do i go next?

 

[pl2442]

So last night i read to test the trigger (without dva meter) you can swap the brown/white brown/yellow wires to the switch box and the green/white green/yellow to the coils. I jumpered the brown wires and swapped green and the bottom cylinder started running and the top wasnt running. So im assuming the trigger is bad. Anybody have an alternate theory.