1986, 110hp Johnson running rough

[Capt dave 258]

Greetings. I have a 1986, 110hp Johnson, V4 that is running rough. Compression is as follows; top starboard cylinder is 100, lower is 105. Top port side is 105 and lower is 100. When pulling the plug wires one at a time as it's running there is no noticeable difference on the two port side cylinders. Pulling the starboard side wires makes the engine want to die. I switched the plugs from one side to the other and there was no difference. I put different coils and CDI on the starboard side and still no difference; runs about the same with each coil wire off. As I'm reattaching each plug wire on the port side I can hear it sparking significantly. Any idea what could be the cause of it running the same (rough) with the port side wires off or on? What can I do or look for next? I should also mention that the VRO has been deleted. Thanks in advance.

 

[racerone]

Good compression would show about 130 on my gauge.----So you have a bad guage or a motor that needs work.----Pull bypass covers on the 100 PSI cylinders.----Look at pistons / rings.