Help, 130 Johnson With Problems

[Special48]

Hello, I have a 1997 Johnson 130 with a dreaded intermitent problem. Sometimes it will pull full power and rpm, but occasionally drops power and rpm (4200-4400) and then will pick it up again. I checked at the ramp and have fire at all the plugs. The #1 cylinder is not actually firing (producing power)though. I was able to check that the coil and plug were ok. I've gone through the carb and didn't find any obvious problems. I had compression between 118 and 125 with the misbehaving cylinder the highest. Can someone explain the primer setup I think maybe it could be flooding this cylinder? Is there a primer hose to this carb or intake that could be disconnected causing vacuum problems? The plug didn't look any different than the others. Could the power pack be firing this cylinder out of time? I've gotten frustrated and may have forgotten something basic. Thanks for any help you could offer

[thefermanator]

If you have spark but the cylinder is not firing all the time, I would check the fuel system. Pull the airbox and drain the carbs and see what comes out of them. I had this same problem before and it ended up being that a plug wire had pulled loose from the metal ring that contacts the coil in the boot. Check your wires and drain your carbs and make sure you don't have a piece of trash that is floating around and intermtintly blocking the jet.

[eggsuckindog]

Check the plug wire but those things will throw a spark a 1/2 " so probably not it but check everything. Its probably the Power Pack, look for obvious things but its dropping a cylinder and its either the coil or PP, coils are hard to check though unless the cylinder is dead then swapping will find it, but probably the PP.

[Special48]

Thanks for the replies, I've cleaned the carb on the suspect cylinder and everything looked good. I swapped that carb with the one below it. I swapped the coil with the one next to it. The same cylinder is still weak. Last year there was a head gasket leak that was shorting the trigger wire on the coil of the cylinder that is acting up. I'm wondering if the power pack firing to ground through the water may have damaged power pack.

[Special48]

Hello again, There are four small hoses, one goes into the back of each cylinder. I believe part of the primer system perhaps? The two on the 1 and 3 cylinders were coming off. Number three was off totally and number one was tearing. These are buried behind electronics and the starter of course. We're going out today for the opening of MD rockfish season so I'll get to see if this helped.

[rodbolt]

the hoses running from the intake manifold to the cylinder banks are recirc or bleed lines.
they should not affect high speed but will create allkinds of low speed issues if the lines are broken or pinched or the check valves bad or the valve screens carboned over.
we did see some issues on that motor blowing out the reed gasket.
but myselfwith OMC I tend to check the basics, then usining a CD-77 meter or equivalent test the power pack output to the coilprimary.
or us a Kv tester and check the coil secondary output voltage at the problem RPM.