07 Volvo Penta 5.0 GL-H Vibration

[void7910]

I started my boat this year after storage and noticed the engine was running quite rough. The distributor cap contacts were corroded to poop as someone had installed a non-brass auto part and the plugs looked original. Ended up changing out the plugs, distributor cap, distributor rotor, belt and impeller. Cleaned up the flame arrestor as the old belt had shed a bunch of rubber. After firing it up the engine sounds much better, it's almost purring. The one thing I noticed though is there is a fair amount of vibration. It's worse at idle cold but still present at idle warmed up. I can see the fuel separator mount shaking but the boat itself only rumbles a little bit, is that level of vibration normal on a GL-H (sitting in the driveway)? Thoughts as to the source? Bad plug wire (they look old but no cracks or corrosion)? Compression? Other?

Thanks all!

 

[dubs283]

is the firing order correct?

1-8-4-3-6-5-7-2

did you check/set the timing and adjust the carb?

 

[void7910]

Good call in firing order. I re-wired the exact way it was before, for better or worse. I haven’t timed an engine before, as I am just a weekend warrior. Didn’t adjust carb as the engine didn’t sound like it struggling or surging.

Good things to look into. Thanks

 

[void7910]

Follow up. Potentially found the issue. After checking the firing order and connections I tested the plug wires with a multi meter. No idea what the spec is on these but roughly half of them measured at 10.6 - 10.9 kOhm and the others measured at ~6.4-6.8 kOhm.

EDIT; Maybe not the issue, I am an idiot resistance is by foot will need to take that into account