I would think if one of those monsters got loose enough to shift, you would feel it all thru the boat. Good to hear you got them secure.

Kinda doubt you could hear an electrical/ign pop with engs running, hatch closed plus the wind noise. If it was electrical and that loud, there should be evidence.

When you mentioned new fuel pumps, it reminded me of when I got my current boat and prev owner had recently replaced the fuel pumps (and a bunch of other stuff). Fuel press was intermittently low causing an intermittent lean condition and "pops" thru the intake..Eventually,,, found tiny shards of teflon tape inside the fuel pumps. They were not allowing the check-valves to seat and causing low output press.

Got fuel press gauges on the fuel lines now and check them every time I open the hatch.

If it were me, I'd at least check the fuel press at idle before putting a heavy load on it again. Lean conditions have destroyed many many engines.

Good advice ^^^*
Further tound table talking….

can’t tell you how many times i’ve jumped someones bsttery, gone on a test drive ‘for something else’ and then use trim or tabs and ‘pop, pop, pop, pop’ like firecrackers and engine slows down. Bad battery (not low in charge, but bad, all done, no bueno) sucks sll the juice from alternator leaves barely enough for ignition but nothing else.

That’s a great thought on it leaning out. Now that I think about it I ran about 10 miles today at 27-2800 but when it popped up to 30-3100 I started having the issue. I’m going to investigate fuel side tomorrow…….

When in doubt, just turn up the stereo!
Drives me nuts tracking down stuff like that.

Yeah, I swear by the Walmart EverStart Maxx marine 29's. (20yrs use) The Optimas were used in my solar system and friends boats. They were all bought at cost when my friends worked at JCI. Funny things is the EverStart batteries are also made by JCI. I know 2 different technologies.

JCI, Johnson Controls??

Probably. They make a LOT of different branded batteries out there. I think Exide and Deka are the other manufacturers, that's about it.

Good to know, thanks.

Alright - oreilys had a fuel pressure gauge. Installed after regulator 6 lbs of pressure.

New Battery installed.

engine bolted down!

checked fuel filter, not even a drop of water. I did notice it was “hand tight” at best. Wonder if some air was nearing in. Doesn’t seem likely though.

going to go give it the smoke test….

strike that. Probably 30 mph winds here. I don’t feel like dealing with that. Forecast for 5mph tomorrow. Seems like that’s better test weather….

Fuel pressure is OK, I'd personally like to see it a bit higher (i.e.7.5 psi) if it's adjustable. The fuel pressure is much more critical at higher power levels.

If still no joy tomorrow, could try swapping carbs between engs to rule that out. Quick, easy, free.