88 Evinrude VRO 110 - Strange problems

I picked up an 88 Evinrude 110 VRO for a project boat i have been working on. The original 90 melted down a piston and a co-worker offered me this 110 to replace it with but he said he thinks it has some sort of fuel issue. He explained to me that it will start up fine and run slow alright for 5 or 10 minutes but then would begin running rough and eventually stall out. However, if you ran it fast it will run fine all day, but as soon as you slow down to idle it would stall. After letting it sit for a few minutes or so, it would start up again but didnt want to idle.

So when i got it, I cleaned the carbs thoroughly (fairly built up with excess oil) and gave it a compression test (all near 120). Plugs were good and lots of spark. Installed it on the boat and it fired right up and ran smooth on muffs.

Launched the boat and it started fine at the dock, idled around for a bit, then exercised the throttle a bit and it was running very well. Threw a line out and started trolling and soon after it stalled. Got it started after a bit of cranking and the high idle on, but it didnt want to idle without the fast idle engaged. Managed to get moving again and opened it up and it ran flawless. Lost my hat so turned around to go rescue it and it stalled again. Never got it going again (or retreived my hat), returned on the kicker.

Fast forward after 3 days of sitting on the trailer, put the muffs on it turn the key and it sprung to life like nothing ever happened.

Does this sound like a fueling issue or electrical, or maybe a combination of both? I am trying to tackle this systematically so im wondering what the best place would be to start. Thanks in advance.

This is personal now since my favorite hat is now lost at sea...

Launch the boat.----Test run with cowling off.------Also test run with another fuel tank and hose.

Tried it with my kickers fuel tank and hose when it happened, no difference. Had the cowling off when trying to restart it as well.

Check your spark when trying to start. Should jump a 5/16" open air gap on a spark tester.

Boobie, I dont have a spark tester. Just grounded the plugs to the head and the spark seemed normal but i understand it is not an accurate way to measure it.

I did some resistance testing on the powerpack last night and all values are within range. Need to get a DVA adapter to test the running values however.

With the voltage regulator/rectifier unit, the 2 yellows and red all work properly supplying voltage only 1 way. Are all three supposed to have the same resistance as well? The 2 yellows are identical, but the red has almost zero resistance. Not sure if a bad rectifier could cause the issue im having.

I also noticed that my VRO pump is seeping gas out of the diaphragm housing if i pump it up with the ball. Perhaps it can be allowing air into the fuel circuit? I have a standard pump unit i can try to eliminate that as a culprit. I have the oil injection side isolated anyways as this boat does not have an oil tank. I am also going to replace all fuel lines with new while I am at it.

Going to try to work on it in the driveway a little bit tomorrow. Any other electrical tests i should try to aid in process of elimination?

I forgot another possible symptom, but not sure if it is normal on all outboards with power trim.

When idling on muffs, i noticed if the motor is trimmed all the way down, the idle is at its lowest. the more i trim it up, the idle increases along with it. Don't have my tachometer installed yet so unsure of actual RPM, but i would have to guess a range of 400 RPM maybe. Could this be the floats sticking/not seating causing overfueling?

Nothing wrong with it. Perfectly normal