[kriswd40]

Its carburated actually. I don't have any fuel pressure gauges, just oil pressure and that seems fine.

[kriswd40]

I couldn't find any loose connections. I replaced the fuel filter and replaced the ignition coil too (that seemed to be the other primary cause of issues similar to this that I found online). Ran the boat in my yard for 15 minutes without issues. I'm gonna try run it longer on Friday when i have more time and if that goes well, take it out on the lake. Running at idle in the driveway isn't really the same as running it under a load so I may be getting myself stuck out on the lake again this weekend but I'm not sure how else to really find out :/

[Brian Belcher]

Sounds like coil collapse to me. You can ohm across the "+" and "-". It should be .6 to .8 ohms. This is the primary circuit.
Next, ohm from the center, high voltage hole, back to the "+" on the primary side. It should be between 9400 to 11,700 ohms. This is testing the secondary side.
After you get your coil replaced, which I'm confident that that is your problem, start the motor and make sure the "+" to an engine ground is LESS than 8 volts. This is testing that the ballistic resistor is doing its job of greatly reducing voltage to coil while it's running. Straight battery voltage will run the engine great but it cuts the life of the significantly.
Does yours have the ignition module in the distributor? If so, pull it out and clean up the contacts.
Good luck

[sommerflying]

Thanks for the thread guys. I had a similar problem. I drained my tank, and then checked my fuel filter. See the attached pic. I believe I found the problem: water in the gas.

I believe the gas cap seal was rotten and/or the fuel vent did not have a "P" loop in it allowing water to get in the tank. New ones on order.

[kriswd40]

Thanks everyone!

I went out tubing, water skiing, and just cruising around all memorial day and didn't have any issues. I replaced both the fuel filter and the coil, but I think it was likely the coil that was the cause of my issues. I didn't think to check the voltage of the old coil before I threw it away, that would have told me for sure it sounds like.

I did the same thing checking my gas but I didn't have any water in it like that. Looks like you've found your problem and hopefully solution too!