Bulb/fuel line issue….

[charlie_the_tuna]

I’m running home last week after a day of fishing and I’m at about 4,600rpm. The rpm’s drop a couple hundred and back up and back down and then drop all the way and shut down. It restarts right away and I bumped it back up and it happens again. So I figure let me check the bulb. Soft. I squeeze it hard and start back up. Runs fine for about 25 minutes and happens again. So I squeeze and head home and it runs fine.
I’m out today and it happens again. Same thing. I squeeze and it runs fine.
My plan is to run it best I can and address it when I’m out after the season. I’ll replace the fuel line from tank to motor.
I haven’t done any required maintenance yet. My plan was to do all maintenance after the season.
What could be the cause of something like this? Will replacing the fuel line fix the problem?
Spare?

[spareparts]

Is the bulb sucking flat? If the engine is pumping fuel, the bulb isn't going to be tight, the fuel pump is pulling a vacuum on it sucking fuel to the engine. Make sure not to use an aftermarket primer bulb. I use the mercury bulbs. If your fuel lines are over 10 years old, replace them

[charlie_the_tuna]

Not sucking the bulb flat. Just losing it’s firmness. I imagine the lines are original. It’s not the prettiest. I’m gonna change it all when we come out of the water. Worst case, I squeeze the bulb every half hour or so. Haven’t done the filter/water separator. Also on my to do list over the winter.

[charlie_the_tuna]

I’m assuming they’re all 3/8”. This one is thick. Heavy walls. Only 4 feet or so. Should be an easy job.

[spareparts]

A1 fuel line below deck, you can use B1 fuel line above deck. the primer bulb will not stay firm under use, you have to pump it up(create pressure in teh line ) for it to be firm, once the engine draws fuel it will not be firm. Check your anti siphon valve in the fuel tank, Id bet its corroded al to crap and about to break off

[charlie_the_tuna]

Anti siphon valve is the fitting the fuel line is connected to? The little elbow coming out of the tank?

[spareparts]

yes

[charlie_the_tuna]

We are currently limping home at about 3.5 mph. The issue is now almost continuous. When we pump the bulb it stays flat for like a minute and takes forever to pump it hard. When we do, we run it up to about 4,000rpm and almost immediately it starts to shut down. It doesn’t shut off but the rpm’s drop to under 1,000 and we’re running home at less than 5mph. Should take us another hour or so to travel the 4 miles back to the dock.
HELP!!!!

[charlie_the_tuna]

On the bright side, I’m 100% sure it’s not the motor.
Another plus, my boy landed a real nice fluke and we came upon a bluefish blitz. Every cast brought another two pounder aboard using 3,000 class spinning gear.
So there’s that.

[phatdaddy]

Take fuel fill cap off, see if that makes a difference