Surging Issues
 

Hey guys, I have an '05 24V with the Black Scorpion motor. Last weekend while surfing, the boat started surging, as if it was starving for fuel, or even water in the gas. I changed the fuel filter, and the water separator, and purged the air line from the schraeder valve, and added a water evaporator to the fuel tank. Today, I went out and ran fine for a bit, then started surging again. Funny thing is that it only happens while in gear. Revs up fine in nutral. At one point, I couldnt get passed 12 mph for a while, but had surges of wanting to go faster.
Any ideas ?

Change the distributor cap.

Sounds like fuel pump to me... Check your rail fuel pressure..

Tranny issue? How does it do in weighted?

Un weighted

Still sounds like a fuel issue to me.
I would look into draining the tank and filling with new gas. Could be bad gas too, ran into a similar issue years ago that ended up being bad gas.
Filled up at another station and it was fine. Filled up at that station and it sucked. Cars would run great on it, boat would not.

Not sure if it would be the fuel pump. When I rev the engine while in neutral, it sounds smooth, and fine.
The surging continued both weighted, and all ballast empty.
Just topped off the tranny fluid a couple months ago.
Can fouled plugs be an issue? Or maybe vaccuum ?

At a minimum, pull your distributor cap and see if it is coated with green icicles. If it is, replace it. If not, move on to next items.

My 02 supra was doing this before selling it, I checked the distributor cap and it was in bad shape so I replaced that and the rotor, all plugs and wires and a new ignition coil. It was time to replace all of that any ways but it didnt fix the problem, the problem ended up being the fuel pump. Surging is a pretty common sign for a bad fuel pump, it's not the only thing that can cause surging but its definitely worth a look.

I had the exact same problem with my Nautique the other week. I brought it in thinking forsure it was fuel related. It ended up just needing a full tune up.

I had the exact same problem with my 09 Axis A22 just 2 weeks ago. Put some fuel stabilizer in it because I thought it was the fuel. That didn't help at all, so we changed the distributor cap and it works like a new one.

At least check the distributor cap, if not change it. They aren't that expensive.

Looks as tho the Distributor cap will be next (and cheapest) to change. Ill try that one this week and let you know how it worked. Thanks for all the insight !!