2000 BF130 spluttering and dropping revs

Hi,
I bought a Prosports with a 2000 BF130 last year. The boat ran fine last season.

Since I commissioned the boat for this season, my BF130 occasionally splutters when in gear and will not increase revs until mostly either I shift back to neutral a few times and/or turn it off and restart, although sometimes it comes good by itself.
Occasionally when I hit a wave, the revs drop right off, but then come straight back.
Last weekend when towing a tube, I couldn't get past 13kts at 4000rpm - it will normally sit at about 20kts at 4000rpm.
It smells like its running rich.

I filled the tank and added stabiliser for the winter.
Ive changed plugs to the good NGKs.
Changed the external fuel water separator.
Changed the LP fuel filter (first one inside the engine cowling)
Today I added Startron to the tank, changed the high pressure filter, emptied the onboard separator, changed the inline filter (the vertical one aft of the VST.
When I changed the high pressure filter (part 16911-ZY3-010) the one that was in there was bent in the middle - not sure what happened there!

Not sure where to go from here. When it runs, it generally runs great - I get 30kts out of it with my Prosports 2200WA. It starts first go every time without priming the bulb, there are no spluttering issues in neutral - if it is spluttering I can put it in neutral and it revs smoothly), and it idles fine.

Thanks,
Glen

I don't know much of anything about the BF130, but check out the simple things first. From your general description, it sounds like you are having a fuel flow problem. When it sputters, feel the primer bulb to see if it may be partially collapsed. If so, you have a clogged breather vent on your fuel tank or a clogged pick up tube in your tank. Open up the fuel tank filler tube to see if that clears up the problem. If so, you have a clogged vent.

When it starts to sputter, pump the primer bulb and see if that clears it up. If so, you could have air in the fuel line or a failing low pressure fuel pump.

Thanks CHawk - I'll do the breather vent/pickup tube tonight, and drain the VST. When it happened last time, the bulb hadn't collapsed but wasn't hard either. Priming it didn't fix the spluttering. I'll have the boat in again on the weekend, so we'll see what happens.

The primer bulb is a bit soft when the engine is running - not real spongy, but soft.

So I checked the PCV and hose and ran the engine. The pump cover from the high pressure fuel pump, where the strainer filter (part 38 in every other forum post) goes is leaking at idle, due to a crack in the lip of the cover, so parts now on order. Its not a massive leak, but its a leak, and might be a contributor. Other than that, the motor sounded good and no other leaks obvious. I primed the bulb before I started the engine - the bulb never went hard.