Engine / Fuel problems

[pss3757]

My boat is a 2000 Outback LS, 5.7 L EFI , 442 hours. All has been pretty good for the 10 years I've had it. I would like to think I'm very skilled / mechanically inclined with inboard ski boats, I've had a few and perform most, if not all, maintenance and repairs myself.

Last week I went out for an hour ride and had some issues on the way back. The big fuel pump was humming louder than usual.
After running at about half throttle for an hour, I was on my way back to the dock and it started to cut out on me...like I was out of gas. Since the gas gauge is all over the place, as usual and doesn't give an accurate reading anyway, I slowed it down to 10-15 mph to conserve what little gas (I thought) so I could make it back. Could not remember exactly when I last filled it completely. After a few hundred yards, it really started to run rough and soon after killed...And would not restart. It did have a couple small backfires too. Thankfully I was in site of the dock and just pulled it in with my jet ski.

When I got a chance, I filled it with gas to full, but it would only hold 18 gallons, which meant I still had 9 gallons in the tank when it killed ( holds 27 gals), I also changed the fuel filter, it had been a couple years.

I routinely add stabilizer / ethanol shield in the gas....

Then it initially started right up, but died after 10 seconds or so, then it would not restart after Several tries. i loosened the nut to ensure i was getting fuel through the pump. On the next try it started right up and ran smooth at idle. Let it run 20 minutes and all was good. The big fuel pump seems to buzz normal. But it presently it seems to run okay...but almost dies when I initially put it in reverse, have to let it "warm up".

Any idea of the problem, I hate fixing something not knowing what is/was the cause?
I changed the spark plugs about 2 years ago, but not the wires. Think I need new wires?? Fuel pumps going bad?
Are there two fuel pumps, I see a small one about he size of your fist and another big blocky pump the connects to the main fuel filter??

Any thoughts or experiences?

[maxpower220]

My initial thought is that you fuel pump is going out. I would get a fuel pressure gauge and check the pressures that you are getting. Search the Indmar site or google for the specific pressure that you should be getting.

Just because of the age of the boat, I would inspect/replace the plugs, wire, cap, and rotor. However, I don't think those are directly related to your issue.

[Muzzy]

Sounds similar to an issue I had last year with my 06 LS, loud fuel pump whine, it would backfire, couldn’t get it over 10mph, and would die on me. I pulled the fuel pump out and in the inlet there is a little screen filter. I pulled it out with a pick and it was clogged with little pieces of rubber, my fuel lines were deteriorating and flaking apart. Cleared the little filter, replaced the fuel lines and runs perfect ever since. Not sure your 2000 has the screen filter in the fuel pump inlet, but worth 15 minutes to pull it out and check.

[pss3757]

I am thinking clog in low pressure fuel pump as a cause. I have seen indmar put out a bulletin on cleaning of the hvlp carter fuel pump....is this similar to what you did. I will also check fuel pressures and prob change plugs, wires, distrib cap etc at end of season....thanks for the replies