99 VP 5.7 GSI unknown fuel system problem

On our last trip out we were towing a tube and then the motor died. I went through the routine checklist and nothing worked. We were able to get a tow and made it home. Later I was doing some diagnostics and found that the fuel pump would not prime just when I turned the key. I pushed the reset on the fuel pump, nothing. Then I pushed it even harder and it clicked. Then I turned the key and the boat started right up. The next day I replaced the fuel filter and the motor started right away. After idling for a minute or so the engine began to seem as if it were straining. I checked the gauges and noticed my RPM's were reading around 3000 (but the engine was not reving as if it were at this RPM) and then the fuel tank gauge went from half a tank to zero. But I know that the tank if at half, no fuel leaks noted. Then I heard a loud whine coming from the rear of the motor, I listened closer and belive it was coming from the second (high pressure) fuel pump. The engine never stalled but the gauges were giving me these very weird readings. I did not know what to think so I shut the motor off and decided to seek help before I started it again.

Any ideas? Please.

Re: 99 VP 5.7 GSI unknown fuel system problem

Also, my low pressure fuel pump was very hot to the touch.

Re: 99 VP 5.7 GSI unknown fuel system problem

Sounds like you may have an air leak in your fuel system. Try this.

http://forums.iboats.com/showthread.php?t=167561

Re: 99 VP 5.7 GSI unknown fuel system problem

Yesterday I began the long process of checking the fuel system. I started at the tank and worked my way towards the motor. I checked the pick-up tube, tank to low press pump hose, filter, low press pump, and all the lines and fittings along the way. Not a single thing seemed to be the cause. Then I removed the high pressure pump and found that the rear (inlet) side had a worn out o-ring. Also found debris in the filter screen that looked like it came from the o-ring.

I'm thinking this may have caused my high pressure pump to draw in a small stream of air and make it whine. I'm gonna dig a little deeper and see if there's anything else. Regardless if that fixes the problem or not I'm still taking her in to be serviced. I've only had the boat for three years and don't have a clue about the prior upkeep.

Thanks for the input, I'll update on what happens next.

Re: 99 VP 5.7 GSI unknown fuel system problem

I'd Be Checking Elec Connections-start At Battery-eng Computers Do Not Tolerate Voltage Spikes Very Well.