1995 Ski Nautique GT40 not getting fuel; fuel pump questions

[chilliwacko]

Last week the boat was running great, this week it wouldn't start. When I first turn the key, I can hear a pump buzz for a couple seconds. I popped off the air filter and the injectors weren't spraying fuel, but it felt like they were trying to inject. I'm pretty sure it's the fuel pump.

Thinking the pump was unable to prime the system, my friend and I tried blowing into the gas tank vent to manually pressurize the system. Ta-da! It started. However, once we turned it off and tried to restart, same problem. Blowing into the vent again got it started.

So my question: which fuel pump is likely at fault? And where on earth do I find part numbers for these pumps? I found a single part number in the GT40 engine manual for a fuel pump, 9A407, but it doesn't say if it's the low or high pressure pump.

Thanks in advance!

[DanielC]

Here is my standard thread about checking the fuel pressure, and the fuel pumps.
http://www.planetnautique.com/vb3/sh...=fuel+pressure
Post #8 in that thread has info on low pressure pump specs.

[chilliwacko]

Thanks Daniel. I'm itching to get out on the lake, so I might just replace both pumps while I'm at it rather than buy an inline fuel pressure gauge, check pressure before/after pumps, etc. I managed to find the part numbers by visually matching my pumps to pictures on nautiqueparts.com. For future reference, the 1995 Ski Nautique with GT40 needed the following:

RA080018 - Big silver low-pressure pump
RA080022 - Little black high-pressure pump