97' GT40 Motor Stops Abruptly During Start - especially in colder temps??

[86silvernautique]

97' Ski Nautique - GT40 Motor

*It only happens first thing in the morning when it is colder outside. When I come back to the boat at 11a or later (slightly warmer) it's starts right up and runs just fine??

Ignition turns on
Everything lights up
Engine gets fuel and turns over very easily
Then the engine abruptly cuts of in under 2 seconds

Replace fuel pump relay switch, did not correct

Any ideas??
( I have video to share if that would help)

[bturner]

I did a bit of searching on this and there seems to be a few posts on the low presure fuel pump. This is what Brave AI had to say about it.....

Owners have reported reliable performance, with one user noting the engine runs at about 5400 RPM at wide open throttle (WOT), although continuous cruise RPM is typically limited to 4,000–4,200. The engine is also noted for being relatively easy to work on and dependable. Common issues include problems with the low-pressure fuel pump and small fuel hoses inside the fuel control cell (FCC) housing, which can develop cracks and cause starting or running issues; replacing these hoses is recommended during maintenance.

And what Google AI had to say.....

A 1997 Ski Nautique's GT40 engine that starts and then stops is most likely experiencing a fuel pressure or spark issue, often caused by the low-pressure fuel pump (LPFP) or one of the fuel pump relays failing. To diagnose, check for power to the LPFP and confirm it's pumping fuel, test fuel pressure with a gauge, and inspect the fuel system for clogged filters or a cracked hose to the fuel separator.

Those 2 items (low fuel pump and the relays) are in almost all the hits. I don't like firing the parts cannon often but when I do I like doing things like relays as they're cheap and easy to replace.