700NXT's

[Fossil Fuel]

I'm having a hard restart after running all morning and sitting for a couple hrs. Cranks but no start, acts like a flooded old school carb.....?

 

[Wrinkleface]

vapor issue?????

 

[Raylar]

Any beeps from the Mercury guardian system? If yes, scan and look for codes, if not I would start with a fuel pressure check with key on and motor not running both cold and after sitting hot for a few hours and check results for differences. Sounds like a fuel issue if not an ecm guardian issue.

Best Regards,
Ray @ Raylar

 

[Chris]

they're very sensitive to air in the system. Hit the bleed valve and let it burp out.

 

[DollaBill]

I used to have the same problem with my 600's. Do what Chris said

 

[Fossil Fuel]

No issues appear in the VesselView. Both engines are doing the same. Where is the bleed valve ?

 

[Chris]

On the fuel rail- looks like a tire valve. We were out on Scism's 40 MTI yesterday and ran out of gas on one engine. They tried to restart it for about half an hour- Frankie showed up and popped the air out and 3 minutes later it coughed two times and fired.

If you put fuel in it up north anbd took it somewhere warm, it most likely vaporlocked. Summer fuels have more resistance to boiling.

 

[Ratickle]

On the fuel rail- looks like a tire valve. We were out on Scism's 40 MTI yesterday and ran out of gas on one engine. They tried to restart it for about half an hour- Frankie showed up and popped the air out and 3 minutes later it coughed two times and fired.

If you put fuel in it up north anbd took it somewhere warm, it most likely vaporlocked. Summer fuels have more resistance to boiling.

Nice to know...

I'll try to file that away just in case....

 

[MarylandMark]

We were out on Scism's 40 MTI yesterday

I'm sorry your life is so tough- can we send donations? :sifone:

 

[Fossil Fuel]

Dollabill, Did the issue on your 600's go away? Or do you have to bleed air each time. I have burned through about 1,000 gallons of 93 in Florida so whatever gas was in there from California is gone. Every time I make a lunch run to wherever after sitting for 1-2 hrs no restart. If I stop for 15 minutes no problem..mmmm

 

[DollaBill]

Was on and off. Seems to be an issue on all blue engines that are charged (600 - 1075/1200). I had the same thing happen to me with 1075's and lost 1/2 a poker run b/c I didn't know about the valve.

 

[Chris]

Here's how vaporlock occurs- when you shut a hot engine off on a hot day, the heat sticks around for a good long time. There's fuel left in your fuel rail and if it gets hot enough, it boils- and turns into a gas (not gasoline). Gasoline boils at a much lower temp than water- depending on the additive package it has in it. Summer fuels have particular additives that prevent this and winter fuels do not. Additives can be more expensive than the gasoline base stocks and there's no sense adding more than you need If it cools enough to condense back into liquid, your engine will typically restart. With modern high-pressure fuel systems, it's an unusual occurence. But it does happen. It's fairly common when you get those 80 degree days in April, before the summer gas hits the station tanks.


That sounds like heat soak on an electrical component is also a possibility. Another not-unusual occurrence. Heat can cause circuit component to expand and lose contact. When it cools and contracts, the circuit is closed. You can test by isolating particular components and either douse them with cold water or spray them with freeze spray.