Okay, let's clarify for you. You need both, but they are in different spots.


You need a 'fuel pump' from the fuel tank to the engine in order to keep the fuel line nice and pressurized so the engine isn't starved when its running at high power. Don't even bother asking if you need this ever again. The answer might as well always be 'YES!'. You ALWAYS need a fuel pump, or you're relying on the engine to somehow suck up fuel on its own, which leads to poor performance.

On the fuel tank, you have to imagine that as the fuel pump sucks the fuel out of the tank, it slowly becomes an empty vacuum, which after enough time, starts to work against the fuel pump itself until the back pressure is so high the pump cannot pull any more fuel, and the engine dies. Thus, for the fuel tank, you need the pressure relief valve to vent air from the outside to replace the fuel volume being sucked out.

I'm going to, with terrible ASCII text, show you what this kinda looks like.

[ENGINE]=========<[PUMP]<======[{LIQUID RELIEF VALVE{Fluid Port} FUEL TANK


FUEL TANK {FluidPort}{GAS RELIEF VALVE}]====|HULL|=={Any Fluid Port} \\OPEN AIR ABOVE WATER LINE\\

The Liquid Relief Valve only lets liquid through. The gas relief valve only lets air or gasses through. The arrangement I tried to illustrate above puts a liquid relief valve just after the port in the fuel tank so the pump doesn't pull air. While the gas relief valve only lets air in and out of the tank, and prevents fuel from leaking out.

Originally posted by AdmiralTigerclaw:

Okay, let's clarify for you. You need both, but they are in different spots.


You need a 'fuel pump' from the fuel tank to the engine in order to keep the fuel line nice and pressurized so the engine isn't starved when its running at high power. Don't even bother asking if you need this ever again. The answer might as well always be 'YES!'. You ALWAYS need a fuel pump, or you're relying on the engine to somehow suck up fuel on its own, which leads to poor performance.

On the fuel tank, you have to imagine that as the fuel pump sucks the fuel out of the tank, it slowly becomes an empty vacuum, which after enough time, starts to work against the fuel pump itself until the back pressure is so high the pump cannot pull any more fuel, and the engine dies. Thus, for the fuel tank, you need the pressure relief valve to vent air from the outside to replace the fuel volume being sucked out.

I'm going to, with terrible ASCII text, show you what this kinda looks like.

[ENGINE]=========<[PUMP]<======[{LIQUID RELIEF VALVE{Fluid Port} FUEL TANK


FUEL TANK {FluidPort}{GAS RELIEF VALVE}]====|HULL|=={Any Fluid Port} \\OPEN AIR ABOVE WATER LINE\\

The Liquid Relief Valve only lets liquid through. The gas relief valve only lets air or gasses through. The arrangement I tried to illustrate above puts a liquid relief valve just after the port in the fuel tank so the pump doesn't pull air. While the gas relief valve only lets air in and out of the tank, and prevents fuel from leaking out.

ok so i tried this with several pumps. even with impeller pumps that gives me over 40 l/s into my turbines it still stalls when fuel is low. at the moments i just have 4 large fluid pumps pumping air into the tank since that seems to work somewhat. Ive added additional ports for ventilation and even with 2 for each tank it still draws a vaccum

Maybe link your project

Originally posted by DrunkenTee:

Maybe link your project

im not going to release it to the workshop atm. :/

Originally posted by Ragoon:

Originally posted by DrunkenTee:

Maybe link your project

im not going to release it to the workshop atm. :/

Then we cant look at it and help you solve it. Good luck.

you don't have to release it to the workshop. Upload it and change the visibility as "unlisted". Then link it here for some help. Once you have it solved, delete the thread and the link to your unlisted project will be gone.

Bonus, you've backed up your build on the workshop instead of relying on your computer.

Originally posted by Booze_Rooster:

you don't have to release it to the workshop. Upload it and change the visibility as "unlisted". Then link it here for some help. Once you have it solved, delete the thread and the link to your unlisted project will be gone.

Bonus, you've backed up your build on the workshop instead of relying on your computer.

here is the ship, DO not save it due to it using other peoples microcontrollers. i might in the future make a more "polished version with all the permissions ;)

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=3402735618

Originally posted by Ragoon:

Originally posted by Booze_Rooster:

you don't have to release it to the workshop. Upload it and change the visibility as "unlisted". Then link it here for some help. Once you have it solved, delete the thread and the link to your unlisted project will be gone.

Bonus, you've backed up your build on the workshop instead of relying on your computer.

here is the ship, DO not save it due to it using other peoples microcontrollers. i might in the future make a more "polished version with all the permissions ;)

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=3402735618

Holy necro

Originally posted by DrunkenTee:

Originally posted by Ragoon:

here is the ship, DO not save it due to it using other peoples microcontrollers. i might in the future make a more "polished version with all the permissions ;)

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=3402735618

Holy necro

good luck ;) godspeed