Water in fuel? Draining water separator?

[Ronmar]

Do the liquids flow out freely? When I open mine, some seems to drain out and then it stops because no air can get in. In order to drain the rest, I have to unscrew the knob a lot, until air can sneak in past the threads. Is that how it's designed to work?

No, you have to pump the water and fuel out with the primer. If you look at the stainless ring around the primer bulb, there are instructions printed there.

Opening the drain is also a way to check if your flapper bypass check valve above the filter(underside of filter boss) is sealing. If you open the drain and it sucks air back into the drain, that is caused by gravity pulling fuel back down the supply line to the tank thru that leaking flapper valve above the filter...

 

[Awesomeness]

No, you have to pump the water and fuel out with the primer. If you look at the stainless ring around the primer bulb, there are instructions printed there.

Opening the drain is also a way to check if your flapper bypass check valve above the filter(underside of filter boss) is sealing. If you open the drain and it sucks air back into the drain, that is caused by gravity pulling fuel back down the supply line to the tank thru that leaking flapper valve above the filter...

Thanks. I did end up using the primer pump button, but didn't think that was right. That's what I get for doing it in the dark.

For those that want to see, here is a picture of the instructions on the pump button.

 

[Ronmar]

Thanks. I did end up using the primer pump button, but didn't think that was right. That's what I get for doing it in the dark.

For those that want to see, here is a picture of the instructions on the pump button.

Yep, except ours don’t have the vent screw/bolt seen to the right of the primer ring and mentioned in the instructions...

 

[Guyfang]

No, that's not how its supposed to work. I always drained mine just before turning off the truck. Then the system is under pressure.

 

[Awesomeness]

No, that's not how its supposed to work. I always drained mine just before turning off the truck. Then the system is under pressure.

How would the system be under pressure? On these engines the injectors are the fuel pumps... they draw fuel to the engine from the tank. The lines aren't pressurized.

 

[coachgeo]

How would the system be under pressure? On these engines the injectors are the fuel pumps... they draw fuel to the engine from the tank. The lines aren't pressurized.

Sounds like another reason to put in a "Temporary Service Only" aux. Elec. fuel pump back by the tanks. Pushing fuel to the engine .....
. helps you limp by on your journey if you get an air leak...... till you are at a better place to service it.
. helps with air leak diagnosis.... pushing fuel OUT of the leak area (usually; not always) so you can find them easier,
. helps prime the system
. can help push water out of the water bowl of fuel filter too apparently ?

 

[Awesomeness]

Sounds like another reason to put in a "Temporary Service Only" aux. Elec. fuel pump back by the tanks. Pushing fuel to the engine .....
. helps you limp by on your journey if you get an air leak...... till you are at a better place to service it.
. helps with air leak diagnosis.... pushing fuel OUT of the leak area (usually; not always) so you can find them easier,
. helps prime the system
. can help push water out of the water bowl of fuel filter too apparently ?

That sounds like a complex solution to a simple and unlikely problem. I would carry a spare fuel line (all 3 are the same fittings, so make one to match the longest) before I would go installing pumps.

 

[coachgeo]

That sounds like a complex solution to a simple and unlikely problem. I would carry a spare fuel line (all 3 are the same fittings, so make one to match the longest) before I would go installing pumps.

except that will not help you find what line is leaking...... nor allow you to limp to a better install location; or limp along in fowl weather till better repair day.

 

[Awesomeness]

except that will not help you find what line is leaking...... nor allow you to limp to a better install location; or limp along in fowl weather till better repair day.

The redundancy argument is a never ending one. Yes, you could just carry two of everything... except that you can't. So, personally, I want multi function tools that I can use to solve a multitude of problems.

 

[Ronmar]

No, that's not how its supposed to work. I always drained mine just before turning off the truck. Then the system is under pressure.

That primary filter assembly is on the suction side of the lift pump, it is never under pressure... you must pump,the fuel/water out...

 

[Guyfang]

Learn something every day. Generator fuel systems are under pressure.