disconnected plug at water/fuel separator

[dennisuello]

I was changing the fuel filters yesterday and noticed that on of the electrical plugs was disconnected from the fuel/water separator. I just bought the truck, so maybe previous owner disconnected it. It's the one circled in red on the picture. What's this plug for?

I have not re-connected it yet, as I wanted to make sure it wasn't done on purpose, as there are no codes and the truck runs great.

[amdriven2liv]

Does this help?

[dennisuello]

Yes, it does help. It's the water in fuel sensor wire. Why would anyone disconnect it? Unless the sensor is bad and they wanted to get rid of the dash light. I guess, I will reconnect it and see what's going on.

[amdriven2liv]

When you did your fuel filter, did you drain the water?

That drain plug tends to strip.

I suggest you get one of these:

DTS Articles - HFCM Water Separator Drain Plug Upgrade

Easier to use, and make less mess, because the fuel will flow out more in a controllable direction.

[dennisuello]

Originally Posted by amdriven2liv

When you did your fuel filter, did you drain the water?

That drain plug tends to strip.

I suggest you get one of these:

DTS Articles - HFCM Water Separator Drain Plug Upgrade

Easier to use, and make less mess, because the fuel will flow out more in a controllable direction.

Ordered one of those already. Part of the stock plug was missing, looked like it corroded off.

[DieselDano]

Not sure which plug you are saying wasn't connected, but I have seen a lot of trucks that came factory with the heater element in the separator having been replaced with a part that did not have a heater installed, so the plug just did not have anything to connect to.

The water in fuel sensor is kind of tubular, with the contacts about 1/4 away from the aluminum housing itself. Lots of times algae grows inside there and even after you drain the separator, that gunk is still on the sensor and the light will continue to say that there is water in there, when there isn't.

Did you try to reconnect that plug? I am curious if your water in fuel light comes on when you plug it up. Thinking the previous owner disconnected it because the light wouldn't go away. If your light does come on, I would remove the outer housing with the fuel lines attached to it. You may find a lot of gunk in that bottom cavity, I always used a fresh can of brake cleaner and sprayed it into that sensor to blow the debris off of the contacts. Usually the rubber gasket behind there swells, and is very difficult to reinstall. Just use a fair amount of grease or vasoline to make the gasket stick to the housing and reinstall the outer plate.

The sensor is supposedly also removable, but I only ever broke them when I tried to remove them.

One more thing to keep in mind, in the picture above shown as picture 56. That black piece sometimes tries to come out when you remove the outer housing, as there is a spring under it. Just be careful and pay attention when you remove the outer housing.

[94slowbra]

thats for the water in fuel light on the dash to indicate when you have water in the fuel. they might have unplugged it because they had water in the fuel and didnt want a light. if i were you i would drain it and take the entire assembly apart to make sure its all clean. i have seen some of these separators full of junk from not draining them when they needed it. maybe nothing but better safe than sorry