F3990 Fuel Sender

[4thGenOwner]

Hello All:
My 2016 F3990 fuel gauge level on the LCD cluster never moves. I am willing to drop the tank and repair or replace the sending unit, but my WSM service manual is devoid of any instructions on how to remove the tank. I have a pretty good idea on how I would remove the tank. But before I get started, I would appreciate any input from someone who has done that and successfully replaced the tank back into place. Or if the sending unit can be replaced with the tank in place, please inform me. I think dropping the tank would be best, since the tank might need a good cleaning at the floor of the tank. Please comment.

 

[MOOTS]

This is a 2690. Lots of stuff has to come off to remove tank. You can just see the sending unit at front of tank in picture.

 

[4thGenOwner]

View attachment 172643
This is a 2690. Lots of stuff has to come off to remove tank. You can just see the sending unit at front of tank in picture.

I see. Thank you for posting the photo, it's very helpful to see the scope of this procedure. I don't know if I am willing to go that deep into it. I suppose that to just change out the fuel level sending unit, the tank must be removed? Or can the fuel level sending unit be swapped out with the fuel tank simply loosened, but not fully removed?

 

[MOOTS]

It’s been awhile since I’ve done it. I don’t think there is room with the floor board covering the tank, to get in there and work. It’s really not a bad teardown. Rops is 2 or 4 bolts, seat is 4, handles from levers and like 6 bolts holding the floor pan down.

 

[4thGenOwner]

Yes, I looked at the floorboard assembly and the ROPS and seat fasteners, like you mentioned. After a little thought, I just decided to put it all back together. I'm backing away from the teardown until winter or whenever I really must get down into it that far. But for now, the only problem with my F3990 is the sending unit. I will just top off the fuel tank before mowing, making sure to not run it low on diesel fuel. Thanks again for posting the photo, I saved it for future reference. My WSM service manual was not much help on this procedure at all, but your photo was helpful!