In-Tank Pump Sounds Like Leafblower

[JerrySab]

What's up fam!

Recently did a ton of work to old Goldie, and SURPRISE SURPRISE she's making weird noises.

I managed to track down an actual Motorcraft in-tank fuel pump, and replaced the frustratingly inaccurate off-brand knockoff version. Also replaced fuel filter and did some rust fix inside the tank. Everything was going great! UNTIL.. Last week I'm driving home and I hear what sounds like a leaf blower or a huge semi in low gear. I assume its either of those things and ignore it, until I realize it's coming from MY tank. This noise comes and goes now.

I haven't had a chance to lift the bed to inspect yet. But wondered what the general consensus would be on this. Is the pump dying already? If the rubber gasket slipped, would this sound be prominent, akin to a vacuum leak? Could the sock be blocked by.. I don't know what because I JUST CLEANED THE FREAKIN TANK. Did I put the fuel pump in the wrong way?

Would love your thoughts, but will try to pull the bed this weekend to see what's going on.

 

[franklin2]

I would be curious to know what the "rust fix inside the tank" was? Did you paint something inside the tank?

 

[JerrySab]

At risk of outing myself as a hack:

There was a decent sized patch of surface rust that, thankfully, didn't go very deep. I dropped the tank, emptied it, sprayed wd-40 brand penetrant on the corroded surfaces, then cleaned/sanded with steel wool on the end of a stick. rinsed with some leftover seafoam, wiped clean and let dry for about a week (I was repainting the truck so there was no rush to reinstall).

 

[franklin2]

I was just making sure you didn't put some sort of coating in there that had come loose and was clogging the pump. I would get another pump and be ready to change it out. Or keep the pump/sending unit you have now since you like how the gauge works with it, and put the other pump onto this sending unit, taking it's pump off.

 

[JerrySab]

Thanks Franklin! So I think I may have found it. The filler hose didn’t seem to be attached very well, and I’m wondering if it was letting some air into the tank. Filter sock was clear. Fuel lines are firm. No funny business with any wiring. Will kee y’all posted.