Fuel tank replacement

[WoodenBirdOfPrey]

Shortly after purchase Virginia developed a fuel leak when the tank is more than half full.  It's coming from the top of the tank, so i'm pretty sure it's the o-ring at the sending unit.  Upon closer inspection of the tank, i also found which looks like a previous leak on the bottom of the tank that was patched up with some kind of black putty.  Being that's probably not a permanent fix, and that it's probably a sign that the tank is rusting inside, I'm going to replace the whole tank.

My first question is regarding the grommet around the filler neck.  I have no experience with fillers that attach to the tank like these.  Does anybody make new grommets?  What are the chances that I get a leak if I re-use the existing one which is probably original?  Is there some sort of fuel-resistant gasket maker I can use around the grommet to make sure it seals up good?

Second question, opinions on using the tank out of my 88 parts car vs. buying a new tank?  I think i'm going to drop the tank out of the parts car anyways to use the sending unit since the fuel gauge on Virginia jumps all over the scale constantly, mostly reading towards the high side.  Is it common for the tanks to rust out?  If it's a common thing, i'll just spend the $130 and order a new one from Rock Auto.

Any tips or tricks with dropping the tank out or anything else with this process?  Will I need any special tools?  I know they make a tool to remove the sending unit lock ring, would a pair of channel lock pliers get the job done?  I never replaced a fuel tank before so i'm not sure exactly what I might run into.  Is it best to take the fuel lines off before I drop the tank or after?

Thanks for any help.  I would really like to avoid having to redo my work due to mistakes, or turning my car into a molotov cocktail on wheels.

[captspillane]

Its very common for salt slurry to get stuck on the upper lip of the fuel tank. The plastic shield functions well to trap it there. Just about every PA car will need a new fuel tank. There isn't really an Oring on the sending unit and I've never encounterd a leak there. If its coming from the top of the tank it could also be the vent tube has rusted off. Once that rusts off you'll have a small hole on the top of your tank.

The huge round grommet at the back of the tank is not a usual problem spot either. I doubt you need to replace that or your filler tube. Its well worth the 130 dollars for a new tank but the first step is to to remove and inspect what you already have. Its likely that the parts car will be serviceable with a quality paint job.

A pair of channel locks will not work well on the lock ring. The trick is to use a punch and a hammer. If you tap on one side than the other it will eventually start to spin. Once its slightly loose you can push on both tabs at once with two big screwdrivers and it will spin off.

Make sure you take great care in saving the bolts that hang the tank. They easily break and I have never found a replacement for them. First pop the bolts behind the license plate and then twist the filler tube out. You don't need to seperate the filler tube and the license plate. Next disconnect all the fuel lines and the grounding wire before loosening the bolts.

While the tank is down its important to pop the fuel sending unit out. It has a mesh filter at the bottom of the pickup tube that has to be removed. It will be clogged after 20 some years of service. Don't bother replacing it inside the tank. A clear inline filter should be substituted directly outside of the tank.

[mudkicker715]

Threaded rod can be bent for the bolts that hang the gas tank.

[captspillane]

Threaded rod can be bent for the bolts that hang the gas tank.

I've done this once. It works but its crude. Jeep Cherokees also use the exact same bolt and I've always been in disbelief that I can't find a vendor who carries them. I've spent alot of time looking for one that does. Anyone else find new replacement bolts with the funky bent head on them?

[WoodenBirdOfPrey]

The thing that gets me here... the car with the leak is a Virginia vehicle, which is a generally rust free car, and shouldn't have seen any salt to sit on the top of the tank and rust it out.  That's the main reason I was thinking it was leaking around the sending unit.  I guess I'll find out when I drop the tank out.  Either way I think i'll just buy a new tank and know that I won't have to worry about anything rusting through as long as I'm going to own it.

Are there any good tricks to draining the fuel out of the tank before I drop it?  I think it's got about a third of a tank in it based on my highly unstable fuel gauge.  I would just drive it and use the fuel up, but with the cracked flex plate that's not much of an option.  I thought about just poking a hole in the bottom to catch the fuel since the tank is getting replaced anyways, but something tells me that will turn into a mild to moderately sized puddle of fuel on the floor of my garage by the time it's done with.

[WoodenBirdOfPrey]

Seems like a good way to burn up a starter. Not much of an option anyways as that's still going to put more undue stress on my crackplate which I think is just hanging by a thread.

I thought about trying to siphon it out but the mouthful of gas thing put me off of that idea. I might try to rig up an inline electric fuel pump from a friend's boat if he let's me use it.

[eagleman]

To siphon out the remaining fuel I believe I would go to any auto parts store and purchase a siphon kit. They are really cheap and do a super job.I purchased one at auto zone a couple of years ago for around ten bucks and can't believe just how many times I've needed it. Just last week I had to replace the fuel gauge on my zero turn lawn mower. The float part had came off the gauge part and had fallen into the tank so the fuel tank had to be removed and the remaining fuel had to be removed first.Got out the ole siphon and emptied in in just a few minutes.Sure beats sucking on a hose! No comments from you perverts either!lol Anyway a siphon kit is the way to go in my book.

[WoodenBirdOfPrey]

I'lll pick one of those up, I didn't know they sold kits for it.  Sounds like that would be the bee's knees.

[eagleman]

Trust me it will work like a charm!

[BenM]

I thought about trying to siphon it out but the mouthful of gas thing put me off of that idea. I might try to rig up an inline electric fuel pump from a friend's boat if he let's me use it.

I've done a few fuel tank drops. I finally broke down and bought an inline pump for about $35 after the cheap siphon I bought melted after a few gallons. I hooked it up to a lighter socket, plugged it in and now I have a reliable and easy way to transfer gas, much easier then a siphon and you can pump right into the container in your trunk if you want.

You can get the regular clear vinyl tubing, available at pet stores and home stores in many sizes. That's what most siphons supply. It's fuel-resistant but not heat resistant, which is why it's generally not used in engines. (Although I think that's some of the factory the tubing in my diesel Jetta...) Having plenty of tubing makes it easy to locate everything and not worry about tubes falling out, plus the clear tubing lets you see when you start sucking air.

An electric pump lets you get as much as possible out of the tank too, as it'll suck air. Although you're in for the socket plug, some wire, and some hose. Expect maybe $50 total.

[rohnk]

Sure beats sucking on a hose! No comments from you perverts either!lol Anyway a siphon kit is the way to go in my book.

 

[WoodenBirdOfPrey]

I'm in the process of siphoning the last bit of fuel out, sending unit wiring is disconnected, the plastic pan is off in the back, and the fuel lines are off.  I've had the hanger bolts soaking in PB Blaster and no luck so far getting them broke loose.  Normally I'd get the torch and heat them up, but with the whole thing about it being next to the fuel tank that leaks, i'm thinking that's unadvisable.  Anybody have any tricks to get them off without breaking them?

[mudkicker715]

Threaded rod can be bent for the bolts that hang the gas tank.

Break them and replace

[WoodenBirdOfPrey]

Well the whole point of not breaking them is they don't make/sell new ones.  I don't want to do a half butt rig job with threaded rod if it's possible to save the correct original hangers.  They don't look rusted bad at all because this car hasn't seen road salt, there's just 25 years of who knows what making it stubborn.

[mudkicker715]

Half assembly rig job. Nice. All depends on fabrication skill. I guess.
My thoughts are that eagle aged bolts such as that. Length, road grime, inabilty to heat, inches to turn. Good luck.

Clean the threads that are showing.