gas tank sediment

Recently, I uncapped my tank and with a flashlight, discovered this reddish-colored sediment neatly piled in those little valleys at the bottom. By the looks of the strainer (same color), I'm sure it doesn't stay down there all the time, probably sloshing around every curve I take. Could it be rust or red dirt? There's no red dirt down here, but this Vette resided most of it's life in Central Florida where it most likely got it. The gas cap is stamped VENTED...I can't imagine it getting in there any other way. Are there any contraindications to switching to an UNVENTED cap?

JR

P.S. In order to remove strainer, does the sending unit have to come out? Lazyman's way will do just fine, thank you.

haha, that "red dirt" that you speak of is rust, just replaced my tank and strainer for the same reason, when I looked inside the tank with a flash lite it didn't look to bad but when I took a small adjustable- extendable shop mirror and stuck it inside the tank and looked at the bottom side of the top of the tank it was rusting away, with the tank not full of gas condinsation hangs from the top of the tank, if the car is not driven much it will rust through the protective coating over the years, its like cancer, when it goes through the coating you can't stop it, boiling will clean it for a short time but it comes back, when you replace the tank and strainer make sure to disconnect lines at fuel pump and blow the lines, replace fuel filters, I don't recomend switching the cap,it't not the cap, the strainer just pushes on and off, check the inside bottom of the top of the tank,I think its time to pull it.

|UPDATED|8/7/2004 5:51:03 PM (AZT)|/UPDATED|

All this time, the rust issue was on my mind. This will be the third tank for this car. The previous had the car three years and said he replaced it midway thru his tenure. You're absolutely right about the condesation. Thank you for your well detailed answer.

JR

try a couple of cans of methonal dry gas. see if that helps.
Steve

You do have to pull the sending unit out to change the screen. The bad news is you will probably need to pull the tank to get rid of the rust in the tank.

If the car was designed for a vented cap, that means there is no other gas tank vent. Replacing with a non-vented cap will create a vacuum in the tank while driving, and cause fuel starvation. Sitting in the sun the tank could expand and cause flooding. Use the vented cap.

Your Welcome.

I'm not beating-around-the-bush with this, it's only gonna get worse, so I'm pulling it. I didn't mention this before but there's rust on the cap and I should've suspected it when I saw that. Oh well, perfect opportunity to see if the build sheet was put back after the last time the tank was replaced, been wondering about that. Thank you, all and have a good what's left of the weekend.

JR

BTW, Steve, is methanol dry gas another term for gasohol?

Methonal or Ethonal can be used in Gasohol. Neither will remove rust or dirt.

Dry gas can be Methonal or Iso-propol.
Methonal seperates water from gas, but leaves it in the bottom of the tank. Iso suspends it in tiny drops and allows it to go through the fuel system and out.

Man, what I don't know about all this stuff is alot.

JR

Hi Ken
You were right to correct me on this!
I shoud'nt respond these questions late at night.
Steve