Home page
SPONSOR AD

Topic: gas tank sediment

in Forum: C3 Fuel, Emission Control, and Exhaust Systems


gas tank sediment

Posted: 8/7/04 3:30pm Message 1 of 13
Former Member
Send PM
Miramar, FL - USA
Joined: 3/16/2004
Posts: 672
Vette(s): 1972 coupe/350 cid/mild cam/4 spd/20 ft. paint (looks perfect from 20 ft.), but it sure runs nice.
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. |laugh|


SPONSOR AD:: (Our Sponsors help support C3VR)

gas tank sediment

Posted: 8/7/04 5:51pm Message 2 of 13
Former Member
Send PM
sonoma, CA - USA
Joined: 8/9/2002
Posts: 784
Vette(s): 72 LT-1 AC coupe,69 l-36 coupe
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|



gas tank sediment

Posted: 8/7/04 6:34pm Message 3 of 13
Former Member
Send PM
Miramar, FL - USA
Joined: 3/16/2004
Posts: 672
Vette(s): 1972 coupe/350 cid/mild cam/4 spd/20 ft. paint (looks perfect from 20 ft.), but it sure runs nice.
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


gas tank sediment

Posted: 8/7/04 7:09pm Message 4 of 13
Former Member
Send PM
CONCORD, MA - USA
Joined: 6/12/2002
Posts: 185
Vette(s): 78 Silver Anniversary (2 Tone) L82 auto loaded
try a couple of cans of methonal dry gas. see if that helps.
Steve |wavey|


gas tank sediment

Posted: 8/7/04 7:47pm Message 5 of 13
Profile Pic
Lifetime MemberLifetime Member
Moderator
Send PM
CUYAHOGA FALLS, OH - USA
Joined: 12/2/2003
Posts: 6424
Vette(s): 1975 C3 Red, T-Tops, Black Interior. All I need is time and money! Getting there!
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.


gas tank sediment

Posted: 8/7/04 10:27pm Message 6 of 13
Former Member
Send PM
sonoma, CA - USA
Joined: 8/9/2002
Posts: 784
Vette(s): 72 LT-1 AC coupe,69 l-36 coupe
Your Welcome.


gas tank sediment

Posted: 8/8/04 2:34am Message 7 of 13
Former Member
Send PM
Miramar, FL - USA
Joined: 3/16/2004
Posts: 672
Vette(s): 1972 coupe/350 cid/mild cam/4 spd/20 ft. paint (looks perfect from 20 ft.), but it sure runs nice.
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?


gas tank sediment

Posted: 8/9/04 9:16am Message 8 of 13
Profile Pic
Lifetime MemberLifetime Member
Moderator
Send PM
CUYAHOGA FALLS, OH - USA
Joined: 12/2/2003
Posts: 6424
Vette(s): 1975 C3 Red, T-Tops, Black Interior. All I need is time and money! Getting there!
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.


gas tank sediment

Posted: 8/9/04 10:32am Message 9 of 13
Former Member
Send PM
Miramar, FL - USA
Joined: 3/16/2004
Posts: 672
Vette(s): 1972 coupe/350 cid/mild cam/4 spd/20 ft. paint (looks perfect from 20 ft.), but it sure runs nice.
Man, what I don't know about all this stuff is alot.

JR


gas tank sediment

Posted: 8/11/04 8:32pm Message 10 of 13
Former Member
Send PM
CONCORD, MA - USA
Joined: 6/12/2002
Posts: 185
Vette(s): 78 Silver Anniversary (2 Tone) L82 auto loaded
Hi Ken
You were right to correct me on this!
I shoud'nt respond these questions late at night.
Steve |wavey|


in Forum: C3 Fuel, Emission Control, and Exhaust Systems


SPONSOR AD: (Our Sponsors help support C3VR)