71 tank question
Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 1,036
Likes: 2
From: Huntingburg Indiana
71 tank question
I had some trouble awhile back with water getting in the gas tank. I installed a new cap and cleaned out the drain hose. I found more water in it yesterday. What else could be the problem? Who makes the nicest American made gas tank? I would like to drop the tank to see if the build sheet is there anyway. Thanks a lot.
Marty
Marty
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Two things that I can think of.... 1) your gas cap is not a sealed cap and rain/wash water found a way to get in under it; 2) there's a collection of water in the gas supply tank at the station where you are buying your gas. Next time you fill up, take a quart jar with you and fill it first--then your tank. Let it settle and see if any water collects at the bottom of the jar. If so, show the manager; then have him give you some FREE bottles of HEET (basically alcohol which will mix the water in with the gas and cycle it through the engine with no problem) to clear the water from your tank. If neither of those...I don't get the "gold star".
Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 1,036
Likes: 2
From: Huntingburg Indiana
I have a new, non-vented GM cap on it. After I got the water out last time, it was fine. The car sat a little while due to cold weather and a bad battery. I put in a new battery and started it. It ran until the front bowl filled with water. I'm baffled.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
If the tank is rusty on top then you need a tank. Does the water seem to get there after it rains or you wash the car? Do you see any puddles of water under the filler door? Are you leaving it with the tank full or empty? Temperature changes could cause condensation in the tank.
The boot around the cap could be holding water and dumping it into the tank. The sending unit could be leaking too, but I'd think the amount of waer that could get in that way would be miniscule.
The boot around the cap could be holding water and dumping it into the tank. The sending unit could be leaking too, but I'd think the amount of waer that could get in that way would be miniscule.
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Melting Slicks
Joined: May 1999
Posts: 2,897
Likes: 0
From: Moon Township PA
Quanta Products at
http://www.quantaproducts.com/products.asp?dept=260
makes the repro tanks using original tooling.
http://www.quantaproducts.com/products.asp?dept=260
makes the repro tanks using original tooling.
Racer
Joined: Oct 2006
Posts: 293
Likes: 0
From: Colorado Springs Colorado
A few things it could be:
1. The cap (no seal/bad seal)
2. Bad gas from the filling station
3. A hole somewhere in the tank
4. The car has sat all winter/or sits mostly and condensation has built up.
At a minumum I would drain the the tank. All you have to do is get a mower can and disconnect the hose on the bottom of the tank and be ready...
Refill the tank and add a fuel system treatment. I had to replace the gasket on my cap and no more problems.
If that doesnt fix it, tanks are relatively cheap and arent hard to install. You can spend a bunch of nice sunny days trouble shooting that old tank...marginal benefit analysis says the best thing to do is replace the 30+yr old tank in one afternoon and enjoy the sunny days!
Cheers,
Crunch
1. The cap (no seal/bad seal)
2. Bad gas from the filling station
3. A hole somewhere in the tank
4. The car has sat all winter/or sits mostly and condensation has built up.
At a minumum I would drain the the tank. All you have to do is get a mower can and disconnect the hose on the bottom of the tank and be ready...
Refill the tank and add a fuel system treatment. I had to replace the gasket on my cap and no more problems.
If that doesnt fix it, tanks are relatively cheap and arent hard to install. You can spend a bunch of nice sunny days trouble shooting that old tank...marginal benefit analysis says the best thing to do is replace the 30+yr old tank in one afternoon and enjoy the sunny days!
Cheers,
Crunch
Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 1,036
Likes: 2
From: Huntingburg Indiana
I appreciate all the help, guys. I siphoned the tank today and 1 to
1 1/2 gallons of water came out. That's too much to be condensation. I will drop the tank and check for holes and make sure the gasket is OK. I would like to see if the build sheet is there anyway. I believe the water is from the rain. Like I said, I cleaned out the drain hose and put on a new cap. I don't believe it's from the gas station, because I fill my truck at the same stations and never have trouble. Again, thanks a lot for the help.
1 1/2 gallons of water came out. That's too much to be condensation. I will drop the tank and check for holes and make sure the gasket is OK. I would like to see if the build sheet is there anyway. I believe the water is from the rain. Like I said, I cleaned out the drain hose and put on a new cap. I don't believe it's from the gas station, because I fill my truck at the same stations and never have trouble. Again, thanks a lot for the help.
Intermediate
Joined: Mar 2004
Posts: 48
Likes: 0
From: Houston TX
I dropped my tank because of probs with water and rust,
I found it had no gasket between fillerneck and tank at all , seems like they forgot it from the factory !!!!!
,,open door for rain water basically
I found it had no gasket between fillerneck and tank at all , seems like they forgot it from the factory !!!!!
,,open door for rain water basically
Melting Slicks
Joined: Aug 1999
Posts: 3,123
Likes: 13
From: Hollywood, Florida
I appreciate all the help, guys. I siphoned the tank today and 1 to
1 1/2 gallons of water came out. That's too much to be condensation. I will drop the tank and check for holes and make sure the gasket is OK. I would like to see if the build sheet is there anyway. I believe the water is from the rain. Like I said, I cleaned out the drain hose and put on a new cap. I don't believe it's from the gas station, because I fill my truck at the same stations and never have trouble. Again, thanks a lot for the help.
1 1/2 gallons of water came out. That's too much to be condensation. I will drop the tank and check for holes and make sure the gasket is OK. I would like to see if the build sheet is there anyway. I believe the water is from the rain. Like I said, I cleaned out the drain hose and put on a new cap. I don't believe it's from the gas station, because I fill my truck at the same stations and never have trouble. Again, thanks a lot for the help.
the rubber hoses mounted to it. it is mounted on the upper left side of the tank. I almost broke mine when I removed the tank on my '71.