<VV> Gas Tank

[FrankCB at aol.com]

Yes, probably more gas tanks rust out from the  INSIDE than do from the 
OUTSIDE.  It's not that the gas you buy has water  in it (at least not usually) but 
the fact is that the Corvair gas tank BREATHES  through the vented gas cap.  
So as the day cools off into evening, the air  pressure in the tank drops and 
moist air is sucked into the tank.  Further  cooling of this air in the tank 
causes the humidity to reach 100% and moisture  condenses out of the air and 
falls into the gas.  Being heavier than the  gas, the condensed water falls to 
the bottom of the tank and if left there will  eventually rust through the 
bottom of the tank.
    Short of keeping your Corvair in a humidity  controlled environment, what 
you have to do to prevent this is to periodically  add "drygas" to the gas in 
the tank.  This alcohol causes the water  condensate to DISSOLVE in the 
gas/alcohol mix and be distributed  evenly throughout the gas in the tank where it 
will do no harm.  While you  can use methanol based "drygas", the isopropanol 
version is much more effective  even though it does cost a bit more.  In 
northern NJ I use "Iso-Dry".   Read the label to tell if it contains methanol or 
isopropanol.  Try it  unless you enjoy replacing/repairing leaky gas tanks.<GGGG>
    Frank "alcohol has many uses"  Burkhard    
 
 
In a message dated 11/17/2006 9:23:56 AM Eastern Standard Time,  
kaczmarek at charter.net writes:

----  Brandon Muzzin <overkill11111 at hotmail.com> wrote: 
> Hello  everyone,
> 
> I have a 66' Monza coupe that I'm working on, I was  wondering if it were 
> possible for the gas tank to rust from the  inside out?

Brandon
They can, and they do. Last one I saw was in my  friend Erics' 64. he noticed 
that the outside of the tank was damp, and the  car had been in the garage 
for a couple of weeks, no way any water was getting  inside the garage.  

All gas has some water in it, and in cars  that sit for long periods, they 
can rust from the inside out.