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Bill Marcy
11-20-2014, 08:14 PM
We will be waking up the 1968 Superior, after an eight year slumber in a heated garage. I guess that dropping the gas tank is a priority. But, what would be the best way of having it cleaned? Has anyone done it themselves? If so, what do you use? In the event that it needs replacing, is a tank from a 1968 Pontiac wagon the same? Any help will be greatly appreciated. Thank you!

Doug Lemon
11-20-2014, 08:52 PM
Right or wrong,,this is what I did for my 1954 Cadillac sedan.
I dropped the tank. Took the sending unit out.
I then filled it with chains and nuts and bolts and rough gravel.
I then took a few days and shook that tank as best I could. Left right up down for as long as I could and as vigorously as I could. I did do a few rinses along the way. After I was satisfied that it was clean I emptied it and washed it with the garden hose. Remember now you have 2 good sized openings and one small opening (the outlet) that you can apply the hose to.
After all of that I sat it in the hot sun to make it sure it was good and dry.
I then applied a sealer (red) to the tank.

http://www.ftrs.com.au/redkote/red_kote.php

That was a few years ago,I still have the car and I have had no problems.

Daniel Scully
11-20-2014, 09:10 PM
Might call around to some local radiator shops,at least here there are a few that will boil out a gas tank.

Mike McDonald
11-20-2014, 10:05 PM
Bill: We routinely drop and send gas tanks out to our local radiator shop to be boiled out on anything we buy that has been sitting for any length of time. To us, it's not worth the risk of having trouble later on. Often we do the same with carbs thru another local vendor who specializes in rebuilding old ones. You gave a beautiful car... Good Luck! MM

Doug Lemon
11-20-2014, 10:10 PM
Would boiling it out get rid of the rust and scale that could be inside the tank?

Bruce Biancalana
11-20-2014, 10:26 PM
You have to be careful and make sure that the galvanizing is not gone when the inside has been cleaned out. If rust is the problem and an abrasive or a corrosive chemical is used the galvanizing will be definitely removed. If this is the case the inside of the tank should be coated with a special coating used for gas tanks so as to seal the metal so the fresh bare metal tank does not start to re rust after the tank has been reinstalled. There are various products on the market for sealing the inside of a bare metal tank, check with the radiator shop and they can direct you if this is the case.

Mike McDonald
11-20-2014, 10:39 PM
You have to be careful and make sure that the galvanizing is not gone when the inside has been cleaned out. If rust is the problem and an abrasive or a corrosive chemical is used the galvanizing will be definitely removed. If this is the case the inside of the tank should be coated with a special coating used for gas tanks so as to seal the metal so the fresh bare metal tank does not start to re rust after the tank has been reinstalled. There are various products on the market for sealing the inside of a bare metal tank, check with the radiator shop and they can direct you if this is the case.

I forgot to mention that we have them coated as well as Bruce suggested. MM

John ED Renstrom
11-21-2014, 12:44 AM
everyone has there favorite way to wake up a old car. if there is a lot of gas in the tank I would drain it out. if it runs clear no rust, but smells bad drain it out put back in 5 gl of good gas. then check the fluid level in the engine and prime the car and see if she fires. you can create just a many problems as you are trying to prevent but doing two much to start out with. it was running when parked. if you don't play around to much with it it should run the same now.
you can figure on going thru the carb and maybe the fuel pump also but why before you know if the are bad or not. the worse that can happen is you suck some stuff out of the line or tank and it plugs the passages in the carburetor.
if it shows a lot of rust in the tank then get it running off a small tank up front.
disconnect the main line and put a gas hose on the suction side of the pump. see if it starts and runs that way. we ran the 58 here for 2 years on a 5 gal gas can in front of the radiator. don't great problems try to avoid them

Bill Marcy
11-21-2014, 08:30 AM
Thanks for all of the good information guys. Although everyone has a little different idea, they all lead in the same direction, getting it running.

Bruce Biancalana
11-21-2014, 09:39 AM
My experiences with varnished gas is not good. What can happen with just draining the gas down and putting in 5 gallons of fuel in and trying to run the motor, is that the varnished residual gas remaining in the tank can spoil the new 5 gallons of gas. I have had varnished gas actually coat the valve train and cause valves to stick and subsequently bend push rods. The problems usually don't show up until the motor is shut down and allowed to cool over night. The mixture of new gas and old varnish separates when the new fuel either ignites or evaporates leavening old sticky varnish to be distributed on the intake valves. As the contaminated gas dries and cools over night it becomes a sticky glue like substance. When the motor is re started the next day the valves stick, causing the push rods to be bent by the camshaft trying to open the stuck valves. I have had this happen many times.
When I resurrect cars that have been sitting, I always make sure that the tank is good and cleaned prior to starting a motor initially, thus avoiding any varnish to be run through the motor. While the tank is out or disconnected you can utilize an external gas tank hooked up to the fuel pump. The external fuel supply will allow for clean fuel to be pumped in by the cars fuel distribution system. The carb, filter, fuel feed line will need to be checked cleaned or rebuilt prior to the initial start. These extra steps will help prevent valve train issues caused by short cutting the removal of bad gas.

Richard Vyse
11-21-2014, 10:55 AM
When I fired up the Lifeliner for the first time after sitting for years just blocks off Lake Erie in Ohio, all we did was drain the tank and add new gas.

http://www.youtube.com/watch?v=1sKF8Ot0gY0&list=UUOiikDuL9AlEN8CAPv79jbA

John ED Renstrom
11-21-2014, 11:22 AM
the key is sitting how long and how much gas. one of the products like seafoam with a proper mixture will help clean out settled residue. but one look at the gas coming out is all you usually need to decide if it has turned to varnish. and you need to do a tank clean out first. if every joint you look at in the gas line ha a thick layer of gooey tart like stuff on it things have turned. the nice part about this new gas we get is you don't have to worry about varnish. the phase separation will take place in 30 days and the etoh and water combination will eat right threw the bottom draining the gas out long before it turns to varnish.

Bill Marcy
11-22-2014, 05:51 PM
My experiences with varnished gas is not good. What can happen with just draining the gas down and putting in 5 gallons of fuel in and trying to run the motor, is that the varnished residual gas remaining in the tank can spoil the new 5 gallons of gas. I have had varnished gas actually coat the valve train and cause valves to stick and subsequently bend push rods. The problems usually don't show up until the motor is shut down and allowed to cool over night. The mixture of new gas and old varnish separates when the new fuel either ignites or evaporates leavening old sticky varnish to be distributed on the intake valves. As the contaminated gas dries and cools over night it becomes a sticky glue like substance. When the motor is re started the next day the valves stick, causing the push rods to be bent by the camshaft trying to open the stuck valves. I have had this happen many times.
When I resurrect cars that have been sitting, I always make sure that the tank is good and cleaned prior to starting a motor initially, thus avoiding any varnish to be run through the motor. While the tank is out or disconnected you can utilize an external gas tank hooked up to the fuel pump. The external fuel supply will allow for clean fuel to be pumped in by the cars fuel distribution system. The carb, filter, fuel feed line will need to be checked cleaned or rebuilt prior to the initial start. These extra steps will help prevent valve train issues caused by short cutting the removal of bad gas.

Thanks for reminding me, Bruce. I had this scenario happen in a '68 Cadillac that had been sitting for about 18 months. The gas had turned and we damn near killed a strong running 472! The result was a top-end rebuild.

Paul Steinberg
11-22-2014, 10:26 PM
My 1969 Miller Meteor sat for over 10 years, and all that was done was to fill it with fresh gas, a new battery, and fire it up. It started and ran enough to get it onto the truck to bring it East. Everyone's experiences are different, and what works for one, might not work for another. It also might have to do with the regional differences in the make up of the gasoline. I have seen what Bruce has described, but I have been lucky enough not to have experienced it. It depends on how much work you can do yourself, and if you are a gambler. If you are a gambler, then don't drain, flush, and refill. If you are not a gambler, then follow Bruce's advise and you will be $$$ ahead in the long run..