1973 1/2 911 T Fuel Tank Problem

[gbanz]

I have dirty gas (fuel is discolored, dark gray with black particles) in the gas tank. What is the procedure to remove the tank and what is the best way to clean the inside of the tank?

1973 1/2 911 T (CIS injection)

Thanks for your help.

[Jim Sims]

Run the fuel level down. Disconnect the battery. Drain tank from bottom; there's the filter screen plug labeled "Benzin" and one other drain plug. One can make a tool out of a metric bolt to fit the bigger inside hex of the filter screen plug. Disconnect the lower fuel lines. Remove or fold back the front trunk felt and remove spare wheel/tire and tools. Disconnect the rubber hose to the filler neck and the vent hose on top. Unplug the fuel level sender harness. Remove the three vinyl covered clips on the top edges of tank. Lift tank out of car. Be prepared to replace the foam rubber sealing gasket that is between the tank edge seam and the chassis. Also be prepared to find corrosion in this area. On the tank seam, clean up with a power wire brush, apply anti-rust paint like "Corroless" and if you desire recoat with the grey "rocker schultz" OEM coating available from Wurth USA. Appling this coating takes a special spray gun which Wurth also sells. The 73.5 T with CIS tanks have internal plastic baffles. These baffles will soften/dissolve if subjected to the standard tank cleaning/internal sealing chemcials/methods which can involve various acids and acetone. I would find a tank cleaning/sealing shop that can handle a tank with internal plastic parts or merely remove the tank and rinse, slosh and drain several times with gasoline. Good luck, Jim

[pwd72s]

I hope you're on broadband. I tried to do a search (click on search icon) but it loaded so slowly I gave up. Anyway, there have been excellent threads here on your problem. The gas tank drops out from underneath. You need to drain it completely before removing it. There are services (mentioned in the threads I can't bring up) that can re-coat the inside of your tank after cleaning. There are also new replacement tanks available through aftermarket sources. I'm not trying to be nasty here, but do the search...it'll give you the info you're looking for.

[Jim Sims]

pwd72s, Sorry, but in 73.5's at least, the gas tank lifts upward out of the car. I am all too familar with this operation having done it a couple of months ago. It was very messy! Cheers, Jim

[Jim Sims]

Also remove fuel level sender (you'll need a new gasket when you reinstall it) and filter screen plug before cleaning tank. Jim

[Sunroof]

I am tackling the same problem with my 73.5 T. I purchased a repo tank from PAP in Georgia, but have yet to install it. Since I have had the car just about 100% restored, I feel a new tank may is in order. In the interim, and as a precautionary basis before I install it this winter, I change my fuel filter every 3-4K and never let the gas level get down below the 1/2 mark. That seems to do the job well. Thats only a bandaid though to remedy the source problem. That "river bottom" black sediment is your tank rusting all right!! I have read several threads about POR 15 for the home application to just having it done by a radiator shop. Which is the wiser move since they are experienced. This latest about "plastic baffles" is disturbing. From what I have read, the removal and replacement of the tank is not tough, just be very careful when disconecting and replacing lines on those plastic fittings and VENTILATE, VENTILATE, VENTILATE.

Also...........do yourself a favor and go to your local ACE or Home Depot and buy a long strip of that self adhesive foam gasket that goes under the tank for moisture proofing. The dealer wanted $30.00!!!!!!!!!!!

Concensus is to just replace that filter that screws into the bottom of your tank. Might as well replace it since its accessible and old.

Regards
Bob
73.5T

[Jim Sims]

Do not drain gasoline and remove the gas tank while the car is in a home garage. Many garages have a hot water heater and or clothes dryer with flame source which can ignite the gasoline fumes. Do this task outside where there is plenty of ventilation and have a gasoline/oil fire rated fire extinguisher on hand. Jim

[joehahn]

...POR15 is simple, I'd do that. One other thing....be careful where you put tank down when you get it out. Mine had undercoating black gooey crap-ol-a on it and it got on me, clothes, etc. Worst part was when I put tank in sun to dry I plopped it on wooden deck/bench, there still is undercoating there almost one year later.

Joe 68 L (in the shop right now...may come back non-sporto)