73.5 fuel tank

[RFM]

Group:
I have a pin hole leak in the "swirl pot" fuel tank in my '73.5 911T.
Does any one know if the sheet metal seam is soldered (couldn't find any pin spot welds)?
I want to split and restore the ORIGINAL tank, not retrofit a later year/version...have already considered that fix. It's a low mileage pristine example.
Thanks,
Reed

[Sunroof]

Reed,

Do a search on the 73.5T tank and you will see a lot of photos of the 73.5T tank split open showing the swirl pot and adjoining parts. The swirlpot is made of bakelite with the similar thickness of a distributor. How do you know its leaking since its constantly enveloped in gasoline? Perhaps its not your swirlpot but the tank itself. If you have a leak in the tank wall then other issues like internal rusting might be going on. Remove the fuel level unit and use a flashlight to look inside the tank. They will rust! Several have chimed in here on having the tank split, cleaned, coated and re-welded at a cost between $700 to $1000.
You mentioned you do not want to replace it with anything but the 1973.5T, but the only sacrifice with a newer CIS tank is not having the space for a full spare tire. After 1973.5T they use a tire saver spare.

DO NOT use "redkote" internal sealant if you decide to restore the tank by boiling and recoating as the redkote will eventually flake off the bakelite and impact that long internal filter screen and stop you cold on the road! Trust me, thats what happened to me before resolving the issue. I am not sure if the POR 15 tank restoration kits will have the same issues with adhering to the bakelite swirlpot over many years.

Porsche dealers do sell the 1973.5T tank so you might want to check out their prices if you plan on keeping it all original.

Any photos of the car?

Good luck

Bob
1973.5T

[porwolf]

Here are some links for fuel tank insides and repairs:

CIS Gas Tank

CIS Gas Tank

So, what is the best way to clean the inside of a gas tank?

Post Photos of your Old Fuel Tank Strainer

1973 911-T (CIS) Fuel Tank Exposed

1973.5T fuel tank

Good luck!

[porwolf]

Here is another link with an original solution to the CIS tank cleaning problem:

Cleaning a Fuel Tank without damaging Plastic Swirl Pot

[E Sully]

Unfortunately, a member of the Early S Registry near me just sold his spare 73.5 cis tank last week. You can use a later tank with a space saver spare.

[Robert Adams]

Last fall I spoke with Stoddard and they were considering making a 73.5. They make the early tank and they make the later tank. The person I spoke with suggested they were giving it serious consideration so if all of us 73.5 owners needing a tank register with them, maybe they'll make it?

[RFM]

Thanks for the information Robert. I will contact/write/email Stoddards to encourage them to fabricate a correct 73.5 tank.
I'm still curious,however, to hear from anyone on the forum that may have tried to separate the two halves of the tank at the flanged seam WITHOUT CUTTING it. If, indeed, the seam is soldered, it would, theoretically, be much easier to separate, restore/clean the tank's interior, coat, then re-solder it. Cutting it would require mig welding it back....mig heat would compromise/destroy coating. Soldering would be much "cooler". I just hate to experiment with a potentially good tank (restored) with only a pinhole leak.
Anyone out there with a "junk" tank?...73.5 or later I could dissect?
Thanks,
Reed

[Sunroof]

I called Stoddard a year ago to inquire about a 73.5T tank. All they did is refer me to the newer CIS tank for the tire saver spare. If Stoddard decides to fabricate a 73.5T replica tank I figure its going to be over $900 or higher, but they are aware of us 73.5T owners who are stuck with this rare addition.

Watch Ebay as once in a while you'll see a 73.5T tank show up.

good luck
Bob

[Robert Adams]

Don't know that I would tackle splitting a 73.5 tank myself, there are a couple posts on 73.5 tanks one particular post splits one so you can see what's there.

CIS Gas Tank

I know my skill level is deficient for sure so I plan to have mine resurrected by Moyer if Stoddard doesn't come out with the 73.5 in time for me to get my car on the road.

Moyer Fuel Tank Renu - antique gas tank repair restoration, classic car gas tanks GASTANK

I have some time so not panicking just yet.

[Targa73]

How much would you pay for a "junk" 73.5 tank to dissect?