Help! Fuel tank has a pin hole leak

[78 Shark]

Hello all,
I pulled my fuel tank on my 78 as I am restoring the frame. The tank had a little fuel left in it and as I turned it to clean it I found a little wet spot on the side of the tank. I was going to purchase a tank sealer from Eastwood or KBS coatings but as I pulled the sending unit out to look inside, the tank is plastic inside. The coatings are not guaranteed to work with plastic. What are my options other than buying a replacement tank.
Thanks, 78 Shark

 

[White75]

Mighty Putty


In all seriousness. Try to find someone that can fix them or buy a new one.

 

[mkapp7879]

I had a pinhole in one of my 78s fuel tanks too. For a few years all the leak amounted to was a reddish/brown spot on the bottom of the tank. Last year I noticed a stain on the spare tire lid which prompted me to drop the tank. This was a LOW, LOW mile Vette, too.
Started pokeing around the area of the pinhole and ended up with several more. Tried the epoxy fix some people suggested. Three months later dropped the tank again. The patch was blistering and oozed when I scraped them.
New tank!
Got mine from an ebay seller, $225 buy it now plus $25 shipping(plus I had a 10% off coupon from PayPal!). Cheapest I could find it. It actually was drop shipped from Mid America so it's the same one the vendors sell. I'll look up the seller's name and post it.

'thepartsladi'

 

[78 Shark]

Hey mkapp7879, thanks for the reply. How did the sending unit bolt down in the new tank? I asked around and some said I have to use the existing bladder ring from my old tank to hold the sending unit in. Is this true for the one you bought?

 

[Hib Halverson]

You have no safe DIY options other than a new tank.

 

[mkapp7879]

Hey mkapp7879, thanks for the reply. How did the sending unit bolt down in the new tank? I asked around and some said I have to use the existing bladder ring from my old tank to hold the sending unit in. Is this true for the one you bought?

The replacement tank is made without the plastic liner and I pretty much decided not to worry about it. Older C3s don't have a liner, and none of my other past cars had liners. It's more of an impact safety thing.
The new tank had a welded in flange for bolting the sending unit in. No need to salvage anything from the old tank.
I do believe the mid year C3s with the RUBBER bladder needed to keep the rubber ring from the bladder but not on our years.
Oh, and the tank arrived at my home in 2 days! But I am in Illinois as is Mid America.

 

[78 Shark]

Thanks

Thanks for the info. Some of the vendors, when purchasing a new tank require the old bladder ring to be cut out and reused to hold the sending unit down. I will purchase the one from thepartslady on ebay. Thanks again 78 Shark