Radiator drain & gas tank leak question

[norcalsvt]

Have a couple of questions. I replaced my radiator with one of the aluminum ones from ebay & I need to figure out what size the drain plug petcock is. I bought one but of course it didn't fit. I emailed the place I purchased it from but no response yet. I even tried to removed the one on the old radiator but it wouldn't come off.

Second question is a leak in the gas tank in the trunk. I never top off the gas, but decided to the other day & then i notice a little bit off gas in the trunk. I siphoned out 5 gallons & then looked for any obvious holes or rust & didn't find any. Not sure where it came up from. Wondering how safe it is drive? With the wet cold weather gas low enough in the tank from spilling into the trunk?

 

[zookeeper]

The drain petcock should be an NPT (tapered pipe thread) size. If you just want to put a pipe plug in, go to the hardware store and grab a couple different sizes and see what you can find. Make sure you use some teflon tape. Pipe threads are different thread pitches than standard bolts, which is likely why you couldn't fit whatever you were trying to thread in there. As far as the gas leak, please, please, please don't drive your car until you fix it. My old '65 fastback had a split hose that connects the filler to the tank and it leaked. I think they're less than $10 from NPD and it could save your life. Even if it turn out to be the tank as the source of your leak, they are cheaper than a day in the burn center or the current price of caskets. Gas leaks are never a place for "good enough".

 

[65ShelbyClone]

The difference with NPT threads is that they are tapered; that's why a regular bolt won't fit. The thread size on the radiator drain is very likely a 1/8-27 NPT. That's all I have ever seen in the all-metal radiators.

And yes, replace the filer neck hose on your gas tank. Now!

 

[norcalsvt]

thanks for the replys. I believe the fuel was coming up through the tank not from the hose. I will check the hose though. If thats all it is I can replace that no problem. If it's the tank then I will have to park it in the garage until the weather is nicer to remove the tank.

 

[65ShelbyClone]

Once you get the tank siphoned out(or drained it has a drain), it's not even a one-hour job to replace it. When you're ready to start inspecting the tank and filler neck, go ahead and get a new filler hose and cork gasket to go between the filler neck flange and body. You'll need to replace both whether the tank is bad or not.