Is there a best/preferred brand for a radiator drain?

[Andrew Trout]

The radiator drain on my 1961 Cadillac won't close. It has a slow drip that become a rapid stream when the engine is running despite my best efforts to tighten/close it.

Is there a recommended brand for replacement?

[Daryl Chesterman]

I don't know what your radiator currently has on it, but I put one like the following link shows, on my 1959.  This allows for putting a hose on the outlet to direct the radiator drainage into a container without making a mess.

     https://hi-line.com/1-4-mpt-angle-bib-drain-style-1-drain-cock/

I can't remember if it is 1/4" or 1/8" male pipe thread—I'm thinking 1/4".  If this is the style that you would like to use, you can go to your local NAPA and ask them for part # 120 for the 1/4", or part # 150 for the 1/8".
If you are uncertain, take the old one with you so the counter person can match the thread size.

Daryl Chesterman

[Clewisiii]

1961 Radiator drain

[Andrew Trout]

Thank you!

When installing, do you put Teflon tape on the threads of the drain?

[Cadman-iac]

Thank you!

When installing, do you put Teflon tape on the threads of the drain?

 You can use Teflon tape or a pipe sealer, just something to help seal the threads. The Teflon tape is the cleanest and easiest to use.
 Rick

[fishnjim]

Sounds like time for a radiator flush and new coolant, too.
At least add some corrosion inhibitor, if reusing the old. 
Most of these are coming from off shore now and always was a replaceable part, not expected to last forever.

[Andrew Trout]

I can't remember if it is 1/4" or 1/8" male pipe thread—I'm thinking 1/4".  If this is the style that you would like to use, you can go to your local NAPA and ask them for part # 120 for the 1/4", or part # 150 for the 1/8".
If you are uncertain, take the old one with you so the counter person can match the thread size.

Daryl Chesterman

The 1/4" drain worked. Ordering from NAPA was an unexpected adventure. I went to the large regional hub to get the part, but they don't stock it. It's carried in the even larger hub in Buffalo. Over 10,000 SF of space and they can't find room for some radiator drains. 

Sounds like time for a radiator flush and new coolant, too.
At least add some corrosion inhibitor, if reusing the old. 
Most of these are coming from off shore now and always was a replaceable part, not expected to last forever.

Thanks for the suggestion, it's a good thing to keep in mind. I run Evans Waterless coolant in my car, so there's no water in the system for corrosion. I did put in new coolant as Evans Waterless coolant is hygroscopic and it's been damp & raining the past week. I'll need to replenish my on-hand supply.

A silver lining to this is when I go to the local waste disposal to get rid of the old coolant I can dispose of some other hazardous household wastes the previous owners left behind in the garage.

[Cadman-iac]

The reason why they don't stock that part anymore is because it's not been used on  newer cars with the plastic and aluminum radiators, and if it doesn't move, it doesn't get stocked. An unfortunate result of today's economy.
 You might have had better luck looking for one at an Ace Hardware store. But I'm glad you found one.

 Rick

[Varooom]

I just picked up one without the nice little drain at AutoZone.  It's a Dorman 1/4" brass drain cock.  They look at you funny if you ask if they have a pet cock these days. 

They had them hanging on a little rack.  Amazon has them too but pricey.