My radiator drain plug had been leaking for a little while. Yesterday, I put on a new one. It has a new seal too (I tried to use the old seal, but it kept leaking). The question I had was how tight should the drain plug be? It seemed like it would get tight, and then with more turns, it would get loose again.

sounds liek you're twisitng it past it'* intened threading, its a plastic plug so if you keep doing that it will wear out the new plug, just get it acceptably tight, make sur eit isnt leaking, then check it in a few days to make sure it hasnt loosened or leaked

That'* what I planned to do. It'* not leaking so far. It'* just that I never got that comfortable feel that I'd like to get (to me a good tight is better than acceptably tight). But, I guess I will monitor closely.

Thanks.

Just snug it tight.....it is plastic afterall/....

Low coolant light came back on again last night, and there is still coolant leaking from that area. So, I guess I need more clarity on how exactly to do this. Is it hand tight only?

Get it as tight as you can with your hand. Then, I like to take a set of pliers to it and twist it no more than 1/8 - 1/4 turn just to make sure it'* snug. Never had an issue.

You might have stripped the threads in the radiator and not the actual plug. If that'* the case try chasing the threads.

What does chasing the threads mean?

I took off the drain plug again, and put it back on (hand tight plus 1/4 of a turn). The seal was fine. I also shoved a wooden dowel in the drain tube in case the threads for the drain plug in the radiator were damaged. I also put in Prestone Super Leak sealer and bled the system of air twice. Still leaking!

The coolant puddle is directly underneath the drain plug, but it is very difficult to see the actual plug (it is a very tight spot), so I can't say with 100% guarantee that it is, in fact, the plug.

What are my options, short of replacing the whole radiator? (how long a job is that anyway?)

My guess would be warm up the engine (to build pressure. Grab some rags, a mirror, and a flashlight and contort yourself as necessary to see the actual leak. Then work from there.

If it'* a small enough leak, some High Temp silicone may be your best buddy. Certainly cheaper than a new radiator. NOTE: The silicone deal would ONLY be good for a very slight leak!! If it'* more than a pin hole, solder it (if you can on our radiators) or replace it.

Your radiator might be cracked. It could be such a small crack that it only swells when hot.

I agree with MOS.... Warm it up and get under there with a mirror and flashlight. Don't add anymore "mechanic in a bottle". That stuff only reaks more havoc down the road.