Originally Posted by kparrent
Danthurs, you're opposed to even some of the lighter duty stop leak? I was looking into Bar'* as I hadn't heard much negative about it.
I used a stop-leak in my radiator, and while it didn't seem to gum up anything, my radiator developed a worse leak in a different spot less than two months later. Look at it this way: if you've got a gunshot wound, you can either buy a box of Band-Aids and patch the symptoms, or go to the hospital and cure the root cause.
In my case, the plastic tanks on the left and right sides of the radiator cracked. The typical tank crack will result in a slow, slooww, ssslllooooowww leak. At best, coolant will gently dribble down the side of the tank. On mine, it looked like the radiator cap was leaking, until I took a close look and saw the source about a half-inch below there.
My advice is, if you find a cracked tank, grab another radiator from the junkyard and swap them. It'* actually a pretty easy self-repair. All you need are hand tools and a two-gallon bucket.
There are also aftermarket all-aluminum radiators*which are immune to cracking tanks and are X% to Y% more efficient at transferring heat, but they're three to four times more expensive than a used OEM part.