GM Cooling System Seal Tabs

[rc1626]

Just recently did head gaskets and thought of using these as a "just in case" to possible leaks. For those that have used them before, how many of the tabs are you supposed to use? They come in a pack of six and the directions are not very clear. Directions state, "Empty entire contents of supplement into full radiator. (Pellets may require crushing)." So does this mean all six or just one? If it is truely evident of how many and I'm just not seeing it, I'm very sorry. Any help would be greatly appreciated. Thanks in advance.
Rob

 

[Turbo Brian]

Nothing scientific, just my experience. The sealant tabs work pretty good. Assuming that you have fresh head gaskets, I would use just 2.

On one family car, a head gasket was starting to pump exhaust gases into the cooling system and I used all 6. It seemed to stop the leak but the car also seemed to run consistantly hotter (about 20 degrees) even with a new thermostat. I think that the sealant tabs also sealed up the radiator a bit.

The tabs are shaped to easily fit right into the radiator filler neck, pretty cool product.