Has anyone noticed any o-ring swelling after using Bar's Leaks? I put a bottle of Bar's Leaks Stop Leak in my mother's Sunfire GT 2.4L a few months ago to seal a small leak in a water pump housing gasket that would have required a lot of unpleasant work to replace, and it may have caused some o-rings to swell.
The car began leaking coolant heavily a couple of weeks ago and I determined that the problem was a broken water outlet - a plastic piece that splits flow from the engine to the radiator and heater core. It has an undersized pipe end (hidden under flange in linked picture) that fits into a larger hole in the block, and is sealed by an o-ring fitted on a groove in the plastic outlet. The outlet broke at the groove, and the o-ring is now so large in diameter that it's hard to imagine it could have ever fit tightly. The o-ring on the pressure cap is also much larger than it used to be and no longer fits snugly in its groove. I'll be replacing the pressure cap along with the outlet.
I wonder if the swelling caused the plastic to break? All the parts shops I called had it in stock, so it's a very common replacement item. That seems unusual to me considering that it would likely never wear out. So maybe they just break regularly and it was all a coincidence. Or maybe they fail whenever someone adds a product that swells o-rings. The only reference I could find to Bar's Leak seal swelling is a post on another forum from a poster called puzz1ed, near the bottom of this page:
Disappearing Coolant
There are many positive comments from Bar's users on this site and this particular problem - if it's even caused by Bar's - is unique to this vehicle. But I don't think I'll be using this sort of product again. In hindsight, a day spent swearing at that car wouldn't have been so bad if it fixed the problem properly without side effects!
The car began leaking coolant heavily a couple of weeks ago and I determined that the problem was a broken water outlet - a plastic piece that splits flow from the engine to the radiator and heater core. It has an undersized pipe end (hidden under flange in linked picture) that fits into a larger hole in the block, and is sealed by an o-ring fitted on a groove in the plastic outlet. The outlet broke at the groove, and the o-ring is now so large in diameter that it's hard to imagine it could have ever fit tightly. The o-ring on the pressure cap is also much larger than it used to be and no longer fits snugly in its groove. I'll be replacing the pressure cap along with the outlet.
I wonder if the swelling caused the plastic to break? All the parts shops I called had it in stock, so it's a very common replacement item. That seems unusual to me considering that it would likely never wear out. So maybe they just break regularly and it was all a coincidence. Or maybe they fail whenever someone adds a product that swells o-rings. The only reference I could find to Bar's Leak seal swelling is a post on another forum from a poster called puzz1ed, near the bottom of this page:
Disappearing Coolant
There are many positive comments from Bar's users on this site and this particular problem - if it's even caused by Bar's - is unique to this vehicle. But I don't think I'll be using this sort of product again. In hindsight, a day spent swearing at that car wouldn't have been so bad if it fixed the problem properly without side effects!