It’s understandable that we ALL want to save a buck if we can. Not all of us are “Do It Yourselfers”, but for the ones that are, here’s a heads up. There are many “stop leak” products in your local auto parts stores. The problem is 99% of the time they don’t work & cause more damage than if the leak was untouched.
A/C Systems;
OK, your Subaru’s A/C system isn’t cooling like it used to, so you go down & by the kit to recharge/ refill it. The majority of the time this kit has a type of stop leak in it. Understandable, the Freon went somewhere didn’t it. You want to stop the leak & refill the system all at once. Great idea until it turns out it either doesn’t work or doesn’t work for long. NOW…you bring it in for a “proper” repair & find out that it costs you an additional $200.00-$400.00 just to flush the system before we can recharge the system and access what else this stop leak might have plugged up. We have seen these “stop leak” products take a common O-ring replacement & a recharge, normally less than a $200.00 job, into well over a $1,000.00 repair.
Engine cooling systems
If you put in a “stop leak” product to stop &/ or fix a coolant leak or put off a head gasket repair, you may have just cost yourself an engine. The product is made to “plug” a leak right? But you have to ask yourself “What else am I plugging up?” The heater core, the radiator, and, the most costly, the passages inside the engine. We’ve disassembled more than one Subaru engine that had a type of crust that formed inside these passages that didn’t allow the coolant to circulate causing the engine to run even hotter. Wasn’t this the problem you were trying to solve?