I posted earlier stating that after flushing my heater core I started getting coolant running into my floorboards. I know the heater core needs replacing but I thought I'd try some stop leak since this is my daily driver and needed a quick fix. It appears to have completely stopped the coolant leak. How much faith should I have in stop leak?

 

Stop leak works great but only bad thing about it is you are only supposed to use it when you need a quick fix(emergency) After a little bit it starts to clog up the heater core and rad and before you know it you are overheating and having no heat. We once used it in our 95 jeep grand cherokee and it had to be flushed 8 times before all the stuff was out of it.

 

It's better to not use any kind of stop leak, but I believe the Alumaseal stuff is the lesser of the evils'. At least the Alumaseal will help conduct heat, where as the other goo's will decrease the rad's ability to transfer heat.

I put Alumaseal in the Dak radiator about 5 years ago because the lot I bought it off of smashed the power steering pump into the rad and created a pinhole leak. Knock on wood, it has never leaked a drop since and I have never been able to cause it to overheat (Even here in Phoenix when it gets to 118 deg outside) and as far as I can tell, the Alumaseal has not caused any problems. Who knows, it might increase the wear on the water pump or something but I have had no issues. I will probably sell the Dak soon, so the $5 for the Alumaseal was much cheaper than replacing the Radiator.

 

I don't put stop leak in anything.I prefer it to be done right and I have heard too many stories about it stopping stuff up and doing more harm than good.That's just me though.

 

I used that stuff in an old truck with a bad head gasket. After rebuilding the top-end once before and not going that route again, I used that stuff to get by until I could get a new engine. It worked well for a while, a few thousand miles maybe, but then it gave out. And when that stuff stops working, it gives out all at once, so in the case of a head gasket or major coolant leak, don't take it very far from home.