Originally Posted by bars leak website

THE TRUE STORY OF HOW BAR’S LEAKS SAVED THE USS NAUTILUS.

Bar's Leaks Yesterday:

In an automotive radiator a tiny leak might not mean disaster: But on a U.S. nuclear submarine during a top-secret mission under the Arctic ice cap, a tiny salt-water leak would have proven deadly for the sailors aboard the USS Nautilus were it not for the amazing stop leak capability of Bar’s Leaks.

Here is their true story:

En route to the polar ice cap, the engineering crew discovered that a small salt-water leak had developed on one of the nuclear reactor steam condensers. The leak was spilling sea water onto a critical piece of machinery, causing noxious fumes to fill the Engine and Maneuvering Rooms. A submarine is a labyrinth of tubes and pipes, so pinpointing the leak while at sea would have been impossible. Something had to be done.

In Seattle, the sub’s last port before embarking north, the commander had an idea to save the mission: He sent his men out to buy as much Bar’s Leaks as they could find. Dressed in civilian clothes, the crew covertly spread out over Seattle to purchase the legendary stop-leak solution.
With the Bar’s Leaks safely on board, sailors poured 70 quarts of it into the submarine’s condenser system.

It worked!

With the leak stopped, the USS Nautilus was able to complete its top-secret mission, becoming the first submarine to cross the North Pole underneath the Arctic ice cap.

Originally Posted by dhvaughan

it depends on how big the crack is. stop leak products work well on small leaks, by building up a hard crust when exposed to air. don't pay any attention to everyone's doom and gloom comments that stop leaks are terrible, and they stop up the heater core, and stop up the radiator, blah, blah. when in solution they do not harm. when oozing out of a leak, they crust up.

give it a try and report back.

but - what's important is - where is this crack and how big is it ?

edit - other products that can work, depending on getting a clean surface, are JB Weld, and a huge glob of RTV.

Originally Posted by UnregisteredUser

I've got lots and lots of experience with Bar's Leaks. Ya see, my father is a hillbilly. He's so bad about it that other hillbillies put him down for his mickey mouse fixes. He loves Bar's Leaks. He's probably drunk a couple bottles of the stuff when he was good and drunk and didn't want to get out of the chair in the garage to go pee.

I would NEVER use that stuff on a block or radiator or heater core that I wanted to keep. NEVER. It tends to plug up the lower reaches of the water jacket, and can lead to overheating problems -- not big boil over problems, but engines that run a tad hotter than they ought to, which decreases their lifespans.

That said, the lifespan of your engine ended already and you need a new block anyway, so go for it. Can't hurt much, might help a lot. Hey, you're making the big bucks now, right?

I'd pour it in without a second thought.

Originally Posted by UnregisteredUser

I've got lots and lots of experience with Bar's Leaks. Ya see, my father is a hillbilly. He's so bad about it that other hillbillies put him down for his mickey mouse fixes. He loves Bar's Leaks. He's probably drunk a couple bottles of the stuff when he was good and drunk and didn't want to get out of the chair in the garage to go pee.