GM has dropped a bars pellet in the cooling system of every car built. To this day if you have a leak under warranty the first thing they do is use bars. They even have a GM part number for it! I had a head gasket on a 4 cyl S-10 that blew and it was in the winter so I used Bars to get me to the summer......8 years later,never got to it and it still did not leak.

 

X2^ Not another brand, Just AlumaSeal. The small tube is about the diameter of a quarter, and you can start by using just 1/2 of it. At least three times I've stopped a small leak in a heater core with it with no noticeable problems. It's a fine powder that will just keep circulating around in there. I've seen fine sparkles in my coolant a year after adding it!


It can settle in a low flow area. As I kid I once got carried away with it. When I pulled the head on that Rambler, I found 1/2 an inch of it settled back behind #6 cylinder! (Less is better here)

This one might be a candidate for Sodium Silicate?

 

Yea head was cracked. Moral of the story is stop leak fixed it. Is it a band aid sure. Does it quite often work for a very long time, yea.

 

The "buy here - pay here" used car lots use black pepper.

 

When I sold auto parts in college, we referred to this as a "mechanic in a bottle."

People would pour all types of crap into their cooling systems... Crank cases... ect...

I do believe that there is no real replacement for hard parts...

But we did sell a product (referred to in a previous post) called Blue Devil. For those who could afford it, I never had anyone come back and give me a bad story about it or want their money back.

Some installer customers swore by it.

I would never use any pour in treatments in my vehicles, just personal preference. But just sharing from experience.

 

2x on it being head vs block

 

Chuck, somebody....would Sodium Silicate work on an external crack in the block? (might be it needs combustion temps to turn to glass)
Not that the spendy new carbon fiber treatments might not have some merit, but 1/2 of a $1 tube of AlumaSeal might just plug that up. It's just powder. Something to try that's maybe better than pepper. (nothing against pepper!)

OK>
"Liquid glass" (sodium silicate) is added to the system through the radiator, and allowed to circulate. Sodium silicate is suspended in the coolant until it reaches the cylinder head. At 100–105 °C sodium silicate loses water molecules to form a glass seal with a re-melt temperature above 810 °C.
A sodium silicate repair will last two years, sometimes longer. The repair occurs rapidly, and symptoms disappear instantly. This repair only works when the sodium silicate reaches its "conversion" temperature at 100–105 °C. Contamination of engine oil is a serious possibility in situations in which a coolant-to-oil leak is present. Sodium silicate (glass particulate) contamination of lubricants is detrimental to their function.


So it needs to be hotter than boiling. Was thought, see more> http://en.wikipedia.org/wiki/Sodium_silicate

 

"Edit" is botching up for me. I meant "was a thought"

 

"Contamination of engine oil is a serious possibility in situations in which a coolant-to-oil leak is present. Sodium silicate (glass particulate) contamination of lubricants is detrimental to their function".


I have seen engines seize up after using silicate crack repair kits. That is the same stuff they used on "cash-for-clunkers" to permanently destroy engines! For an external leak it has been known to work. Internal leak like a 0331 head is a big NO-NO. The 0331 head crack changes in dimension as engine temperature changes so NO rigid sealant (like water glass) will ever hold.

 

His first post made me wonder if it might be a thought. I guess when it works, it works great....myself I'd probably try the AlumaSeal.

 

If its a straight line I might even try widening it up and packing it with JB Weld. Not on the combustion side so don't even need the high-temp stuff.

 

Interesting thought. An old trick is to drill a hole right at the end of a crack to stop it from growing. And agreed, just putting glue over a crack is about pointless, but "hogged out" so it can get in there it might have a chance. Booger though that epoxy's seem to fair better with oil than they do with water, (in my experience). I've seen JB weld soften, at least once.

I had some success on an old beater repairing rad. tubes. I opened up the crack, mixed just regular clear epoxy with fiberglass insulation and jammed it in there and it held.

 

I have seen a number of tractor with cracked blocks that were successfully brazed. Seen one that was stitch welded with cast iron arc rods.

 

Yep. Anything you pack in from the outside will eventually blow back out.
The metal will expand and contract while the cooling system pressure is pushing outward. Alumaseal OTOH will be forced into the crack until no more fits and should stay there.

 

It's an open forum, so even a dummie like me gets to speak! Yea, if that area could be heated enough to brase...(with the end of the cracks drilled) Way beyond my experience, but I like it.

Radi constantly seems to "know things" No comment Chuck, on the sodium silicate?