sealing a cracked block

D

Dale2

Member

• Dec 5, 2023

• #1

Does anyone remember a product that was called liquid glass from the 1970s. We would get it at the drug store, it looked like thick water and we would put it in the radiator to seal a cracked block. I am trying to remember the actual name of it. Hope someone can help me.
Thanks
Dale

 

R

rrlund

Well-known Member

• Dec 5, 2023

• #2

.
Water glass

 

MarkB_MI

Well-known Member

Location

Motown USA

• Dec 5, 2023

• #3

Even back then there were better products than sodium silicate. Folks I know who've used K&W Block Seal swear by it.

 

L

Leroy

Well-known Member

• Dec 5, 2023

• #4

Yes water glass, we used in in the can milk cooler for a water leak. Would have been in 79 or 79. I don't think it is avaible any more for years.

 

O

old

Well-known Member

Location

Camdenton Missouri

• Dec 5, 2023

• #5

Ive had good luck with Bars leak copper and things I have used it in have held up for years after I put it in

 

D

dr sportster

Well-known Member

• Dec 5, 2023

• #6

Moroso ceramic engine sealer

 

T

the tractor vet

Well-known Member

• Dec 5, 2023

• #7

Two products K and R block sealer or and Iron Tight block sealer . With both the block must be chemically cleaned and flushed , then they are filled with water and warmed up to around 200 degrees and allowed to run for something like 20min. at that temp. Then shut down and the block totally drained and allowed to set for 24 hours . These are commercial grade and work vary well . NOW if you have a area that has compression then this is a different ball game , a compression leak can be sealed BUT it takes a different route to do so.

 

Hemmjo

Member

• Dec 5, 2023

• #8

You don't want to get sodium silicate (water glass) in the wrong place in your engines. That is what they used during the Cash For Clunkers program to disable engines so they could never be rebuilt. Drain the oil, pour on a 1/2 gallon of it, start the engine, did not last long.

 

OP

OP

D

Dale2

Member

• Dec 5, 2023

• #9

Thanks to everyone for all the info

 

stevieb49829

Well-known Member

Location

Spirit Lake, Idaho

• Dec 5, 2023

• #10

Dale, if you are looking to seal a crack in a block, I cleaned the 2'' crack really well, using a tooth brush and lacquer thinner. I V'd it out just a little bit, and squished JB Weld into the prepped crack, sort of like packing a wheel bearing. Not a hint of a leak in over 2 years, and after paint, you couldn't tell it was repaired. I've heard you could also apply a vacuum to the water jacket and have the vacuum pull the epoxy into the crack. I didn't need to do that. stevee

 

S

Stephen Newell

Well-known Member

• Dec 5, 2023

• #11

Anything that would seal the block would plug the radiator as well.

 

J

John Garner

Member

• Dec 5, 2023

• #12

It's generally a good idea to stop-drill the ends of cast iron cracks.

 

D

Dean

Well-known Member

• Dec 5, 2023

• #13

Probably speaking of what was often called water glass, I.E., sodium silicate.

I recommend K & W Block Seal. Follow the directions precisely.

 

J

John-MI

Member

• Dec 6, 2023

• #14

My dad had a car lot way back. Early 50s. He always had a few bottles on hand. Called it egg preservative. I caught hel one day when I opened the bottles up and they immediately turned to glass when the air hit them.

 

K

KL in Wi

Member

• Dec 6, 2023

• #15

There are radiator-block sealers that have sodium silicate in them. Just saw one a few weeks ago at NAPA

 

T

Texasmark

Well-known Member

• Dec 6, 2023

• #16

I bought a half submerged Starcraft with a 110 hp 4 cyl. I/O. There was about a 2 horizontal crack in the middle of the block, at the bottom of the water jacket portion of he block. As others have said I did the prep, applied a abundant coat of JB Weld and it lasted the 10ish years the family had the boat.

 

R

Russ from MN

Well-known Member

Location

Bemidji MN

• Dec 6, 2023

• #17

I always had good luck with Bar's stop leak.

 

M

Mark-Ia

Well-known Member

• Dec 6, 2023

• #18

Walmart used to have it

 

Crazy Horse

Well-known Member

• Dec 6, 2023

• #19

Interesting experience John ..... I wonder how your dad was going to solve that problem had he opened them up?