I've heard good things about 'Blue Devil' from some of the local shops.
They say follow the directions exactly! (An endorsement from 3 local shops near me)
I'm sure that the life of it is probably dependent on the severity of the 'wound'.
I have a diagonal crack in my '46 Willys Jeep block. It's about 5 inches long and is perfectly centered up on a freeze plug. It was found after the block was machined back in 1995.
'The Crowd' demanded I get another block/ or drill the beginning and end of the crack to 'stop it'/ follow a pre-heating torch with a nickle welding rod. Otherwise I was screwing up!
I'm hard headed!
But mostly was 'Financially Challenged'
At the time, I had to just "go with it".
The machinist gave me 2 're-builder's blocks' (like 1 inch square x 2 inch long carbon/ charcoal like blocks) to stick in my radiator after it started seeping coolant.
This worked well for about 2 months then I noticed a little moisture on the crack. I added another block.
It's now 22 years later, the crack is still visible, NO MOISTURE at all crack has not grown!
Click on 4th pic below
So I reckon if you are not in love with this vehicle (As I am with my two Jeeps), If you get good results with the sealer, but fear a relapse, dump that puppy on Craig's List/ news paper/ Auto Trader/ in the yard with a sign on it while it is doing well!
Moral of the story
It's your call!
The Medic
Images (Click to make bigger)
Tuesday, April 11th, 2017 AT 5:56 PM